Programs & Examples On #Properties file

A .properties file is either a simple text file or an XML file containing pairs of keys and values. Java and related technologies frequently use .properties files to store configuration information.

Spring .properties file: get element as an Array

If you need to pass the asterisk symbol, you have to wrap it with quotes.

In my case, I need to configure cors for websockets. So, I decided to put cors urls into application.yml. For prod env I'll use specific urls, but for dev it's ok to use just *.

In yml file I have:

websocket:
  cors: "*"

In Config class I have:

@Value("${websocket.cors}")
private String[] cors;

How to read an external properties file in Maven

This answer to a similar question describes how to extend the properties plugin so it can use a remote descriptor for the properties file. The descriptor is basically a jar artifact containing a properties file (the properties file is included under src/main/resources).

The descriptor is added as a dependency to the extended properties plugin so it is on the plugin's classpath. The plugin will search the classpath for the properties file, read the file''s contents into a Properties instance, and apply those properties to the project's configuration so they can be used elsewhere.

How to read values from properties file?

In configuration class

@Configuration
@PropertySource("classpath:/com/myco/app.properties")
public class AppConfig {
   @Autowired
   Environment env;

   @Bean
   public TestBean testBean() {
       TestBean testBean = new TestBean();
       testBean.setName(env.getProperty("testbean.name"));
       return testBean;
   }
}

Where to place and how to read configuration resource files in servlet based application?

Word of warning: if you put config files in your WEB-INF/classes folder, and your IDE, say Eclipse, does a clean/rebuild, it will nuke your conf files unless they were in the Java source directory. BalusC's great answer alludes to that in option 1 but I wanted to add emphasis.

I learned the hard way that if you "copy" a web project in Eclipse, it does a clean/rebuild from any source folders. In my case I had added a "linked source dir" from our POJO java library, it would compile to the WEB-INF/classes folder. Doing a clean/rebuild in that project (not the web app project) caused the same problem.

I thought about putting my confs in the POJO src folder, but these confs are all for 3rd party libs (like Quartz or URLRewrite) that are in the WEB-INF/lib folder, so that didn't make sense. I plan to test putting it in the web projects "src" folder when i get around to it, but that folder is currently empty and having conf files in it seems inelegant.

So I vote for putting conf files in WEB-INF/commonConfFolder/filename.properties, next to the classes folder, which is Balus option 2.

Loading a properties file from Java package

To add to Joachim Sauer's answer, if you ever need to do this in a static context, you can do something like the following:

static {
  Properties prop = new Properties();
  InputStream in = CurrentClassName.class.getResourceAsStream("foo.properties");
  prop.load(in);
  in.close()
}

(Exception handling elided, as before.)

adding comment in .properties files

Writing the properties file with multiple comments is not supported. Why ?

PropertyFile.java

public class PropertyFile extends Task {

    /* ========================================================================
     *
     * Instance variables.
     */

    // Use this to prepend a message to the properties file
    private String              comment;

    private Properties          properties;

The ant property file task is backed by a java.util.Properties class which stores comments using the store() method. Only one comment is taken from the task and that is passed on to the Properties class to save into the file.

The way to get around this is to write your own task that is backed by commons properties instead of java.util.Properties. The commons properties file is backed by a property layout which allows settings comments for individual keys in the properties file. Save the properties file with the save() method and modify the new task to accept multiple comments through <comment> elements.

How to access a value defined in the application.properties file in Spring Boot

@Value Spring annotation is used for injecting values into fields in Spring-manged beans, and it can be applied to the field or constructor/method parameter level.

Examples

  1. String value from the annotation to the field
    @Value("string value identifire in property file")
    private String stringValue;
  1. We can also use the @Value annotation to inject a Map property.

    First, we'll need to define the property in the {key: ‘value' } form in our properties file:

   valuesMap={key1: '1', key2: '2', key3: '3'}

Not that the values in the Map must be in single quotes.

Now inject this value from the property file as a Map:

   @Value("#{${valuesMap}}")
   private Map<String, Integer> valuesMap;

To get the value of a specific key

   @Value("#{${valuesMap}.key1}")
   private Integer valuesMapKey1;
  1. We can also use the @Value annotation to inject a List property.
   @Value("#{'${listOfValues}'.split(',')}")
   private List<String> valuesList;

The Definitive C Book Guide and List

Warning!

This is a list of random books of diverse quality. In the view of some people (with some justification), it is no longer a list of recommended books. Some of the listed books contain blatantly incorrect statements or teach wrong/harmful practices. People who are aware of such books can edit this answer to help improve it. See The C book list has gone haywire. What to do with it?, and also Deleted question audit 2018.

Reference (All Levels)

  • The C Programming Language (2nd Edition) - Brian W. Kernighan and Dennis M. Ritchie (1988). Still a good, short but complete introduction to C (C90, not C99 or later versions), written by the inventor of C. However, the language has changed and good C style has developed in the last 25 years, and there are parts of the book that show its age.

  • C: A Reference Manual (5th Edition) - Samuel P. Harbison and Guy R. Steele (2002). An excellent reference book on C, up to and including C99. It is not a tutorial, and probably unfit for beginners. It's great if you need to write a compiler for C, as the authors had to do when they started.

  • C Pocket Reference (O'Reilly) - Peter Prinz and Ulla Kirch-Prinz (2002).

  • The comp.lang.c FAQ - Steve Summit. Web site with answers to many questions about C.

  • Various versions of the C language standards can be found here. There is an online version of the draft C11 standard.

  • The new C standard - an annotated reference (Free PDF) - Derek M. Jones (2009). The "new standard" referred to is the old C99 standard rather than C11.

  • Rationale for C99 Standard.


Beginner

  • C In Easy Steps (5th Edition) - Mike McGrath (2018). It is a good book for learning and referencing C.

  • Effective C - Robert C Seacord (2020). A good introduction to modern C, including chapters on dynamic memory allocation, on program structure, and on debugging, testing and analysis. It has some pointers toward probable C2x features.

Intermediate

  • Modern C — Jens Gustedt (2017 1st Edn; 2020 2nd Edn). Covers C in 5 levels (encounter, acquaintance, cognition, experience, ambition) from beginning C to advanced C. It covers C11 and C17, including threads and atomic access, which few other books do. Not all compilers recognize these features in all environments.

  • C Interfaces and Implementations - David R. Hanson (1997). Provides information on how to define a boundary between an interface and implementation in C in a generic and reusable fashion. It also demonstrates this principle by applying it to the implementation of common mechanisms and data structures in C, such as lists, sets, exceptions, string manipulation, memory allocators, and more. Basically, Hanson took all the code he'd written as part of building Icon and lcc and pulled out the best bits in a form that other people could reuse for their own projects. It's a model of good C programming using modern design techniques (including Liskov's data abstraction), showing how to organize a big C project as a bunch of useful libraries.

  • The C Puzzle Book - Alan R. Feuer (1998)

  • The Standard C Library - P.J. Plauger (1992). It contains the complete source code to an implementation of the C89 standard library, along with extensive discussions about the design and why the code is designed as shown.

  • 21st Century C: C Tips from the New School - Ben Klemens (2012). In addition to the C language, the book explains gdb, valgrind, autotools, and git. The comments on style are found in the last part (Chapter 6 and beyond).

  • Algorithms in C - Robert Sedgewick (1997). Gives you a real grasp of implementing algorithms in C. Very lucid and clear; will probably make you want to throw away all of your other algorithms books and keep this one.

  • Extreme C: Push the limits of what C and you can do - Kamran Amini (2019). This book builds on your existing C knowledge to help you become a more expert C programmer. You will gain insights into algorithm design, functions, and structures, and understand both multi-threading and multi-processing in a POSIX environment.

Expert


Uncategorized

  • Essential C (Free PDF) - Nick Parlante (2003). Note that this describes the C90 language at several points (e.g., in discussing // comments and placement of variable declarations at arbitrary points in the code), so it should be treated with some caution.

  • C Programming FAQs: Frequently Asked Questions - Steve Summit (1995). This is the book of the web site listed earlier. It doesn't cover C99 or the later standards.

  • C in a Nutshell - Peter Prinz and Tony Crawford (2005). Excellent book if you need a reference for C99.

  • Functional C - Pieter Hartel and Henk Muller (1997). Teaches modern practices that are invaluable for low-level programming, with concurrency and modularity in mind.

  • The Practice of Programming - Brian W. Kernighan and Rob Pike (1999). A very good book to accompany K&R. It uses C++ and Java too.

  • C Traps and Pitfalls by A. Koenig (1989). Very good, but the C style pre-dates standard C, which makes it less recommendable these days.

    Some have argued for the removal of 'Traps and Pitfalls' from this list because it has trapped some people into making mistakes; others continue to argue for its inclusion. Perhaps it should be regarded as an 'expert' book because it requires a moderately extensive knowledge of C to understand what's changed since it was published.

  • MISRA-C - industry standard published and maintained by the Motor Industry Software Reliability Association. Covers C89 and C99.

    Although this isn't a book as such, many programmers recommend reading and implementing as much of it as possible. MISRA-C was originally intended as guidelines for safety-critical applications in particular, but it applies to any area of application where stable, bug-free C code is desired (who doesn't want fewer bugs?). MISRA-C is becoming the de facto standard in the whole embedded industry and is getting increasingly popular even in other programming branches. There are (at least) three publications of the standard (1998, 2004, and the current version from 2012). There is also a MISRA Compliance Guidelines document from 2016, and MISRA C:2012 Amendment 1 — Additional Security Guidelines for MISRA C:2012 (published in April 2016).

    Note that some of the strictures in the MISRA rules are not appropriate to every context. For example, directive 4.12 states "Dynamic memory allocation shall not be used". This is appropriate in the embedded systems for which the MISRA rules are designed; it is not appropriate everywhere. (Compilers, for instance, generally use dynamic memory allocation for things like symbol tables, and to do without dynamic memory allocation would be difficult, if not preposterous.)

  • Archived lists of ACCU-reviewed books on Beginner's C (116 titles) from 2007 and Advanced C (76 titles) from 2008. Most of these don't look to be on the main site anymore, and you can't browse that by subject anyway.


Warnings

There is a list of books and tutorials to be cautious about at the ISO 9899 Wiki, which is not itself formally associated with ISO or the C standard, but contains information about the C standard (though it hails the release of ISO 9899:2011 and does not mention the release of ISO 9899:2018).

Be wary of books written by Herbert Schildt. In particular, you should stay away from C: The Complete Reference (4th Edition, 2000), known in some circles as C: The Complete Nonsense.

Also do not use the book Let Us C (16th Edition, 2017) by Yashwant Kanetkar. Many people view it as an outdated book that teaches Turbo C and has lots of obsolete, misleading and incorrect material. For example, page 137 discusses the expected output from printf("%d %d %d\n", a, ++a, a++) and does not categorize it as undefined behaviour as it should. It also consistently promotes unportable and buggy coding practices, such as using gets, %[\n]s in scanf, storing return value of getchar in a variable of type char or using fflush on stdin.

Learn C The Hard Way (2015) by Zed Shaw. A book with mixed reviews. A critique of this book by Tim Hentenaar:

To summarize my views, which are laid out below, the author presents the material in a greatly oversimplified and misleading way, the whole corpus is a bundled mess, and some of the opinions and analyses he offers are just plain wrong. I've tried to view this book through the eyes of a novice, but unfortunately I am biased by years of experience writing code in C. It's obvious to me that either the author has a flawed understanding of C, or he's deliberately oversimplifying to the point where he's actually misleading the reader (intentionally or otherwise).

"Learn C The Hard Way" is not a book that I could recommend to someone who is both learning to program and learning C. If you're already a competent programmer in some other related language, then it represents an interesting and unusual exposition on C, though I have reservations about parts of the book. Jonathan Leffler


Outdated


Other contributors, not necessarily credited in the revision history, include:
Alex Lockwood, Ben Jackson, Bubbles, claws, coledot, Dana Robinson, Daniel Holden, desbest, Dervin Thunk, dwc, Erci Hou, Garen, haziz, Johan Bezem, Jonathan Leffler, Joshua Partogi, Lucas, Lundin, Matt K., mossplix, Matthieu M., midor, Nietzche-jou, Norman Ramsey, r3st0r3, ridthyself, Robert S. Barnes, Steve Summit, Tim Ring, Tony Bai, VMAtm

Twitter Bootstrap Responsive Background-Image inside Div

Don't use fixed:

.myimage {
   background:url(admin-user-bg.png) no-repeat top center;
   background: transparent url("yourimage.png") no-repeat top center fixed;
   -webkit-background-size: cover;
   -moz-background-size: cover;
   -o-background-size: cover;
   background-size: 100%;
   height: 500px;
}

What is the proper way to comment functions in Python?

The principles of good commenting are fairly subjective, but here are some guidelines:

  • Function comments should describe the intent of a function, not the implementation
  • Outline any assumptions that your function makes with regards to system state. If it uses any global variables (tsk, tsk), list those.
  • Watch out for excessive ASCII art. Having long strings of hashes may seem to make the comments easier to read, but they can be annoying to deal with when comments change
  • Take advantage of language features that provide 'auto documentation', i.e., docstrings in Python, POD in Perl, and Javadoc in Java

SQL Server Management Studio – tips for improving the TSQL coding process

For Sub Queries

object explorer > right-click a table > Script table as > SELECT to > Clipboard

Then you can just paste in the section where you want that as a sub query.

Templates / Snippets

Create you own templates with only a code snippet. Then instead opening the template as a new document just drag it to you current query to insert the snippet.

A snippet can simply be a set of header with comments or just some simple piece of code.

Implicit transactions

If you wont remember to start a transaction before your delete statemens you can go to options and set implicit transactions by default in all your queries. They require always an explicit commit / rollback.

Isolation level

Go to options and set isolation level to READ_UNCOMMITED by default. This way you dont need to type a NOLOCK in all your ad hoc queries. Just dont forget to place the table hint when writing a new view or stored procedure.

Default database

Your login has a default database set by the DBA (To me is usually the undesired one almost every time).

If you want it to be a different one because of the project you are currently working on.

In 'Registered Servers pane' > Right click > Properties > Connection properties tab > connect to database.

Multiple logins

(These you might already have done though)

Register the server multiple times, each with a different login. You can then have the same server in the object browser open multiple times (each with a different login).

To execute the same query you already wrote with a different login, instead of copying the query just do a right click over the query pane > Connection > Change connection.

How to override application.properties during production in Spring-Boot?

I am not sure you can dynamically change profiles.

Why not just have an internal properties file with the spring.config.location property set to your desired outside location, and the properties file at that location (outside the jar) have the spring.profiles.active property set?

Better yet, have an internal properties file, specific to dev profile (has spring.profiles.active=dev) and leave it like that, and when you want to deploy in production, specify a new location for your properties file, which has spring.profiles.active=prod:

java -jar myjar.jar --spring.config.location=D:\wherever\application.properties

How to enable DataGridView sorting when user clicks on the column header?

KISS : Keep it simple, stupid

Way A: Implement an own SortableBindingList class when like to use DataBinding and sorting.

Way B: Use a List<string> sorting works also but does not work with DataBinding.

C/C++ switch case with string

Just use a if() { } else if () { } chain. Using a hash value is going to be a maintenance nightmare. switch is intended to be a low-level statement which would not be appropriate for string comparisons.

Is it possible to apply CSS to half of a character?

You can use below code. Here in this example I have used h1 tag and added an attribute data-title-text="Display Text" which will appear with different color text on h1 tag text element, which gives effect halfcolored text as shown in below example

enter image description here

_x000D_
_x000D_
body {_x000D_
  text-align: center;_x000D_
  margin: 0;_x000D_
}_x000D_
_x000D_
h1 {_x000D_
  color: #111;_x000D_
  font-family: arial;_x000D_
  position: relative;_x000D_
  font-family: 'Oswald', sans-serif;_x000D_
  display: inline-block;_x000D_
  font-size: 2.5em;_x000D_
}_x000D_
_x000D_
h1::after {_x000D_
  content: attr(data-title-text);_x000D_
  color: #e5554e;_x000D_
  position: absolute;_x000D_
  left: 0;_x000D_
  top: 0;_x000D_
  clip: rect(0, 1000px, 30px, 0);_x000D_
}
_x000D_
<h1 data-title-text="Display Text">Display Text</h1>
_x000D_
_x000D_
_x000D_

How to add multiple jar files in classpath in linux

For linux users, you should know the following:

  1. $CLASSPATH is specifically what Java uses to look through multiple directories to find all the different classes it needs for your script (unless you explicitly tell it otherwise with the -cp override). Using -cp (--classpath) requires that you keep track of all the directories manually and copy-paste that line every time you run the program (not preferable IMO).

  2. The colon (":") character separates the different directories. There is only one $CLASSPATH and it has all the directories in it. So, when you run "export CLASSPATH=...." you want to include the current value "$CLASSPATH" in order to append to it. For example:

    export CLASSPATH=.
    export CLASSPATH=$CLASSPATH:/usr/share/java/mysql-connector-java-5.1.12.jar
    

    In the first line above, you start CLASSPATH out with just a simple 'dot' which is the path to your current working directory. With that, whenever you run java it will look in the current working directory (the one you're in) for classes. In the second line above, $CLASSPATH grabs the value that you previously entered (.) and appends the path to a mysql dirver. Now, java will look for the driver AND for your classes.

  3. echo $CLASSPATH
    

    is super handy, and what it returns should read like a colon-separated list of all the directories you want java looking in for what it needs to run your script.

  4. Tomcat does not use CLASSPATH. Read what to do about that here: https://tomcat.apache.org/tomcat-8.0-doc/class-loader-howto.html

Where to put default parameter value in C++?

Good question... I find that coders typically use the declaration to declare defaults. I've been held to one way (or warned) or the other too based on the compiler

void testFunct(int nVal1, int nVal2=500);
void testFunct(int nVal1, int nVal2)
{
    using namespace std;
    cout << nVal1 << << nVal2 << endl;
}

PHP Call to undefined function

Presently I am working on web services where my function is defined and it was throwing an error undefined function.I just added this in autoload.php in codeigniter

$autoload['helper'] = array('common','security','url');

common is the name of my controller.

Why doesn't Python have a sign function?

"copysign" is defined by IEEE 754, and part of the C99 specification. That's why it's in Python. The function cannot be implemented in full by abs(x) * sign(y) because of how it's supposed to handle NaN values.

>>> import math
>>> math.copysign(1, float("nan"))
1.0
>>> math.copysign(1, float("-nan"))
-1.0
>>> math.copysign(float("nan"), 1)
nan
>>> math.copysign(float("nan"), -1)
nan
>>> float("nan") * -1
nan
>>> float("nan") * 1
nan
>>> 

That makes copysign() a more useful function than sign().

As to specific reasons why IEEE's signbit(x) is not available in standard Python, I don't know. I can make assumptions, but it would be guessing.

The math module itself uses copysign(1, x) as a way to check if x is negative or non-negative. For most cases dealing with mathematical functions that seems more useful than having a sign(x) which returns 1, 0, or -1 because there's one less case to consider. For example, the following is from Python's math module:

static double
m_atan2(double y, double x)
{
        if (Py_IS_NAN(x) || Py_IS_NAN(y))
                return Py_NAN;
        if (Py_IS_INFINITY(y)) {
                if (Py_IS_INFINITY(x)) {
                        if (copysign(1., x) == 1.)
                                /* atan2(+-inf, +inf) == +-pi/4 */
                                return copysign(0.25*Py_MATH_PI, y);
                        else
                                /* atan2(+-inf, -inf) == +-pi*3/4 */
                                return copysign(0.75*Py_MATH_PI, y);
                }
                /* atan2(+-inf, x) == +-pi/2 for finite x */
                return copysign(0.5*Py_MATH_PI, y);

There you can clearly see that copysign() is a more effective function than a three-valued sign() function.

You wrote:

If I were a python designer, I would been the other way around: no cmp() builtin, but a sign()

That means you don't know that cmp() is used for things besides numbers. cmp("This", "That") cannot be implemented with a sign() function.

Edit to collate my additional answers elsewhere:

You base your justifications on how abs() and sign() are often seen together. As the C standard library does not contain a 'sign(x)' function of any sort, I don't know how you justify your views. There's an abs(int) and fabs(double) and fabsf(float) and fabsl(long) but no mention of sign. There is "copysign()" and "signbit()" but those only apply to IEEE 754 numbers.

With complex numbers, what would sign(-3+4j) return in Python, were it to be implemented? abs(-3+4j) return 5.0. That's a clear example of how abs() can be used in places where sign() makes no sense.

Suppose sign(x) were added to Python, as a complement to abs(x). If 'x' is an instance of a user-defined class which implements the __abs__(self) method then abs(x) will call x.__abs__(). In order to work correctly, to handle abs(x) in the same way then Python will have to gain a sign(x) slot.

This is excessive for a relatively unneeded function. Besides, why should sign(x) exist and nonnegative(x) and nonpositive(x) not exist? My snippet from Python's math module implementation shows how copybit(x, y) can be used to implement nonnegative(), which a simple sign(x) cannot do.

Python should support have better support for IEEE 754/C99 math function. That would add a signbit(x) function, which would do what you want in the case of floats. It would not work for integers or complex numbers, much less strings, and it wouldn't have the name you are looking for.

You ask "why", and the answer is "sign(x) isn't useful." You assert that it is useful. Yet your comments show that you do not know enough to be able to make that assertion, which means you would have to show convincing evidence of its need. Saying that NumPy implements it is not convincing enough. You would need to show cases of how existing code would be improved with a sign function.

And that it outside the scope of StackOverflow. Take it instead to one of the Python lists.

SQL: parse the first, middle and last name from a fullname field

Here's a stored procedure that will put the first word found into First Name, the last word into Last Name and everything in between into Middle Name.

create procedure [dbo].[import_ParseName]
(            
    @FullName nvarchar(max),
    @FirstName nvarchar(255) output,
    @MiddleName nvarchar(255) output,
    @LastName nvarchar(255)  output
)
as
begin

set @FirstName = ''
set @MiddleName = ''
set @LastName = ''  
set @FullName = ltrim(rtrim(@FullName))

declare @ReverseFullName nvarchar(max)
set @ReverseFullName = reverse(@FullName)

declare @lengthOfFullName int
declare @endOfFirstName int
declare @beginningOfLastName int

set @lengthOfFullName = len(@FullName)
set @endOfFirstName = charindex(' ', @FullName)
set @beginningOfLastName = @lengthOfFullName - charindex(' ', @ReverseFullName) + 1

set @FirstName = case when @endOfFirstName <> 0 
                      then substring(@FullName, 1, @endOfFirstName - 1) 
                      else ''
                 end

set @MiddleName = case when (@endOfFirstName <> 0 and @beginningOfLastName <> 0 and @beginningOfLastName > @endOfFirstName)
                       then ltrim(rtrim(substring(@FullName, @endOfFirstName , @beginningOfLastName - @endOfFirstName))) 
                       else ''
                  end

set @LastName = case when @beginningOfLastName <> 0 
                     then substring(@FullName, @beginningOfLastName + 1 , @lengthOfFullName - @beginningOfLastName)
                     else ''
                end

return

end 

And here's me calling it.

DECLARE @FirstName nvarchar(255),
        @MiddleName nvarchar(255),
        @LastName nvarchar(255)

EXEC    [dbo].[import_ParseName]
        @FullName = N'Scott The Other Scott Kowalczyk',
        @FirstName = @FirstName OUTPUT,
        @MiddleName = @MiddleName OUTPUT,
        @LastName = @LastName OUTPUT

print   @FirstName 
print   @MiddleName
print   @LastName 

output:

Scott
The Other Scott
Kowalczyk

Is it safe to delete the "InetPub" folder?

As long as you go into the IIS configuration and change the default location from %SystemDrive%\InetPub to %SystemDrive%\www for each of the services (web, ftp) there shouldn't be any problems. Of course, you can't protect against other applications that might install stuff into that directory by default, instead of checking the configuration.

My recommendation? Don't change it -- it's not that hard to live with, and it reduces the confusion level for the next person who has to administrate the machine.

How can you run a Java program without main method?

Applets from what I remember do not need a main method, though I am not sure they are technically a program.

Sorting a vector in descending order

Actually, the first one is a bad idea. Use either the second one, or this:

struct greater
{
    template<class T>
    bool operator()(T const &a, T const &b) const { return a > b; }
};

std::sort(numbers.begin(), numbers.end(), greater());

That way your code won't silently break when someone decides numbers should hold long or long long instead of int.

force css grid container to fill full screen of device

If you take advantage of width: 100vw; and height: 100vh;, the object with these styles applied will stretch to the full width and height of the device.

Also note, there are times padding and margins can get added to your view, by browsers and the like. I added a * global no padding and margins so you can see the difference. Keep this in mind.

_x000D_
_x000D_
*{_x000D_
  box-sizing: border-box;_x000D_
  padding: 0;_x000D_
  margin: 0;_x000D_
}_x000D_
.wrapper {_x000D_
  display: grid;_x000D_
  border-style: solid;_x000D_
  border-color: red;_x000D_
  grid-template-columns: repeat(3, 1fr);_x000D_
  grid-template-rows: repeat(3, 1fr);_x000D_
  grid-gap: 10px;_x000D_
  width: 100vw;_x000D_
  height: 100vh;_x000D_
}_x000D_
.one {_x000D_
  border-style: solid;_x000D_
  border-color: blue;_x000D_
  grid-column: 1 / 3;_x000D_
  grid-row: 1;_x000D_
}_x000D_
.two {_x000D_
  border-style: solid;_x000D_
  border-color: yellow;_x000D_
  grid-column: 2 / 4;_x000D_
  grid-row: 1 / 3;_x000D_
}_x000D_
.three {_x000D_
  border-style: solid;_x000D_
  border-color: violet;_x000D_
  grid-row: 2 / 5;_x000D_
  grid-column: 1;_x000D_
}_x000D_
.four {_x000D_
  border-style: solid;_x000D_
  border-color: aqua;_x000D_
  grid-column: 3;_x000D_
  grid-row: 3;_x000D_
}_x000D_
.five {_x000D_
  border-style: solid;_x000D_
  border-color: green;_x000D_
  grid-column: 2;_x000D_
  grid-row: 4;_x000D_
}_x000D_
.six {_x000D_
  border-style: solid;_x000D_
  border-color: purple;_x000D_
  grid-column: 3;_x000D_
  grid-row: 4;_x000D_
}
_x000D_
<html>_x000D_
<div class="wrapper">_x000D_
  <div class="one">One</div>_x000D_
  <div class="two">Two</div>_x000D_
  <div class="three">Three</div>_x000D_
  <div class="four">Four</div>_x000D_
  <div class="five">Five</div>_x000D_
  <div class="six">Six</div>_x000D_
</div>_x000D_
</html>
_x000D_
_x000D_
_x000D_

How to configure log4j with a properties file

I believe that the configure method expects an absolute path. Anyhow, you may also try to load a Properties object first:

Properties props = new Properties();
props.load(new FileInputStream("log4j.properties"));
PropertyConfigurator.configure(props);

If the properties file is in the jar, then you could do something like this:

Properties props = new Properties();
props.load(getClass().getResourceAsStream("/log4j.properties"));
PropertyConfigurator.configure(props);

The above assumes that the log4j.properties is in the root folder of the jar file.

mysqldump with create database line

Here is how to do dump the database (with just the schema):

mysqldump -u root -p"passwd" --no-data --add-drop-database --databases my_db_name | sed 's#/[*]!40000 DROP DATABASE IF EXISTS my_db_name;#' >my_db_name.sql

If you also want the data, remove the --no-data option.

Is there a vr (vertical rule) in html?

HTML has little to no vertical positioning due to typographic nature of content layout. Vertical Rule just doesn't fit its semantics.

shell script to remove a file if it already exist

You can use this:

#!/bin/bash

file="file_you_want_to_delete"

if [ -f "$file" ] ; then
    rm "$file"
fi

Saving awk output to variable

#!/bin/bash

variable=`ps -ef | grep "port 10 -" | grep -v "grep port 10 -" | awk '{printf $12}'`
echo $variable

Notice that there's no space after the equal sign.

You can also use $() which allows nesting and is readable.

How to use C++ in Go

Seems that currently SWIG is best solution for this:

http://www.swig.org/Doc2.0/Go.html

It supports inheritance and even allows to subclass C++ class with Go struct so when overridden methods are called in C++ code, Go code is fired.

Section about C++ in Go FAQ is updated and now mentions SWIG and no longer says "because Go is garbage-collected it will be unwise to do so, at least naively".

Numpy first occurrence of value greater than existing value

Arrays that have a constant step between elements

In case of a range or any other linearly increasing array you can simply calculate the index programmatically, no need to actually iterate over the array at all:

def first_index_calculate_range_like(val, arr):
    if len(arr) == 0:
        raise ValueError('no value greater than {}'.format(val))
    elif len(arr) == 1:
        if arr[0] > val:
            return 0
        else:
            raise ValueError('no value greater than {}'.format(val))

    first_value = arr[0]
    step = arr[1] - first_value
    # For linearly decreasing arrays or constant arrays we only need to check
    # the first element, because if that does not satisfy the condition
    # no other element will.
    if step <= 0:
        if first_value > val:
            return 0
        else:
            raise ValueError('no value greater than {}'.format(val))

    calculated_position = (val - first_value) / step

    if calculated_position < 0:
        return 0
    elif calculated_position > len(arr) - 1:
        raise ValueError('no value greater than {}'.format(val))

    return int(calculated_position) + 1

One could probably improve that a bit. I have made sure it works correctly for a few sample arrays and values but that doesn't mean there couldn't be mistakes in there, especially considering that it uses floats...

>>> import numpy as np
>>> first_index_calculate_range_like(5, np.arange(-10, 10))
16
>>> np.arange(-10, 10)[16]  # double check
6

>>> first_index_calculate_range_like(4.8, np.arange(-10, 10))
15

Given that it can calculate the position without any iteration it will be constant time (O(1)) and can probably beat all other mentioned approaches. However it requires a constant step in the array, otherwise it will produce wrong results.

General solution using numba

A more general approach would be using a numba function:

@nb.njit
def first_index_numba(val, arr):
    for idx in range(len(arr)):
        if arr[idx] > val:
            return idx
    return -1

That will work for any array but it has to iterate over the array, so in the average case it will be O(n):

>>> first_index_numba(4.8, np.arange(-10, 10))
15
>>> first_index_numba(5, np.arange(-10, 10))
16

Benchmark

Even though Nico Schlömer already provided some benchmarks I thought it might be useful to include my new solutions and to test for different "values".

The test setup:

import numpy as np
import math
import numba as nb

def first_index_using_argmax(val, arr):
    return np.argmax(arr > val)

def first_index_using_where(val, arr):
    return np.where(arr > val)[0][0]

def first_index_using_nonzero(val, arr):
    return np.nonzero(arr > val)[0][0]

def first_index_using_searchsorted(val, arr):
    return np.searchsorted(arr, val) + 1

def first_index_using_min(val, arr):
    return np.min(np.where(arr > val))

def first_index_calculate_range_like(val, arr):
    if len(arr) == 0:
        raise ValueError('empty array')
    elif len(arr) == 1:
        if arr[0] > val:
            return 0
        else:
            raise ValueError('no value greater than {}'.format(val))

    first_value = arr[0]
    step = arr[1] - first_value
    if step <= 0:
        if first_value > val:
            return 0
        else:
            raise ValueError('no value greater than {}'.format(val))

    calculated_position = (val - first_value) / step

    if calculated_position < 0:
        return 0
    elif calculated_position > len(arr) - 1:
        raise ValueError('no value greater than {}'.format(val))

    return int(calculated_position) + 1

@nb.njit
def first_index_numba(val, arr):
    for idx in range(len(arr)):
        if arr[idx] > val:
            return idx
    return -1

funcs = [
    first_index_using_argmax, 
    first_index_using_min, 
    first_index_using_nonzero,
    first_index_calculate_range_like, 
    first_index_numba, 
    first_index_using_searchsorted, 
    first_index_using_where
]

from simple_benchmark import benchmark, MultiArgument

and the plots were generated using:

%matplotlib notebook
b.plot()

item is at the beginning

b = benchmark(
    funcs,
    {2**i: MultiArgument([0, np.arange(2**i)]) for i in range(2, 20)},
    argument_name="array size")

enter image description here

The numba function performs best followed by the calculate-function and the searchsorted function. The other solutions perform much worse.

item is at the end

b = benchmark(
    funcs,
    {2**i: MultiArgument([2**i-2, np.arange(2**i)]) for i in range(2, 20)},
    argument_name="array size")

enter image description here

For small arrays the numba function performs amazingly fast, however for bigger arrays it's outperformed by the calculate-function and the searchsorted function.

item is at sqrt(len)

b = benchmark(
    funcs,
    {2**i: MultiArgument([np.sqrt(2**i), np.arange(2**i)]) for i in range(2, 20)},
    argument_name="array size")

enter image description here

This is more interesting. Again numba and the calculate function perform great, however this is actually triggering the worst case of searchsorted which really doesn't work well in this case.

Comparison of the functions when no value satisfies the condition

Another interesting point is how these function behave if there is no value whose index should be returned:

arr = np.ones(100)
value = 2

for func in funcs:
    print(func.__name__)
    try:
        print('-->', func(value, arr))
    except Exception as e:
        print('-->', e)

With this result:

first_index_using_argmax
--> 0
first_index_using_min
--> zero-size array to reduction operation minimum which has no identity
first_index_using_nonzero
--> index 0 is out of bounds for axis 0 with size 0
first_index_calculate_range_like
--> no value greater than 2
first_index_numba
--> -1
first_index_using_searchsorted
--> 101
first_index_using_where
--> index 0 is out of bounds for axis 0 with size 0

Searchsorted, argmax, and numba simply return a wrong value. However searchsorted and numba return an index that is not a valid index for the array.

The functions where, min, nonzero and calculate throw an exception. However only the exception for calculate actually says anything helpful.

That means one actually has to wrap these calls in an appropriate wrapper function that catches exceptions or invalid return values and handle appropriately, at least if you aren't sure if the value could be in the array.


Note: The calculate and searchsorted options only work in special conditions. The "calculate" function requires a constant step and the searchsorted requires the array to be sorted. So these could be useful in the right circumstances but aren't general solutions for this problem. In case you're dealing with sorted Python lists you might want to take a look at the bisect module instead of using Numpys searchsorted.

Multiple conditions with CASE statements

It's not a cut and paste. The CASE expression must return a value, and you are returning a string containing SQL (which is technically a value but of a wrong type). This is what you wanted to write, I think:

SELECT * FROM [Purchasing].[Vendor] WHERE  
CASE
  WHEN @url IS null OR @url = '' OR @url = 'ALL'
    THEN PurchasingWebServiceURL LIKE '%'
  WHEN @url = 'blank'
    THEN PurchasingWebServiceURL = ''
  WHEN @url = 'fail'
    THEN PurchasingWebServiceURL NOT LIKE '%treyresearch%'
  ELSE PurchasingWebServiceURL = '%' + @url + '%' 
END

I also suspect that this might not work in some dialects, but can't test now (Oracle, I'm looking at you), due to not having booleans.

However, since @url is not dependent on the table values, why not make three different queries, and choose which to evaluate based on your parameter?

ArrayList of String Arrays

Following works in Java 8..

List<String[]> addresses = new ArrayList<>();

Current date and time as string

#include <chrono>
#include <iostream>

int main()
{
    std::time_t ct = std::time(0);
    char* cc = ctime(&ct);

    std::cout << cc << std::endl;
    return 0;
}

Android SDK manager won't open

I encountered a similar problem where SDK manager would flash a command window and die.

This is what worked for me: My processor and OS both are 64-bit. I had installed 64-bit JDK version. The problem wouldn't go away with reinstalling JDK or modifying path. My theory was that SDK Manager may be needed 32-bit version of JDK. Don't know why that should matter but I ended up installing 32-bit version of JDK and magic. And SDK Manager successfully launched.

ssh "permissions are too open" error

On Windows 10, cygwin's chmod and chgrp weren't enough for me. I had to right click on the file -> Properties -> Security (tab) and remove all users and groups except for my active user.

XPath: Get parent node from child node

Just as an alternative, you can use ancestor.

//*[title="50"]/ancestor::store

It's more powerful than parent since it can get even the grandparent or great great grandparent

Python return statement error " 'return' outside function"

To break a loop, use break instead of return.

Or put the loop or control construct into a function, only functions can return values.

How to reset sequence in postgres and fill id column with new data?

With PostgreSQL 8.4 or newer there is no need to specify the WITH 1 anymore. The start value that was recorded by CREATE SEQUENCE or last set by ALTER SEQUENCE START WITH will be used (most probably this will be 1).

Reset the sequence:

ALTER SEQUENCE seq RESTART;

Then update the table's ID column:

UPDATE foo SET id = DEFAULT;

Source: PostgreSQL Docs

How do I conditionally add attributes to React components?

Here is an alternative.

var condition = true;

var props = {
  value: 'foo',
  ...( condition && { disabled: true } )
};

var component = <div { ...props } />;

Or its inline version

var condition = true;

var component = (
  <div
    value="foo"
    { ...( condition && { disabled: true } ) } />
);

Border around tr element doesn't show?

Add this to the stylesheet:

table {
  border-collapse: collapse;
}

JSFiddle.

The reason why it behaves this way is actually described pretty well in the specification:

There are two distinct models for setting borders on table cells in CSS. One is most suitable for so-called separated borders around individual cells, the other is suitable for borders that are continuous from one end of the table to the other.

... and later, for collapse setting:

In the collapsing border model, it is possible to specify borders that surround all or part of a cell, row, row group, column, and column group.

Html.BeginForm and adding properties

As part of htmlAttributes,e.g.

Html.BeginForm(
    action, controller, FormMethod.Post, new { enctype="multipart/form-data"})

Or you can pass null for action and controller to get the same default target as for BeginForm() without any parameters:

Html.BeginForm(
    null, null, FormMethod.Post, new { enctype="multipart/form-data"})

How to connect access database in c#

Try this code,

public void ConnectToAccess()
{
    System.Data.OleDb.OleDbConnection conn = new 
        System.Data.OleDb.OleDbConnection();
    // TODO: Modify the connection string and include any
    // additional required properties for your database.
    conn.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;" +
        @"Data source= C:\Documents and Settings\username\" +
        @"My Documents\AccessFile.mdb";
    try
    {
        conn.Open();
        // Insert code to process data.
    }
        catch (Exception ex)
    {
        MessageBox.Show("Failed to connect to data source");
    }
    finally
    {
        conn.Close();
    }
}

http://msdn.microsoft.com/en-us/library/5ybdbtte(v=vs.71).aspx

How to wait for a process to terminate to execute another process in batch file

This is an updated version of aphoria's Answer.

I Replaced PSLIST and PSEXEC with TASKKILL and TASKLIST`. As they seem to work better, I couldn't get PSLIST to run in Windows 7.

Also replaced Sleep with TIMEOUT.

This Was everything i needed to get the script running well, and all the additions was provided by the great guys who posted the comments.

Also if there is a delay before the .exe starts it might be worth inserting a Timeout before the :loop.

@ECHO OFF

TASKKILL NOTEPAD

START "" "C:\Program Files\Windows NT\Accessories\wordpad.exe"

:LOOP
tasklist | find /i "WORDPAD" >nul 2>&1
IF ERRORLEVEL 1 (
  GOTO CONTINUE
) ELSE (
  ECHO Wordpad is still running
  Timeout /T 5 /Nobreak
  GOTO LOOP
)

:CONTINUE
NOTEPAD

2D cross-platform game engine for Android and iOS?

I currently use Corona for business applications with great success. As far as games go, I'm under the impression that it doesn't provide the performance that some of the other cross-platform development engines do. It is worth noting that Carlos (founder of Ansca Mobile/Corona SDK) has started another company on a competing engine; Lanica Platino Engine for Appcelerator Titanium. While I haven't worked with this personally, it does look promising. Keep in mind, however, that it comes with a $999/yr price tag.

All that said, I have been researching Moai for a little while now (since I am already familiar with Lua syntax) and it does seem promising. The fact that it can compile for multiple platforms, not limited to mobile environments, is appealing.

Multimedia Fusion 2 is also a worth contender, considering the complexity of games produced and the performance realized from them. Vincere Totus Astrum (http://gamesare.com) comes to mind.

Subtract two dates in Java

Assuming that you're constrained to using Date, you can do the following:

Date diff = new Date(d2.getTime() - d1.getTime());

Here you're computing the differences in milliseconds since the "epoch", and creating a new Date object at an offset from the epoch. Like others have said: the answers in the duplicate question are probably better alternatives (if you aren't tied down to Date).

How can I strip first X characters from string using sed?

Chances are, you'll have cut as well. If so:

[me@home]$ echo "pid: 1234" | cut -d" " -f2
1234

Disable back button in android

Try this:

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
 if (keyCode == KeyEvent.KEYCODE_BACK) {

   return true;
 }
   return super.onKeyDown(keyCode, event);    
}

Schema validation failed with the following errors: Data path ".builders['app-shell']" should have required property 'class'

I got this issue when installing Bootstrap.

The following commands are what worked for me:

npm uninstall @angular-devkit/build-angular

npm install @angular-devkit/[email protected]

How to validate a url in Python? (Malformed or not)

Validate URL with urllib and Django-like regex

The Django URL validation regex was actually pretty good but I needed to tweak it a little bit for my use case. Feel free to adapt it to yours!

Python 3.7

import re
import urllib

# Check https://regex101.com/r/A326u1/5 for reference
DOMAIN_FORMAT = re.compile(
    r"(?:^(\w{1,255}):(.{1,255})@|^)" # http basic authentication [optional]
    r"(?:(?:(?=\S{0,253}(?:$|:))" # check full domain length to be less than or equal to 253 (starting after http basic auth, stopping before port)
    r"((?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+" # check for at least one subdomain (maximum length per subdomain: 63 characters), dashes in between allowed
    r"(?:[a-z0-9]{1,63})))" # check for top level domain, no dashes allowed
    r"|localhost)" # accept also "localhost" only
    r"(:\d{1,5})?", # port [optional]
    re.IGNORECASE
)
SCHEME_FORMAT = re.compile(
    r"^(http|hxxp|ftp|fxp)s?$", # scheme: http(s) or ftp(s)
    re.IGNORECASE
)

def validate_url(url: str):
    url = url.strip()

    if not url:
        raise Exception("No URL specified")

    if len(url) > 2048:
        raise Exception("URL exceeds its maximum length of 2048 characters (given length={})".format(len(url)))

    result = urllib.parse.urlparse(url)
    scheme = result.scheme
    domain = result.netloc

    if not scheme:
        raise Exception("No URL scheme specified")

    if not re.fullmatch(SCHEME_FORMAT, scheme):
        raise Exception("URL scheme must either be http(s) or ftp(s) (given scheme={})".format(scheme))

    if not domain:
        raise Exception("No URL domain specified")

    if not re.fullmatch(DOMAIN_FORMAT, domain):
        raise Exception("URL domain malformed (domain={})".format(domain))

    return url

Explanation

  • The code only validates the scheme and netloc part of a given URL. (To do this properly, I split the URL with urllib.parse.urlparse() in the two according parts which are then matched with the corresponding regex terms.)
  • The netloc part stops before the first occurrence of a slash /, so port numbers are still part of the netloc, e.g.:

    https://www.google.com:80/search?q=python
    ^^^^^   ^^^^^^^^^^^^^^^^^
      |             |      
      |             +-- netloc (aka "domain" in my code)
      +-- scheme
    
  • IPv4 addresses are also validated

IPv6 Support

If you want the URL validator to also work with IPv6 addresses, do the following:

  • Add is_valid_ipv6(ip) from Markus Jarderot's answer, which has a really good IPv6 validator regex
  • Add and not is_valid_ipv6(domain) to the last if

Examples

Here are some examples of the regex for the netloc (aka domain) part in action:

How do I edit a file after I shell to a Docker container?

You can use cat if installed, with the > caracter. Here is the manipulation :

cat > file_to_edit
#1 Write or Paste you text
#2 don't forget to leave a blank line at the end of file
#3 Ctrl + C to apply configuration

Now you can see the result with the command

cat file

How to pass parameter to function using in addEventListener?

In the first line of your JS code:

select.addEventListener('change', getSelection(this), false);

you're invoking getSelection by placing (this) behind the function reference. That is most likely not what you want, because you're now passing the return value of that call to addEventListener, instead of a reference to the actual function itself.


In a function invoked by addEventListener the value for this will automatically be set to the object the listener is attached to, productLineSelect in this case.

If that is what you want, you can just pass the function reference and this will in this example be select in invocations from addEventListener:

select.addEventListener('change', getSelection, false);

If that is not what you want, you'd best bind your value for this to the function you're passing to addEventListener:

var thisArg = { custom: 'object' };
select.addEventListener('change', getSelection.bind(thisArg), false);

The .bind part is also a call, but this call just returns the same function we're calling bind on, with the value for this inside that function scope fixed to thisArg, effectively overriding the dynamic nature of this-binding.


To get to your actual question: "How to pass parameters to function in addEventListener?"

You would have to use an additional function definition:

var globalVar = 'global';

productLineSelect.addEventListener('change', function(event) {
    var localVar = 'local';
    getSelection(event, this, globalVar, localVar);
}, false);

Now we pass the event object, a reference to the value of this inside the callback of addEventListener, a variable defined and initialised inside that callback, and a variable from outside the entire addEventListener call to your own getSelection function.


We also might again have an object of our choice to be this inside the outer callback:

var thisArg = { custom: 'object' };
var globalVar = 'global';

productLineSelect.addEventListener('change', function(event) {
    var localVar = 'local';
    getSelection(event, this, globalVar, localVar);
}.bind(thisArg), false);

Why do I get a C malloc assertion failure?

I got the following message, similar to your one:


    program: malloc.c:2372: sysmalloc: Assertion `(old_top == (((mbinptr) (((char *) &((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct malloc_chunk, fd)))) && old_size == 0) || ((unsigned long) (old_size) >= (unsigned long)((((__builtin_offsetof (struct malloc_chunk, fd_nextsize))+((2 *(sizeof(size_t))) - 1)) & ~((2 *(sizeof(size_t))) - 1))) && ((old_top)->size & 0x1) && ((unsigned long) old_end & pagemask) == 0)' failed.

Made a mistake some method call before, when using malloc. Erroneously overwrote the multiplication sign '*' with a '+', when updating the factor after sizeof()-operator on adding a field to unsigned char array.

Here is the code responsible for the error in my case:


    UCHAR* b=(UCHAR*)malloc(sizeof(UCHAR)+5);
    b[INTBITS]=(some calculation);
    b[BUFSPC]=(some calculation);
    b[BUFOVR]=(some calculation);
    b[BUFMEM]=(some calculation);
    b[MATCHBITS]=(some calculation);

In another method later, I used malloc again and it produced the error message shown above. The call was (simple enough):


    UCHAR* b=(UCHAR*)malloc(sizeof(UCHAR)*50);

Think using the '+'-sign on the 1st call, which lead to mis-calculus in combination with immediate initialization of the array after (overwriting memory that was not allocated to the array), brought some confusion to malloc's memory map. Therefore the 2nd call went wrong.

How to delete and recreate from scratch an existing EF Code First database

Let me help in updating the answers here since new users will find it useful. I believe the aim is to delete the database itself and recreate it using EF Code First approach. 1.Open your project in Visual Studio using the ".sln" extention. 2.Select Server Explorer( it is oftentimes on the left) 3.Select SQL Server Object Explorer. 4.The database you want to delete would be listed under any of the localDB. Right-Click it and select delete.

Python __call__ special method practical example

I find it useful because it allows me to create APIs that are easy to use (you have some callable object that requires some specific arguments), and are easy to implement because you can use Object Oriented practices.

The following is code I wrote yesterday that makes a version of the hashlib.foo methods that hash entire files rather than strings:

# filehash.py
import hashlib


class Hasher(object):
    """
    A wrapper around the hashlib hash algorithms that allows an entire file to
    be hashed in a chunked manner.
    """
    def __init__(self, algorithm):
        self.algorithm = algorithm

    def __call__(self, file):
        hash = self.algorithm()
        with open(file, 'rb') as f:
            for chunk in iter(lambda: f.read(4096), ''):
                hash.update(chunk)
        return hash.hexdigest()


md5    = Hasher(hashlib.md5)
sha1   = Hasher(hashlib.sha1)
sha224 = Hasher(hashlib.sha224)
sha256 = Hasher(hashlib.sha256)
sha384 = Hasher(hashlib.sha384)
sha512 = Hasher(hashlib.sha512)

This implementation allows me to use the functions in a similar fashion to the hashlib.foo functions:

from filehash import sha1
print sha1('somefile.txt')

Of course I could have implemented it a different way, but in this case it seemed like a simple approach.

html5 - canvas element - Multiple layers

Related to this:

If you have something on your canvas and you want to draw something at the back of it - you can do it by changing the context.globalCompositeOperation setting to 'destination-over' - and then return it to 'source-over' when you're done.

_x000D_
_x000D_
   var context = document.getElementById('cvs').getContext('2d');_x000D_
_x000D_
    // Draw a red square_x000D_
    context.fillStyle = 'red';_x000D_
    context.fillRect(50,50,100,100);_x000D_
_x000D_
_x000D_
_x000D_
    // Change the globalCompositeOperation to destination-over so that anything_x000D_
    // that is drawn on to the canvas from this point on is drawn at the back_x000D_
    // of what's already on the canvas_x000D_
    context.globalCompositeOperation = 'destination-over';_x000D_
_x000D_
_x000D_
_x000D_
    // Draw a big yellow rectangle_x000D_
    context.fillStyle = 'yellow';_x000D_
    context.fillRect(0,0,600,250);_x000D_
_x000D_
_x000D_
    // Now return the globalCompositeOperation to source-over and draw a_x000D_
    // blue rectangle_x000D_
    context.globalCompositeOperation = 'source-over';_x000D_
_x000D_
    // Draw a blue rectangle_x000D_
    context.fillStyle = 'blue';_x000D_
    context.fillRect(75,75,100,100);
_x000D_
<canvas id="cvs" />
_x000D_
_x000D_
_x000D_

Mapping a JDBC ResultSet to an object

No need of storing resultSet values into String and again setting into POJO class. Instead set at the time you are retrieving.

Or best way switch to ORM tools like hibernate instead of JDBC which maps your POJO object direct to database.

But as of now use this:

List<User> users=new ArrayList<User>();

while(rs.next()) {
   User user = new User();      
   user.setUserId(rs.getString("UserId"));
   user.setFName(rs.getString("FirstName"));
  ...
  ...
  ...


  users.add(user);
} 

jQuery .get error response function?

If you want a generic error you can setup all $.ajax() (which $.get() uses underneath) requests jQuery makes to display an error using $.ajaxSetup(), for example:

$.ajaxSetup({
  error: function(xhr, status, error) {
    alert("An AJAX error occured: " + status + "\nError: " + error);
  }
});

Just run this once before making any AJAX calls (no changes to your current code, just stick this before somewhere). This sets the error option to default to the handler/function above, if you made a full $.ajax() call and specified the error handler then what you had would override the above.

Angular 2 change event on every keypress

<input type="text" (keypress)="myMethod(myInput.value)" #myInput />

archive .ts

myMethod(value:string){
...
...
}

Cannot make file java.io.IOException: No such file or directory

i fixed my problem by this code on linux file system

if (!file.exists())
    Files.createFile(file.toPath());

How to set Angular 4 background image?

I wanted a profile picture of size 96x96 with data from api. The following solution worked for me in project Angular 7.

.ts:

  @Input() profile;

.html:

 <span class="avatar" [ngStyle]="{'background-image': 'url('+ profile?.public_picture +')'}"></span>

.scss:

 .avatar {
      border-radius: 100%;
      background-size: cover;
      background-position: center center;
      background-repeat: no-repeat;
      width: 96px;
      height: 96px;
    }

Please note that if you write background instead of 'background-image' in [ngStyle], the styles you write (even in style of element) for other background properties like background-position/size, etc. won't work. Because you will already fix it's properties with background: 'url(+ property +) (no providers for size, position, etc. !)'. The [ngStyle] priority is higher than style of element. In background here, only url() property will work. Be sure to use 'background-image' instead of 'background'in case you want to write more properties to background image.

How to ping a server only once from within a batch file?

Just write the command "ping your server IP" without the double quote. save file name as filename.bat and then run the batch file as administrator

How to convert a String to CharSequence?

Since String IS-A CharSequence, you can pass a String wherever you need a CharSequence, or assign a String to a CharSequence:

CharSequence cs = "string";
String s = cs.toString();
foo(s); // prints "string"

public void foo(CharSequence cs) { 
  System.out.println(cs);
}

If you want to convert a CharSequence to a String, just use the toString method that must be implemented by every concrete implementation of CharSequence.

Hope it helps.

Display filename before matching line

This is a slight modification from a previous solution. My example looks for stderr redirection in bash scripts: grep '2>' $(find . -name "*.bash")

how to get current location in google map android

public class MainActivity extends ActionBarActivity implements
    ConnectionCallbacks, OnConnectionFailedListener {
...
@Override
public void onConnected(Bundle connectionHint) {
    mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
            mGoogleApiClient);
    if (mLastLocation != null) {
        mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
        mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
    }
}
}

How to change the map center in Leaflet.js

For example:

map.panTo(new L.LatLng(40.737, -73.923));

How to count number of files in each directory?

find . -type f -printf '%h\n' | sort | uniq -c

gives for example:

  5 .
  4 ./aln
  5 ./aln/iq
  4 ./bs
  4 ./ft
  6 ./hot

Node.js: Python not found exception due to node-sass and node-gyp

Node-sass tries to download the binary for you platform when installing. Node 5 is supported by 3.8 https://github.com/sass/node-sass/releases/tag/v3.8.0 If your Jenkins can't download the prebuilt binary, then you need to follow the platform requirements on Node-gyp README (Python2, VS or MSBuild, ...) If possible I'd suggest updating your Node to at least 6 since 5 isn't supported by Node anymore. If you want to upgrade to 8, you'll need to update node-sass to 4.5.3

Eclipse - Failed to load class "org.slf4j.impl.StaticLoggerBinder"

Did you update the project (right-click on the project, "Maven" > "Update project...")? Otherwise, you need to check if pom.xml contains the necessary slf4j dependencies, e.g.:

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>jcl-over-slf4j</artifactId>
        <version>1.7.0</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.0</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.0</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.14</version>
    </dependency>

CSS disable hover effect

I tried the following and it works for me better

Code:

.unstyled-link{ 
  color: inherit;
  text-decoration: inherit;
  &:link,
  &:hover {
    color: inherit;
    text-decoration: inherit;
  }
}

Android requires compiler compliance level 5.0 or 6.0. Found '1.7' instead. Please use Android Tools > Fix Project Properties

i come across this problem cause my debug.keystore is expired, so i deleted the debug.keystore under .android folder, and the eclipse will regenerate a new debug.keystore, then i fixed th

PHP/Apache: PHP Fatal error: Call to undefined function mysql_connect()

In case anyone else faces this, it's a case of PHP not having access to the mysql client libraries. Having a MySQL server on the system is not the correct fix. Fix for ubuntu (and PHP 5):

sudo apt-get install php5-mysql

After installing the client, the webserver should be restarted. In case you're using apache, the following should work:

sudo service apache2 restart

Create multiple threads and wait all of them to complete

I've made a very simple extension method to wait for all threads of a collection:

using System.Collections.Generic;
using System.Threading;

namespace Extensions
{
    public static class ThreadExtension
    {
        public static void WaitAll(this IEnumerable<Thread> threads)
        {
            if(threads!=null)
            {
                foreach(Thread thread in threads)
                { thread.Join(); }
            }
        }
    }
}

Then you simply call:

List<Thread> threads=new List<Thread>();
// Add your threads to this collection
threads.WaitAll();

Why do Twitter Bootstrap tables always have 100% width?

<table style="width: auto;" ... works fine. Tested in Chrome 38 , IE 11 and Firefox 34.

jsfiddle : http://jsfiddle.net/rpaul/taqodr8o/

jquery find class and get the value

Class selectors are prefixed with a dot. Your .find() is missing that so jQuery thinks you're looking for <myClass> elements.

var myVar = $("#start").find('.myClass').val();

How to Create a script via batch file that will uninstall a program if it was installed on windows 7 64-bit or 32-bit

In my experience, to use wmic in a script, you need to get the nested quoting right:

wmic product where "name = 'Windows Azure Authoring Tools - v2.3'" call uninstall /nointeractive 

quoting both the query and the name. But wmic will only uninstall things installed via windows installer.

In Perl, how can I read an entire file into a string?

With File::Slurp:

use File::Slurp;
my $text = read_file('index.html');

Yes, even you can use CPAN.

How do you replace all the occurrences of a certain character in a string?

The problem is you're not doing anything with the result of replace. In Python strings are immutable so anything that manipulates a string returns a new string instead of modifying the original string.

line[8] = line[8].replace(letter, "")

How to assign colors to categorical variables in ggplot2 that have stable mapping?

This is an old post, but I was looking for answer to this same question,

Why not try something like:

scale_color_manual(values = c("foo" = "#999999", "bar" = "#E69F00"))

If you have categorical values, I don't see a reason why this should not work.

How to execute two mysql queries as one in PHP/MYSQL?

Yes it is possible without using MySQLi extension.

Simply use CLIENT_MULTI_STATEMENTS in mysql_connect's 5th argument.

Refer to the comments below Husni's post for more information.

Openssl is not recognized as an internal or external command

Steps to create Hash Key. 
1: Download openssl from Openssl for Windows . I downloaded the Win64 version 
2:Unzip and copy all the files in the bin folder including openssl.exe(All file of bin folder) 
3:Goto to the folder where you installed JDK for me it’s C:\Program Files\Java\jdk1.8.0_05\bin 
4:Paste all the files you copied from Openssl’s bin folder to the Jdk folder. 

then go C:\Program Files\Java\jdk1.8.0_05\bin and press shift key and right click and open cmd

C:\Program Files\Java\jdk1.8.0_05\bin>//cmd path 

that is for Sha1 past this
keytool -exportcert -alias androiddebugkey -keystore "C:\User\ABC\.android.keystore" | openssl sha1 -binary | openssl base64
//and ABC is system name put own system name

Firebug like plugin for Safari browser

Other than the builtin developer tools, there is none that i know of. You might, however, be able to use Firebug Lite.

Postgresql 9.2 pg_dump version mismatch

Well, I had the same issue as I have two postgress versions installed.

Just use the proper pg_dump and you don't need to change anything, in your case:

 $> /usr/lib/postgresql/9.2/bin/pg_dump books > books.out

"Data too long for column" - why?

Turns out, as is often the case, it was a stupid error on my part. The way I was testing this, I wasn't rebuilding the Department table after changing the data type from varchar(50) to varchar(200); I was just re-running the insert command, still with the column as varchar(50).

Remove all spaces from a string in SQL Server

Check and Try the below script (Unit Tested)-

--Declaring
DECLARE @Tbl TABLE(col_1 VARCHAR(100));

--Test Samples
INSERT INTO @Tbl (col_1)
VALUES
('  EY     y            
Salem')
, ('  EY     P    ort       Chennai   ')
, ('  EY     Old           Park   ')
, ('  EY   ')
, ('  EY   ')
,(''),(null),('d                           
    f');

SELECT col_1 AS INPUT,
    LTRIM(RTRIM(
    REPLACE(
    REPLACE(
    REPLACE(
    REPLACE(
    REPLACE(
        REPLACE(
        REPLACE(
        REPLACE(
        REPLACE(
        REPLACE(
        REPLACE(col_1,CHAR(10),' ')
        ,CHAR(11),' ')
        ,CHAR(12),' ')
        ,CHAR(13),' ')
        ,CHAR(14),' ')
        ,CHAR(160),' ')
        ,CHAR(13)+CHAR(10),' ')
    ,CHAR(9),' ')
    ,' ',CHAR(17)+CHAR(18))
    ,CHAR(18)+CHAR(17),'')
    ,CHAR(17)+CHAR(18),' ')
    )) AS [OUTPUT]
FROM @Tbl;

Rails ActiveRecord date between

Comment.find(:all, :conditions =>["date(created_at) BETWEEN ? AND ? ", '2011-11-01','2011-11-15'])

Simulating Button click in javascript

To simulate an event, you could to use trigger JQuery functionnality.

$('#foo').on('click', function() {
      alert($(this).text());
    });
$('#foo').trigger('click');

Displaying a vector of strings in C++

You have to insert the elements using the insert method present in vectors STL, check the below program to add the elements to it, and you can use in the same way in your program.

#include <iostream>
#include <vector>
#include <string.h>

int main ()
{
  std::vector<std::string> myvector ;
  std::vector<std::string>::iterator it;

   it = myvector.begin();
  std::string myarray [] = { "Hi","hello","wassup" };
  myvector.insert (myvector.begin(), myarray, myarray+3);

  std::cout << "myvector contains:";
  for (it=myvector.begin(); it<myvector.end(); it++)
    std::cout << ' ' << *it;
    std::cout << '\n';

  return 0;
}

ProgressDialog is deprecated.What is the alternate one to use?

ProgressBar is very simple and easy to use, i am intending to make this same as simple progress dialog. first step is that you can make xml layout of the dialog that you want to show, let say we name this layout

layout_loading_dialog.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:padding="20dp">
    <ProgressBar
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1" />

    <TextView
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="4"
        android:gravity="center"
        android:text="Please wait! This may take a moment." />
</LinearLayout>

next step is create AlertDialog which will show this layout with ProgressBar

AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setCancelable(false); // if you want user to wait for some process to finish,
builder.setView(R.layout.layout_loading_dialog);
AlertDialog dialog = builder.create();

now all that is left is to show and hide this dialog in our click events like this

dialog.show(); // to show this dialog
dialog.dismiss(); // to hide this dialog

and thats it, it should work, as you can see it is farely simple and easy to implement ProgressBar instead of ProgressDialog. now you can show/dismiss this dialog box in either Handler or ASyncTask, its up to your need

How to overwrite existing files in batch?

Add /Y to the command line

Is there an arraylist in Javascript?

In Java script you declare array as below:

var array=[];
array.push();

and for arraylist or object or array you have to use json; and Serialize it using json by using following code:

 var serializedMyObj = JSON.stringify(myObj);

What's the best way to identify hidden characters in the result of a query in SQL Server (Query Analyzer)?

Create a function that addresses all the whitespace possibilites and enable only those that seem appropriate:

SELECT dbo.ShowWhiteSpace(myfield) from mytable

Uncomment only those whitespace cases you want to test for:


CREATE FUNCTION dbo.ShowWhiteSpace (@str varchar(8000))
RETURNS varchar(8000)
AS
BEGIN
     DECLARE @ShowWhiteSpace varchar(8000);
     SET @ShowWhiteSpace = @str
     SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(32), '[?]')
     SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(13), '[CR]')
     SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(10), '[LF]')
     SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(9),  '[TAB]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(1),  '[SOH]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(2),  '[STX]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(3),  '[ETX]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(4),  '[EOT]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(5),  '[ENQ]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(6),  '[ACK]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(7),  '[BEL]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(8),  '[BS]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(11), '[VT]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(12), '[FF]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(14), '[SO]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(15), '[SI]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(16), '[DLE]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(17), '[DC1]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(18), '[DC2]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(19), '[DC3]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(20), '[DC4]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(21), '[NAK]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(22), '[SYN]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(23), '[ETB]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(24), '[CAN]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(25), '[EM]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(26), '[SUB]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(27), '[ESC]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(28), '[FS]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(29), '[GS]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(30), '[RS]')
--   SET @ShowWhiteSpace = REPLACE( @ShowWhiteSpace, CHAR(31), '[US]')
     RETURN(@ShowWhiteSpace)
END

How to convert a single char into an int

Any problems with the following way of doing it?

int CharToInt(const char c)
{
    switch (c)
    {
    case '0':
        return 0;
    case '1':
        return 1;
    case '2':
        return 2;
    case '3':
        return 3;
    case '4':
        return 4;
    case '5':
        return 5;
    case '6':
        return 6;
    case '7':
        return 7;
    case '8':
        return 8;
    case '9':
        return 9;
    default:
        return 0;
    }
}

UITableViewCell Selected Background Color on Multiple Selection

By adding a custom view with the background color of your own you can have a custom selection style in table view.

let customBGColorView = UIView()
customBGColorView.backgroundColor = UIColor(hexString: "#FFF900")
cellObj.selectedBackgroundView = customBGColorView

Add this 3 line code in cellForRowAt method of TableView. I have used an extension in UIColor to add color with hexcode. Put this extension code at the end of any Class(Outside the class's body).

extension UIColor {    
convenience init(hexString: String) {
    let hex = hexString.trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
    var int = UInt32()
    Scanner(string: hex).scanHexInt32(&int)
    let a, r, g, b: UInt32
    switch hex.characters.count {
    case 3: // RGB (12-bit)
        (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
    case 6: // RGB (24-bit)
        (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
    case 8: // ARGB (32-bit)
        (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
    default:
        (a, r, g, b) = (255, 0, 0, 0)
    }
    self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255)
  }
}

How to show "if" condition on a sequence diagram?

Very simple , using Alt fragment

Lets take an example of sequence diagram for an ATM machine.Let's say here you want

IF card inserted is valid then prompt "Enter Pin"....ELSE prompt "Invalid Pin"

Then here is the sequence diagram for the same

ATM machine sequence diagram

Hope this helps!

How do you roll back (reset) a Git repository to a particular commit?

Update:

Because of changes to how tracking branches are created and pushed I no longer recommend renaming branches. This is what I recommend now:

Make a copy of the branch at its current state:

git branch crazyexperiment

(The git branch <name> command will leave you with your current branch still checked out.)

Reset your current branch to your desired commit with git reset:

git reset --hard c2e7af2b51

(Replace c2e7af2b51 with the commit that you want to go back to.)

When you decide that your crazy experiment branch doesn't contain anything useful, you can delete it with:

git branch -D crazyexperiment

It's always nice when you're starting out with history-modifying git commands (reset, rebase) to create backup branches before you run them. Eventually once you're comfortable you won't find it necessary. If you do modify your history in a way that you don't want and haven't created a backup branch, look into git reflog. Git keeps commits around for quite a while even if there are no branches or tags pointing to them.

Original answer:

A slightly less scary way to do this than the git reset --hard method is to create a new branch. Let's assume that you're on the master branch and the commit you want to go back to is c2e7af2b51.

Rename your current master branch:

git branch -m crazyexperiment

Check out your good commit:

git checkout c2e7af2b51

Make your new master branch here:

git checkout -b master

Now you still have your crazy experiment around if you want to look at it later, but your master branch is back at your last known good point, ready to be added to. If you really want to throw away your experiment, you can use:

git branch -D crazyexperiment

MySQL high CPU usage

First I'd say you probably want to turn off persistent connections as they almost always do more harm than good.

Secondly I'd say you want to double check your MySQL users, just to make sure it's not possible for anyone to be connecting from a remote server. This is also a major security thing to check.

Thirdly I'd say you want to turn on the MySQL Slow Query Log to keep an eye on any queries that are taking a long time, and use that to make sure you don't have any queries locking up key tables for too long.

Some other things you can check would be to run the following query while the CPU load is high:

SHOW PROCESSLIST;

This will show you any queries that are currently running or in the queue to run, what the query is and what it's doing (this command will truncate the query if it's too long, you can use SHOW FULL PROCESSLIST to see the full query text).

You'll also want to keep an eye on things like your buffer sizes, table cache, query cache and innodb_buffer_pool_size (if you're using innodb tables) as all of these memory allocations can have an affect on query performance which can cause MySQL to eat up CPU.

You'll also probably want to give the following a read over as they contain some good information.

It's also a very good idea to use a profiler. Something you can turn on when you want that will show you what queries your application is running, if there's duplicate queries, how long they're taking, etc, etc. An example of something like this is one I've been working on called PHP Profiler but there are many out there. If you're using a piece of software like Drupal, Joomla or Wordpress you'll want to ask around within the community as there's probably modules available for them that allow you to get this information without needing to manually integrate anything.

Run chrome in fullscreen mode on Windows

You can also add --disable-session-crashed-bubble to eliminate the errors that come up after a crash or improper shutdown.

How do I get ASP.NET Web API to return JSON instead of XML using Chrome?

Have a look at content negotiation in the WebAPI. These (Part 1 & Part 2) wonderfully detailed and thorough blog posts explain how it works.

In short, you are right, and just need to set the Accept or Content-Type request headers. Given your Action isn't coded to return a specific format, you can set Accept: application/json.

Python: How to convert datetime format?

@Tim's answer only does half the work -- that gets it into a datetime.datetime object.

To get it into the string format you require, you use datetime.strftime:

print(datetime.strftime('%b %d,%Y'))

Create XML in Javascript

this work for me..

var xml  = parser.parseFromString('<?xml version="1.0" encoding="utf-8"?><root></root>', "application/xml");

developer.mozilla.org/en-US/docs/Web/API/DOMParser

Spring Boot: How can I set the logging level with application.properties?

You can do that using your application.properties.

logging.level.=ERROR -> Sets the root logging level to error
...
logging.level.=DEBUG -> Sets the root logging level to DEBUG

logging.file=${java.io.tmpdir}/myapp.log -> Sets the absolute log file path to TMPDIR/myapp.log

A sane default set of application.properties regarding logging using profiles would be: application.properties:

spring.application.name=<your app name here>
logging.level.=ERROR
logging.file=${java.io.tmpdir}/${spring.application.name}.log

application-dev.properties:

logging.level.=DEBUG
logging.file=

When you develop inside your favourite IDE you just add a -Dspring.profiles.active=dev as VM argument to the run/debug configuration of your app.

This will give you error only logging in production and debug logging during development WITHOUT writing the output to a log file. This will improve the performance during development ( and save SSD drives some hours of operation ;) ).

C - error: storage size of ‘a’ isn’t known

correct typo of

struct xyz a;

to

struct xyx a;

Better you can try typedef, easy to b

How to use @Nullable and @Nonnull annotations more effectively?

In Java I'd use Guava's Optional type. Being an actual type you get compiler guarantees about its use. It's easy to bypass it and obtain a NullPointerException, but at least the signature of the method clearly communicates what it expects as an argument or what it might return.

@AspectJ pointcut for all methods of a class with specific annotation

The simplest way seems to be :

@Around("execution(@MyHandling * com.exemple.YourService.*(..))")
public Object aroundServiceMethodAdvice(final ProceedingJoinPoint pjp)
   throws Throwable {
   // perform actions before

   return pjp.proceed();

   // perform actions after
}

It will intercept execution of all methods specifically annotated with '@MyHandling' in 'YourService' class. To intercept all methods without exception, just put the annotation directly on the class.

No matter of the private / public scope here, but keep in mind that spring-aop cannot use aspect for method calls in same instance (typically private ones), because it doesn't use the proxy class in this case.

We use @Around advice here, but it's basically the same syntax with @Before, @After or any advice.

By the way, @MyHandling annotation must be configured like this :

@Retention(RetentionPolicy.RUNTIME)
@Target( { ElementType.METHOD, ElementType.TYPE })
public @interface MyHandling {

}

Using set_facts and with_items together in Ansible

Updated 2018-06-08: My previous answer was a bit of hack so I have come back and looked at this again. This is a cleaner Jinja2 approach.

- name: Set fact 4
  set_fact:
    foo: "{% for i in foo_result.results %}{% do foo.append(i) %}{% endfor %}{{ foo }}"

I am adding this answer as current best answer for Ansible 2.2+ does not completely cover the original question. Thanks to Russ Huguley for your answer this got me headed in the right direction but it left me with a concatenated string not a list. This solution gets a list but becomes even more hacky. I hope this gets resolved in a cleaner manner.

- name: build foo_string
  set_fact:
    foo_string: "{% for i in foo_result.results %}{{ i.ansible_facts.foo_item }}{% if not loop.last %},{% endif %}{%endfor%}"

- name: set fact foo
  set_fact:
    foo: "{{ foo_string.split(',') }}"

[Ljava.lang.Object; cannot be cast to

In case entire entity is being return, better solution in spring JPA is use @Query(value = "from entity where Id in :ids")

This return entity type rather than object type

How to combine two byte arrays

Assuming your byteData array is biger than 32 + byteSalt.length()...you're going to it's length, not byteSalt.length. You're trying to copy from beyond the array end.

How to connect to a remote MySQL database with Java?

in my.cnf file , please change the following

## Instead of skip-networking the default is now to listen only on ## localhost which is more compatible and is not less secure. ## bind-address = 127.0.0.1

URL for public Amazon S3 bucket

The URL structure you're referring to is called the REST endpoint, as opposed to the Web Site Endpoint.


Note: Since this answer was originally written, S3 has rolled out dualstack support on REST endpoints, using new hostnames, while leaving the existing hostnames in place. This is now integrated into the information provided, below.


If your bucket is really in the us-east-1 region of AWS -- which the S3 documentation formerly referred to as the "US Standard" region, but was subsequently officially renamed to the "U.S. East (N. Virginia) Region" -- then http://s3-us-east-1.amazonaws.com/bucket/ is not the correct form for that endpoint, even though it looks like it should be. The correct format for that region is either http://s3.amazonaws.com/bucket/ or http://s3-external-1.amazonaws.com/bucket/

The format you're using is applicable to all the other S3 regions, but not US Standard US East (N. Virginia) [us-east-1].

S3 now also has dual-stack endpoint hostnames for the REST endpoints, and unlike the original endpoint hostnames, the names of these have a consistent format across regions, for example s3.dualstack.us-east-1.amazonaws.com. These endpoints support both IPv4 and IPv6 connectivity and DNS resolution, but are otherwise functionally equivalent to the existing REST endpoints.

If your permissions and configuration are set up such that the web site endpoint works, then the REST endpoint should work, too.

However... the two endpoints do not offer the same functionality.

Roughly speaking, the REST endpoint is better-suited for machine access and the web site endpoint is better suited for human access, since the web site endpoint offers friendly error messages, index documents, and redirects, while the REST endpoint doesn't. On the other hand, the REST endpoint offers HTTPS and support for signed URLs, while the web site endpoint doesn't.

Choose the correct type of endpoint (REST or web site) for your application:

http://docs.aws.amazon.com/AmazonS3/latest/dev/WebsiteEndpoints.html#WebsiteRestEndpointDiff


¹ s3-external-1.amazonaws.com has been referred to as the "Northern Virginia endpoint," in contrast to the "Global endpoint" s3.amazonaws.com. It was unofficially possible to get read-after-write consistency on new objects in this region if the "s3-external-1" hostname was used, because this would send you to a subset of possible physical endpoints that could provide that functionality. This behavior is now officially supported on this endpoint, so this is probably the better choice in many applications. Previously, s3-external-2 had been referred to as the "Pacific Northwest endpoint" for US-Standard, though it is now a CNAME in DNS for s3-external-1 so s3-external-2 appears to have no purpose except backwards-compatibility.

Uncaught TypeError: Cannot set property 'value' of null

I knew that i am too late for this answer, but i hope this will help to other who are facing and who will face.

As you have written h_url is global var like var = h_url; so you can use that variable anywhere in your file.

  • h_url=document.getElementById("u").value; Here h_url contain value of your search box text value whatever user has typed.

  • document.getElementById("u"); This is the identifier of your form field with some specific ID.

  • Your Search Field without id

    <input type="text" class="searchbox1" name="search" placeholder="Search for Brand, Store or an Item..." value="text" />

  • Alter Search Field with id

    <input id="u" type="text" class="searchbox1" name="search" placeholder="Search for Brand, Store or an Item..." value="text" />

  • When you click on submit that will try to fetch value from document.getElementById("u").value; which is syntactically right but you haven't define id so that will return null.

  • So, Just make sure while you use form fields first define that ID and do other task letter.

I hope this helps you and never get Cannot set property 'value' of null Error.

Regex to remove all special characters from string?

[^a-zA-Z0-9] is a character class matches any non-alphanumeric characters.

Alternatively, [^\w\d] does the same thing.

Usage:

string regExp = "[^\w\d]";
string tmp = Regex.Replace(n, regExp, "");

Binding Combobox Using Dictionary as the Datasource

Use -->

comboBox1.DataSource = colors.ToList();

Unless the dictionary is converted to list, combo-box can't recognize its members.

How add class='active' to html menu with php

Why don't you create a function or class for this navigation and put there active page as a parameter? This way you'd call it as, for example:

$navigation = new Navigation( 1 );

or

$navigation = navigation( 1 );

Requested bean is currently in creation: Is there an unresolvable circular reference?

In general, the most appropriated way to avoid this problem, (also because of better Mockito integration in JUnit) is to use the Setter/Field Injection as described at https://www.baeldung.com/circular-dependencies-in-spring and at https://docs.spring.io/spring/docs/current/spring-framework-reference/html/beans.html

@Component("bean1")
@Scope("view")
public class Bean1 {
    private Bean2 bean2;

    @Autowired
    public void setBean2(Bean2 bean2) {
        this.bean2 = bean2;
    }
}

@Component("bean2")
@Scope("view")
public class Bean2 {
    private Bean1 bean1;

    @Autowired
    public void setBean1(Bean1 bean1) {
        this.bean1 = bean1;
    }
}

Bootstrap table striped: How do I change the stripe background colour?

.table-striped > tbody > tr:nth-child(2n+1) > td, .table-striped > tbody > tr:nth-child(2n+1) > th {
   background-color: red;
}

change this line in bootstrap.css or you could use (odd) or (even) instead of (2n+1)

This could be due to the service endpoint binding not using the HTTP protocol

I had this problem because I configured my WCF Service to return a System.Data.DataTable.

It worked fine in my test HTML page, but blew up when I put this in my Windows Form application.

I had to go in and change the Service's Operational Contract signature from DataTable to DataSet and return the data accordingly.

If you have this problem, you may want to add an additional Operational Contract to your Service so you do not have to worry about breaking code that rely on existing Services.

SQL query to get most recent row for each instance of a given key

Both of the above answers assume that you only have one row for each user and time_stamp. Depending on the application and the granularity of your time_stamp this may not be a valid assumption. If you need to deal with ties of time_stamp for a given user, you'd need to extend one of the answers given above.

To write this in one query would require another nested sub-query - things will start getting more messy and performance may suffer.

I would have loved to have added this as a comment but I don't yet have 50 reputation so sorry for posting as a new answer!

Servlet returns "HTTP Status 404 The requested resource (/servlet) is not available"

An old thread, but since I didn't find it elsewhere, here is one more possibility:

If you're using servlet-api 3.0+, then your web.xml must NOT include metadata-complete="true" attribute

enter image description here

This tells tomcat to map the servlets using data given in web.xml instead of using the @WebServlet annotation.

Overwriting txt file in java

The easiest way to overwrite a text file is to use a public static field.

this will overwrite the file every time because your only using false the first time through.`

public static boolean appendFile;

Use it to allow only one time through the write sequence for the append field of the write code to be false.

// use your field before processing the write code

appendFile = False;

File fnew=new File("../playlist/"+existingPlaylist.getText()+".txt");
String source = textArea.getText();
System.out.println(source);
FileWriter f2;

try {
     //change this line to read this

    // f2 = new FileWriter(fnew,false);

    // to read this
    f2 = new FileWriter(fnew,appendFile); // important part
    f2.write(source);

    // change field back to true so the rest of the new data will
    // append to the new file.

    appendFile = true;

    f2.close();
 } catch (IOException e) {
       // TODO Auto-generated catch block
       e.printStackTrace();
 }           

Insert Multiple Rows Into Temp Table With SQL Server 2012

When using SQLFiddle, make sure that the separator is set to GO. Also the schema build script is executed in a different connection from the run script, so a temp table created in the one is not visible in the other. This fiddle shows that your code is valid and working in SQL 2012:

SQL Fiddle

MS SQL Server 2012 Schema Setup:

Query 1:

CREATE TABLE #Names
  ( 
    Name1 VARCHAR(100),
    Name2 VARCHAR(100)
  ) 

INSERT INTO #Names
  (Name1, Name2)
VALUES
  ('Matt', 'Matthew'),
  ('Matt', 'Marshal'),
  ('Matt', 'Mattison')

SELECT * FROM #NAMES

Results:

| NAME1 |    NAME2 |
--------------------
|  Matt |  Matthew |
|  Matt |  Marshal |
|  Matt | Mattison |

Here a SSMS 2012 screenshot: enter image description here

SQL Server function to return minimum date (January 1, 1753)

Enter the date as a native value 'yyyymmdd' to avoid regional issues:

select cast('17530101' as datetime)

Yes, it would be great if TSQL had MinDate() = '00010101', but no such luck.

Want to make Font Awesome icons clickable

You can wrap those elements in anchor tag

like this

<a href="your link here"> <i class="fa fa-dribbble fa-4x"></i></a>
<a href="your link here"> <i class="fa fa-behance-square fa-4x"></i></a>
<a href="your link here"> <i class="fa fa-linkedin-square fa-4x"></i></a>
<a href="your link here"> <i class="fa fa-twitter-square fa-4x"></i></a>
<a href="your link here"> <i class="fa fa-facebook-square fa-4x"></i></a>

Note: Replace href="your link here" with your desired link e.g. href="https://www.stackoverflow.com".

Call Python script from bash with argument

Beside sys.argv, also take a look at the argparse module, which helps define options and arguments for scripts.

The argparse module makes it easy to write user-friendly command-line interfaces.

How do I auto size a UIScrollView to fit its content

Wrapping Richy's code I created a custom UIScrollView class that automates content resizing completely!

SBScrollView.h

@interface SBScrollView : UIScrollView
@end

SBScrollView.m:

@implementation SBScrollView
- (void) layoutSubviews
{
    CGFloat scrollViewHeight = 0.0f;
    self.showsHorizontalScrollIndicator = NO;
    self.showsVerticalScrollIndicator = NO;
    for (UIView* view in self.subviews)
    {
        if (!view.hidden)
        {
            CGFloat y = view.frame.origin.y;
            CGFloat h = view.frame.size.height;
            if (y + h > scrollViewHeight)
            {
                scrollViewHeight = h + y;
            }
        }
    }
    self.showsHorizontalScrollIndicator = YES;
    self.showsVerticalScrollIndicator = YES;
    [self setContentSize:(CGSizeMake(self.frame.size.width, scrollViewHeight))];
}
@end

How to use:
Simply import the .h file to your view controller and declare a SBScrollView instance instead of the normal UIScrollView one.

How do I set up HttpContent for my HttpClient PostAsync second parameter?

This is answered in some of the answers to Can't find how to use HttpContent as well as in this blog post.

In summary, you can't directly set up an instance of HttpContent because it is an abstract class. You need to use one the classes derived from it depending on your need. Most likely StringContent, which lets you set the string value of the response, the encoding, and the media type in the constructor. See: http://msdn.microsoft.com/en-us/library/system.net.http.stringcontent.aspx

How Spring Security Filter Chain works

Spring security is a filter based framework, it plants a WALL(HttpFireWall) before your application in terms of proxy filters or spring managed beans. Your request has to pass through multiple filters to reach your API.

Sequence of execution in Spring Security

  1. WebAsyncManagerIntegrationFilter Provides integration between the SecurityContext and Spring Web's WebAsyncManager.

  2. SecurityContextPersistenceFilter This filter will only execute once per request, Populates the SecurityContextHolder with information obtained from the configured SecurityContextRepository prior to the request and stores it back in the repository once the request has completed and clearing the context holder.
    Request is checked for existing session. If new request, SecurityContext will be created else if request has session then existing security-context will be obtained from respository.

  3. HeaderWriterFilter Filter implementation to add headers to the current response.

  4. LogoutFilter If request url is /logout(for default configuration) or if request url mathces RequestMatcher configured in LogoutConfigurer then

    • clears security context.
    • invalidates the session
    • deletes all the cookies with cookie names configured in LogoutConfigurer
    • Redirects to default logout success url / or logout success url configured or invokes logoutSuccessHandler configured.
  5. UsernamePasswordAuthenticationFilter

    • For any request url other than loginProcessingUrl this filter will not process further but filter chain just continues.
    • If requested URL is matches(must be HTTP POST) default /login or matches .loginProcessingUrl() configured in FormLoginConfigurer then UsernamePasswordAuthenticationFilter attempts authentication.
    • default login form parameters are username and password, can be overridden by usernameParameter(String), passwordParameter(String).
    • setting .loginPage() overrides defaults
    • While attempting authentication
      • an Authentication object(UsernamePasswordAuthenticationToken or any implementation of Authentication in case of your custom auth filter) is created.
      • and authenticationManager.authenticate(authToken) will be invoked
      • Note that we can configure any number of AuthenticationProvider authenticate method tries all auth providers and checks any of the auth provider supports authToken/authentication object, supporting auth provider will be used for authenticating. and returns Authentication object in case of successful authentication else throws AuthenticationException.
    • If authentication success session will be created and authenticationSuccessHandler will be invoked which redirects to the target url configured(default is /)
    • If authentication failed user becomes un-authenticated user and chain continues.
  6. SecurityContextHolderAwareRequestFilter, if you are using it to install a Spring Security aware HttpServletRequestWrapper into your servlet container

  7. AnonymousAuthenticationFilter Detects if there is no Authentication object in the SecurityContextHolder, if no authentication object found, creates Authentication object (AnonymousAuthenticationToken) with granted authority ROLE_ANONYMOUS. Here AnonymousAuthenticationToken facilitates identifying un-authenticated users subsequent requests.

Debug logs
DEBUG - /app/admin/app-config at position 9 of 12 in additional filter chain; firing Filter: 'AnonymousAuthenticationFilter'
DEBUG - Populated SecurityContextHolder with anonymous token: 'org.springframework.security.authentication.AnonymousAuthenticationToken@aeef7b36: Principal: anonymousUser; Credentials: [PROTECTED]; Authenticated: true; Details: org.springframework.security.web.authentication.WebAuthenticationDetails@b364: RemoteIpAddress: 0:0:0:0:0:0:0:1; SessionId: null; Granted Authorities: ROLE_ANONYMOUS' 
  1. ExceptionTranslationFilter, to catch any Spring Security exceptions so that either an HTTP error response can be returned or an appropriate AuthenticationEntryPoint can be launched

  2. FilterSecurityInterceptor
    There will be FilterSecurityInterceptor which comes almost last in the filter chain which gets Authentication object from SecurityContext and gets granted authorities list(roles granted) and it will make a decision whether to allow this request to reach the requested resource or not, decision is made by matching with the allowed AntMatchers configured in HttpSecurityConfiguration.

Consider the exceptions 401-UnAuthorized and 403-Forbidden. These decisions will be done at the last in the filter chain

  • Un authenticated user trying to access public resource - Allowed
  • Un authenticated user trying to access secured resource - 401-UnAuthorized
  • Authenticated user trying to access restricted resource(restricted for his role) - 403-Forbidden

Note: User Request flows not only in above mentioned filters, but there are others filters too not shown here.(ConcurrentSessionFilter,RequestCacheAwareFilter,SessionManagementFilter ...)
It will be different when you use your custom auth filter instead of UsernamePasswordAuthenticationFilter.
It will be different if you configure JWT auth filter and omit .formLogin() i.e, UsernamePasswordAuthenticationFilter it will become entirely different case.


Just For reference. Filters in spring-web and spring-security
Note: refer package name in pic, as there are some other filters from orm and my custom implemented filter.

enter image description here

From Documentation ordering of filters is given as

  • ChannelProcessingFilter
  • ConcurrentSessionFilter
  • SecurityContextPersistenceFilter
  • LogoutFilter
  • X509AuthenticationFilter
  • AbstractPreAuthenticatedProcessingFilter
  • CasAuthenticationFilter
  • UsernamePasswordAuthenticationFilter
  • ConcurrentSessionFilter
  • OpenIDAuthenticationFilter
  • DefaultLoginPageGeneratingFilter
  • DefaultLogoutPageGeneratingFilter
  • ConcurrentSessionFilter
  • DigestAuthenticationFilter
  • BearerTokenAuthenticationFilter
  • BasicAuthenticationFilter
  • RequestCacheAwareFilter
  • SecurityContextHolderAwareRequestFilter
  • JaasApiIntegrationFilter
  • RememberMeAuthenticationFilter
  • AnonymousAuthenticationFilter
  • SessionManagementFilter
  • ExceptionTranslationFilter
  • FilterSecurityInterceptor
  • SwitchUserFilter

You can also refer
most common way to authenticate a modern web app?
difference between authentication and authorization in context of Spring Security?

Twitter Bootstrap Form File Element Upload Button

With no additional plugin required, this bootstrap solution works great for me:

<div style="position:relative;">
        <a class='btn btn-primary' href='javascript:;'>
            Choose File...
            <input type="file" style='position:absolute;z-index:2;top:0;left:0;filter: alpha(opacity=0);-ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";opacity:0;background-color:transparent;color:transparent;' name="file_source" size="40"  onchange='$("#upload-file-info").html($(this).val());'>
        </a>
        &nbsp;
        <span class='label label-info' id="upload-file-info"></span>
</div>

demo:

http://jsfiddle.net/haisumbhatti/cAXFA/1/ (bootstrap 2)

enter image description here

http://jsfiddle.net/haisumbhatti/y3xyU/ (bootstrap 3)

enter image description here

How to replace all double quotes to single quotes using jquery?

Use double quote to enclose the quote or escape it.

newTemp = mystring.replace(/"/g, "'");

or

newTemp = mystring.replace(/"/g, '\'');

What is the easiest way to encrypt a password when I save it to the registry?

..NET provides cryptographics services in class contained in the System.Security.Cryptography namespace.

How to add a form load event (currently not working)

Three ways you can do this - from the form designer, select the form, and where you normally see the list of properties, just above it there should be a little lightning symbol - this shows you all the events of the form. Find the form load event in the list, and you should be able to pick ProgramViwer_Load from the dropdown.

A second way to do it is programmatically - somewhere (constructor maybe) you'd need to add it, something like: ProgramViwer.Load += new EventHandler(ProgramViwer_Load);

A third way using the designer (probably the quickest) - when you create a new form, double click on the middle of it on it in design mode. It'll create a Form load event for you, hook it in, and take you to the event handler code. Then you can just add your two lines and you're good to go!

How to create a stacked bar chart for my DataFrame using seaborn?

You could use pandas plot as @Bharath suggest:

import seaborn as sns
sns.set()
df.set_index('App').T.plot(kind='bar', stacked=True)

Output:

enter image description here

Updated:

from matplotlib.colors import ListedColormap df.set_index('App')\ .reindex_axis(df.set_index('App').sum().sort_values().index, axis=1)\ .T.plot(kind='bar', stacked=True, colormap=ListedColormap(sns.color_palette("GnBu", 10)), figsize=(12,6))

Updated Pandas 0.21.0+ reindex_axis is deprecated, use reindex

from matplotlib.colors import ListedColormap

df.set_index('App')\
  .reindex(df.set_index('App').sum().sort_values().index, axis=1)\
  .T.plot(kind='bar', stacked=True,
          colormap=ListedColormap(sns.color_palette("GnBu", 10)), 
          figsize=(12,6))

Output:

enter image description here

How can I debug javascript on Android?

I use Weinre, part of Apache Cordova.

With Weinre, I get Google Chrome's debug console in my desktop browser, and can connect Android to that debug console, and debug HTML and CSS. I can execute Javascript commands in the console, and they affect the Web page in the Android browser. Log messages from Android appear in the desktop debug console.

However I think it's not possible to view or step through the actual Javascript code. So I combine Weinre with log messages.

(I don't know much about JConsole but it seems to me that HTML and CSS inspection isn't possible with JConsole, only Javascript commands and logging (?).)

jQuery: Test if checkbox is NOT checked

There are two way you can check condition.

if ($("#checkSurfaceEnvironment-1").is(":checked")) {
    // Put your code here if checkbox is checked
}

OR you can use this one also

if($("#checkSurfaceEnvironment-1").prop('checked') == true){
    // Put your code here if checkbox is checked
}

I hope this is useful for you.

Should a RESTful 'PUT' operation return something

I used RESTful API in my services, and here is my opinion: First we must get to a common view: PUT is used to update an resource not create or get.

I defined resources with: Stateless resource and Stateful resource:

  • Stateless resources For these resources, just return the HttpCode with empty body, it's enough.

  • Stateful resources For example: the resource's version. For this kind of resources, you must provide the version when you want to change it, so return the full resource or return the version to the client, so the client need't to send a get request after the update action.

But, for a service or system, keep it simple, clearly, easy to use and maintain is the most important thing.

jQuery table sort

We just started using this slick tool: https://plugins.jquery.com/tablesorter/

There is a video on its use at: http://www.highoncoding.com/Articles/695_Sorting_GridView_Using_JQuery_TableSorter_Plug_in.aspx

    $('#tableRoster').tablesorter({
        headers: {
            0: { sorter: false },
            4: { sorter: false }
        }
    });

With a simple table

<table id="tableRoster">
        <thead> 
                  <tr>
                    <th><input type="checkbox" class="rCheckBox" value="all" id="rAll" ></th>
                    <th>User</th>
                    <th>Verified</th>
                    <th>Recently Accessed</th>
                    <th>&nbsp;</th>
                  </tr>
        </thead>

Python convert decimal to hex

hex_map = {0:0, 1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8, 9:9, 10:'A', 11:'B', 12:'C', 13:'D', 14:'E', 15:'F'}

def to_hex(n):
    result = ""
    if n == 0:
        return '0'
    while n != 0:
        result += str(hex_map[(n % 16)])
        n = n // 16
    return '0x'+result[::-1]

Getting list of pixel values from PIL

Looks like PILlow may have changed tostring() to tobytes(). When trying to extract RGBA pixels to get them into an OpenGL texture, the following worked for me (within the glTexImage2D call which I omit for brevity).

from PIL import Image
img = Image.open("mandrill.png").rotate(180).transpose(Image.FLIP_LEFT_RIGHT)

# use img.convert("RGBA").tobytes() as texels

Calling Python in Java?

You can call any language from java using Java Native Interface

Bootstrap Collapse not Collapsing

bootstrap.js is using jquery library so you need to add jquery library before bootstrap js.

so please add it jquery library like

Note : Please maintain order of js file. html page use top to bottom approach for compilation

<head>
    <link rel="stylesheet" href="http://netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">
    <script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>
    <script src="http://netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
</head>

ASP.NET: HTTP Error 500.19 – Internal Server Error 0x8007000d

When trying to set up a .NET Core 1.0 website I got this error, and tried everything else I could find with no luck, including checking the web.config file, IIS_IUSRS permissions, IIS URL rewrite module, etc. In the end, I installed DotNetCore.1.0.0-WindowsHosting.exe from this page: https://www.microsoft.com/net/download and it started working right away.

Specific link to download: https://go.microsoft.com/fwlink/?LinkId=817246

What is PHPSESSID?

PHPSESSID reveals you are using PHP. If you don't want this you can easily change the name using the session.name in your php.ini file or using the session_name() function.

SQL Server : login success but "The database [dbName] is not accessible. (ObjectExplorer)"

Really stupid solution but I'll add it here in case anyone gets here from a Google search.

I'd just restarted the SQL service and was getting this error and in my case, just waiting 10 minutes was enough and it was fine again. Seems this is the error you get when it is just starting up.

How to convert a string of bytes into an int?

I was struggling to find a solution for arbitrary length byte sequences that would work under Python 2.x. Finally I wrote this one, it's a bit hacky because it performs a string conversion, but it works.

Function for Python 2.x, arbitrary length

def signedbytes(data):
    """Convert a bytearray into an integer, considering the first bit as
    sign. The data must be big-endian."""
    negative = data[0] & 0x80 > 0

    if negative:
        inverted = bytearray(~d % 256 for d in data)
        return -signedbytes(inverted) - 1

    encoded = str(data).encode('hex')
    return int(encoded, 16)

This function has two requirements:

  • The input data needs to be a bytearray. You may call the function like this:

    s = 'y\xcc\xa6\xbb'
    n = signedbytes(s)
    
  • The data needs to be big-endian. In case you have a little-endian value, you should reverse it first:

    n = signedbytes(s[::-1])
    

Of course, this should be used only if arbitrary length is needed. Otherwise, stick with more standard ways (e.g. struct).

Time in milliseconds in C

A couple of things might affect the results you're seeing:

  1. You're treating clock_t as a floating-point type, I don't think it is.
  2. You might be expecting (1^4) to do something else than compute the bitwise XOR of 1 and 4., i.e. it's 5.
  3. Since the XOR is of constants, it's probably folded by the compiler, meaning it doesn't add a lot of work at runtime.
  4. Since the output is buffered (it's just formatting the string and writing it to memory), it completes very quickly indeed.

You're not specifying how fast your machine is, but it's not unreasonable for this to run very quickly on modern hardware, no.

If you have it, try adding a call to sleep() between the start/stop snapshots. Note that sleep() is POSIX though, not standard C.

How to find longest string in the table column data

For Oracle 11g:

SELECT COL1 
FROM TABLE1 
WHERE length(COL1) = (SELECT max(length(COL1)) FROM TABLE1);

How to download/upload files from/to SharePoint 2013 using CSOM?

Though this is an old post and have many answers, but here I have my version of code to upload the file to sharepoint 2013 using CSOM(c#)

I hope if you are working with downloading and uploading files then you know how to create Clientcontext object and Web object

/* Assuming you have created ClientContext object and Web object*/
string listTitle = "List title where you want your file to upload";
string filePath = "your file physical path";
List oList = web.Lists.GetByTitle(listTitle);
clientContext.Load(oList.RootFolder);//to load the folder where you will upload the file
FileCreationInformation fileInfo = new FileCreationInformation();

fileInfo.Overwrite = true;
fileInfo.Content = System.IO.File.ReadAllBytes(filePath);
fileInfo.Url = fileName;

File fileToUpload = fileCollection.Add(fileInfo);
clientContext.ExecuteQuery();

fileToUpload.CheckIn("your checkin comment", CheckinType.MajorCheckIn);
if (oList.EnableMinorVersions)
{
    fileToUpload.Publish("your publish comment");
    clientContext.ExecuteQuery();
}
if (oList.EnableModeration)
{
     fileToUpload.Approve("your approve comment"); 
}
clientContext.ExecuteQuery();

And here is the code for download

List oList = web.Lists.GetByTitle("ListNameWhereFileExist");
clientContext.Load(oList);
clientContext.Load(oList.RootFolder);
clientContext.Load(oList.RootFolder.Files);
clientContext.ExecuteQuery();
FileCollection fileCollection = oList.RootFolder.Files;
File SP_file = fileCollection.GetByUrl("fileNameToDownloadWithExtension");
clientContext.Load(SP_file);
clientContext.ExecuteQuery();                
var Local_stream = System.IO.File.Open("c:/testing/" + SP_file.Name, System.IO.FileMode.CreateNew);
var fileInformation = File.OpenBinaryDirect(clientContext, SP_file.ServerRelativeUrl);
var Sp_Stream = fileInformation.Stream;
Sp_Stream.CopyTo(Local_stream);

Still there are different ways I believe that can be used to upload and download.

Add views in UIStackView programmatically

UIStackView uses constraints internally to position its arranged subviews. Exactly what constraints are created depends on how the stack view itself is configured. By default, a stack view will create constraints that lay out its arranged subviews in a horizontal line, pinning the leading and trailing views to its own leading and trailing edges. So your code would produce a layout that looks like this:

|[view1][view2]|

The space that is allocated to each subview is determined by a number of factors including the subview's intrinsic content size and it's compression resistance and content hugging priorities. By default, UIView instances don't define an intrinsic content size. This is something that is generally provided by a subclass, such as UILabel or UIButton.

Since the content compression resistance and content hugging priorities of two new UIView instances will be the same, and neither view provides an intrinsic content size, the layout engine must make its best guess as to what size should be allocated to each view. In your case, it is assigning the first view 100% of the available space, and nothing to the second view.

If you modify your code to use UILabel instances instead, you will get better results:

UILabel *label1 = [UILabel new];
label1.text = @"Label 1";
label1.backgroundColor = [UIColor blueColor];

UILabel *label2 = [UILabel new];
label2.text = @"Label 2";
label2.backgroundColor = [UIColor greenColor];

[self.stack1 addArrangedSubview:label1];
[self.stack1 addArrangedSubview:label2];

Note that it is not necessary to explictly create any constraints yourself. This is the main benefit of using UIStackView - it hides the (often ugly) details of constraint management from the developer.

Entityframework Join using join method and lambdas

You can find a few examples here:

// Fill the DataSet.
DataSet ds = new DataSet();
ds.Locale = CultureInfo.InvariantCulture;
FillDataSet(ds);

DataTable contacts = ds.Tables["Contact"];
DataTable orders = ds.Tables["SalesOrderHeader"];

var query =
    contacts.AsEnumerable().Join(orders.AsEnumerable(),
    order => order.Field<Int32>("ContactID"),
    contact => contact.Field<Int32>("ContactID"),
    (contact, order) => new
    {
        ContactID = contact.Field<Int32>("ContactID"),
        SalesOrderID = order.Field<Int32>("SalesOrderID"),
        FirstName = contact.Field<string>("FirstName"),
        Lastname = contact.Field<string>("Lastname"),
        TotalDue = order.Field<decimal>("TotalDue")
    });


foreach (var contact_order in query)
{
    Console.WriteLine("ContactID: {0} "
                    + "SalesOrderID: {1} "
                    + "FirstName: {2} "
                    + "Lastname: {3} "
                    + "TotalDue: {4}",
        contact_order.ContactID,
        contact_order.SalesOrderID,
        contact_order.FirstName,
        contact_order.Lastname,
        contact_order.TotalDue);
}

Or just google for 'linq join method syntax'.

Is it possible to get element from HashMap by its position?

You can try to implement something like that, look at:

Map<String, Integer> map = new LinkedHashMap<String, Integer>();
map.put("juan", 2);
map.put("pedro", 3);
map.put("pablo", 5);
map.put("iphoncio",9)

List<String> indexes = new ArrayList<String>(map.keySet()); // <== Parse

System.out.println(indexes.indexOf("juan"));     // ==> 0
System.out.println(indexes.indexOf("iphoncio"));      // ==> 3

I hope this works for you.

White space showing up on right side of page when background image should extend full length of page

Debug your CSS for Ghost CSS Elements.

Use this bookmark to debug your CSS: https://blog.wernull.com/2013/04/debug-ghost-css-elements-causing-unwanted-scrolling/

Or add the CSS directly yourself:

* {
  background: #000 !important;
  color: #0f0 !important;
  outline: solid #f00 1px !important;
}

In my case a Facebook Like Button caused the problem.

Add property to an array of objects

With ES6 you can simply do:

 for(const element of Results) {
      element.Active = "false";
 }

What is the difference between require and require-dev sections in composer.json?

From the composer site (it's clear enough)

require#

Lists packages required by this package. The package will not be installed unless those requirements can be met.

require-dev (root-only)#

Lists packages required for developing this package, or running tests, etc. The dev requirements of the root package are installed by default. Both install or update support the --no-dev option that prevents dev dependencies from being installed.

Using require-dev in Composer you can declare the dependencies you need for development/testing the project but don't need in production. When you upload the project to your production server (using git) require-dev part would be ignored.

Also check this answer posted by the author and this post as well.

css 100% width div not taking up full width of parent

The problem is caused by your #grid having a width:1140px.

You need to set a min-width:1140px on the body.

This will stop the body from getting smaller than the #grid. Remove width:100% as block level elements take up the available width by default. Live example: http://jsfiddle.net/tw16/LX8R3/

html, body{
    margin:0;
    padding:0;
    min-width: 1140px; /* this is the important part*/
}
#grid-container{
    background:#f8f8f8 url(../images/grid-container-bg.gif) repeat-x top left;
}
#grid{
    width:1140px;
    margin:0px auto;
}

Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.springframework.org/schema/security]

I had the same problem. The only thing that solved it was merge the content of META-INF/spring.handler and META-INF/spring.schemas of each spring jar file into same file names under my META-INF project.

This two threads explain it better:

How to style icon color, size, and shadow of Font Awesome Icons

http://fortawesome.github.io/Font-Awesome/examples/

<i class="icon-thumbs-up icon-3x main-color"></i>

Here I have defined a global style in my CSS where main-color is a class, in my case it is a light blue hue. I find that using inline styles on Icons with Font Awesome works well, esp in the case when you name your colors semantically, i.e. nav-color if you want a separate color for that, etc.

In this example on their website, and how I have written in my example as well, the newest version of Font Awesome has changed the syntax slightly of adjusting the size.Before it used to be:

icon-xxlarge

where now I have to use:

icon-3x

Of course, this all depends on what version of Font Awesome you have installed on your environment. Hope this helps.

Message 'src refspec master does not match any' when pushing commits in Git

In 2020:

If none of the 30+ answers has worked, you probably need to run git push origin main (master has been renamed to main at the time of writing this answer)

Count the number of commits on a Git branch

As the OP references Number of commits on branch in git I want to add that the given answers there also work with any other branch, at least since git version 2.17.1 (and seemingly more reliably than the answer by Peter van der Does):

working correctly:

git checkout current-development-branch
git rev-list --no-merges --count master..
62
git checkout -b testbranch_2
git rev-list --no-merges --count current-development-branch..
0

The last command gives zero commits as expected since I just created the branch. The command before gives me the real number of commits on my development-branch minus the merge-commit(s)

not working correctly:

git checkout current-development-branch
git rev-list --no-merges --count HEAD
361
git checkout -b testbranch_1
git rev-list --no-merges --count HEAD
361

In both cases I get the number of all commits in the development branch and master from which the branches (indirectly) descend.

Java split string to array

Consider this example:

public class StringSplit {
  public static void main(String args[]) throws Exception{
    String testString = "Real|How|To|||";
    System.out.println
       (java.util.Arrays.toString(testString.split("\\|")));
    // output : [Real, How, To]
  }
}

The result does not include the empty strings between the "|" separator. To keep the empty strings :

public class StringSplit {
  public static void main(String args[]) throws Exception{
    String testString = "Real|How|To|||";
    System.out.println
       (java.util.Arrays.toString(testString.split("\\|", -1)));
    // output : [Real, How, To, , , ]
  }
}

For more details go to this website: http://www.rgagnon.com/javadetails/java-0438.html

Where is svn.exe in my machine?

Yes reinstall and select command line to get the svn in Program Files-> Tortoise SVN folder.

How do I execute multiple SQL Statements in Access' Query Editor?

create a macro like this

Option Compare Database

Sub a()

DoCmd.RunSQL "DELETE * from TABLENAME where CONDITIONS"

DoCmd.RunSQL "DELETE * from TABLENAME where CONDITIONS"

End Sub

Git fatal: protocol 'https' is not supported

Copy in plain notepad (git clone https://github.com/./Spoon-Knife.git) and paste it in cmd. now it will work.

Excel 2007: How to display mm:ss format not as a DateTime (e.g. 73:07)?

To make life easier when entering multiple dates/times it is possible to use a custom format to remove the need to enter the colon, and the leading "hour" 0. This however requires a second field for the numerical date to be stored, as the displayed date from the custom format is in base 10.

Displaying a number as a time (no need to enter colons, but no time conversion)

For displaying the times on the sheet, and for entering them without having to type the colon set the cell format to custom and use:

0/:00

Then enter your time. For example, if you wanted to enter 62:30, then you would simply type 6230 and your custom format would visually insert a colon 2 decimal points from the right.

If you only need to display the times, stop here.

Converting number to time

If you need to be able to calculate with the times, you will need to convert them from base 10 into the time format.

This can be done with the following formula (change A2 to the relevant cell reference):

=TIME(0,TRUNC(A2/100),MOD(A2,100))

  • =TIME starts the number to time conversion
  • We don't need hours, so enter 0, at the beginning of the formula, as the format is always hh,mm,ss (to display hours and minutes instead of minutes and seconds, place the 0 at the end of the formula).
  • For the minutes, TRUNC(A2/100), discards the rightmost 2 digits.
  • For the seconds, MOD(A2,100) keeps the rightmost 2 digits and discards everything to the left.

The above formula was found and adapted from this article: PC Mag.com - Easy Date and Time Entry in Excel

Alternatively, you could skip the 0/:00 custom formatting, and just enter your time in a cell to be referenced of the edge of the visible workspace or on another sheet as you would for the custom formatting (ie: 6230 for 62:30)

Then change the display format of the cells with the formula to [m]:ss as @Sean Chessire suggested.

Here is a screen shot to show what I mean.

Excel screen shot showing time conversion formula and custom formatting

how to get session id of socket.io client in Client

On socket.io >=1.0, after the connect event has triggered:

var socket = io('localhost');
var id = socket.io.engine.id

Objective-C : BOOL vs bool

From the definition in objc.h:

#if (TARGET_OS_IPHONE && __LP64__)  ||  TARGET_OS_WATCH
typedef bool BOOL;
#else
typedef signed char BOOL; 
// BOOL is explicitly signed so @encode(BOOL) == "c" rather than "C" 
// even if -funsigned-char is used.
#endif

#define YES ((BOOL)1)
#define NO  ((BOOL)0)

So, yes, you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.

Setting up MySQL and importing dump within Dockerfile

I used docker-entrypoint-initdb.d approach (Thanks to @Kuhess) But in my case I want to create my DB based on some parameters I defined in .env file so I did these

1) First I define .env file something like this in my docker root project directory

MYSQL_DATABASE=my_db_name
MYSQL_USER=user_test
MYSQL_PASSWORD=test
MYSQL_ROOT_PASSWORD=test
MYSQL_PORT=3306

2) Then I define my docker-compose.yml file. So I used the args directive to define my environment variables and I set them from .env file

version: '2'
services:
### MySQL Container
    mysql:
        build:
            context: ./mysql
            args:
                - MYSQL_DATABASE=${MYSQL_DATABASE}
                - MYSQL_USER=${MYSQL_USER}
                - MYSQL_PASSWORD=${MYSQL_PASSWORD}
                - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD}
        ports:
            - "${MYSQL_PORT}:3306"

3) Then I define a mysql folder that includes a Dockerfile. So the Dockerfile is this

FROM mysql:5.7
RUN chown -R mysql:root /var/lib/mysql/

ARG MYSQL_DATABASE
ARG MYSQL_USER
ARG MYSQL_PASSWORD
ARG MYSQL_ROOT_PASSWORD

ENV MYSQL_DATABASE=$MYSQL_DATABASE
ENV MYSQL_USER=$MYSQL_USER
ENV MYSQL_PASSWORD=$MYSQL_PASSWORD
ENV MYSQL_ROOT_PASSWORD=$MYSQL_ROOT_PASSWORD

ADD data.sql /etc/mysql/data.sql
RUN sed -i 's/MYSQL_DATABASE/'$MYSQL_DATABASE'/g' /etc/mysql/data.sql
RUN cp /etc/mysql/data.sql /docker-entrypoint-initdb.d

EXPOSE 3306

4) Now I use mysqldump to dump my db and put the data.sql inside mysql folder

mysqldump -h <server name> -u<user> -p <db name> > data.sql

The file is just a normal sql dump file but I add 2 lines at the beginning so the file would look like this

--
-- Create a database using `MYSQL_DATABASE` placeholder
--
CREATE DATABASE IF NOT EXISTS `MYSQL_DATABASE`;
USE `MYSQL_DATABASE`;

-- Rest of queries
DROP TABLE IF EXISTS `x`;
CREATE TABLE `x` (..)
LOCK TABLES `x` WRITE;
INSERT INTO `x` VALUES ...;
...
...
...

So what happening is that I used "RUN sed -i 's/MYSQL_DATABASE/'$MYSQL_DATABASE'/g' /etc/mysql/data.sql" command to replace the MYSQL_DATABASE placeholder with the name of my DB that I have set it in .env file.

|- docker-compose.yml
|- .env
|- mysql
     |- Dockerfile
     |- data.sql

Now you are ready to build and run your container

How to call function of one php file from another php file and pass parameters to it?

you can write the function in a separate file (say common-functions.php) and include it wherever needed.

function getEmployeeFullName($employeeId) {
// Write code to return full name based on $employeeId
}

You can include common-functions.php in another file as below.

include('common-functions.php');
echo 'Name of first employee is ' . getEmployeeFullName(1);

You can include any number of files to another file. But including comes with a little performance cost. Therefore include only the files which are really required.

Why does AngularJS include an empty option in select?

This worked for me

<select ng-init="basicProfile.casteId" ng-model="basicProfile.casteId" class="form-control">
     <option value="0">Select Caste....</option>
     <option data-ng-repeat="option in formCastes" value="{{option.id}}">{{option.casteName}}</option>
 </select>

How to check null objects in jQuery

Check the jQuery FAQ...

You can use the length property of the jQuery collection returned by your selector:

if ( $('#myDiv').length ){}

Maintaining href "open in new tab" with an onClick handler in React

React + TypeScript inline util method:

const navigateToExternalUrl = (url: string, shouldOpenNewTab: boolean = true) =>
shouldOpenNewTab ? window.open(url, "_blank") : window.location.href = url;

How to read a file from jar in Java?

Just for completeness, there has recently been a question on the Jython mailinglist where one of the answers referred to this thread.

The question was how to call a Python script that is contained in a .jar file from within Jython, the suggested answer is as follows (with "InputStream" as explained in one of the answers above:

PythonInterpreter.execfile(InputStream)

Possible to view PHP code of a website?

By using exploits or on badly configured servers it could be possible to download your PHP source. You could however either obfuscate and/or encrypt your code (using Zend Guard, Ioncube or a similar app) if you want to make sure your source will not be readable (to be accurate, obfuscation by itself could be reversed given enough time/resources, but I haven't found an IonCube or Zend Guard decryptor yet...).

How does the "view" method work in PyTorch?

Let's do some examples, from simpler to more difficult.

  1. The view method returns a tensor with the same data as the self tensor (which means that the returned tensor has the same number of elements), but with a different shape. For example:

    a = torch.arange(1, 17)  # a's shape is (16,)
    
    a.view(4, 4) # output below
      1   2   3   4
      5   6   7   8
      9  10  11  12
     13  14  15  16
    [torch.FloatTensor of size 4x4]
    
    a.view(2, 2, 4) # output below
    (0 ,.,.) = 
    1   2   3   4
    5   6   7   8
    
    (1 ,.,.) = 
     9  10  11  12
    13  14  15  16
    [torch.FloatTensor of size 2x2x4]
    
  2. Assuming that -1 is not one of the parameters, when you multiply them together, the result must be equal to the number of elements in the tensor. If you do: a.view(3, 3), it will raise a RuntimeError because shape (3 x 3) is invalid for input with 16 elements. In other words: 3 x 3 does not equal 16 but 9.

  3. You can use -1 as one of the parameters that you pass to the function, but only once. All that happens is that the method will do the math for you on how to fill that dimension. For example a.view(2, -1, 4) is equivalent to a.view(2, 2, 4). [16 / (2 x 4) = 2]

  4. Notice that the returned tensor shares the same data. If you make a change in the "view" you are changing the original tensor's data:

    b = a.view(4, 4)
    b[0, 2] = 2
    a[2] == 3.0
    False
    
  5. Now, for a more complex use case. The documentation says that each new view dimension must either be a subspace of an original dimension, or only span d, d + 1, ..., d + k that satisfy the following contiguity-like condition that for all i = 0, ..., k - 1, stride[i] = stride[i + 1] x size[i + 1]. Otherwise, contiguous() needs to be called before the tensor can be viewed. For example:

    a = torch.rand(5, 4, 3, 2) # size (5, 4, 3, 2)
    a_t = a.permute(0, 2, 3, 1) # size (5, 3, 2, 4)
    
    # The commented line below will raise a RuntimeError, because one dimension
    # spans across two contiguous subspaces
    # a_t.view(-1, 4)
    
    # instead do:
    a_t.contiguous().view(-1, 4)
    
    # To see why the first one does not work and the second does,
    # compare a.stride() and a_t.stride()
    a.stride() # (24, 6, 2, 1)
    a_t.stride() # (24, 2, 1, 6)
    

    Notice that for a_t, stride[0] != stride[1] x size[1] since 24 != 2 x 3

CSS "and" and "or"

Just in case if any one is stuck like me. After going though the post and some hit and trial this worked for me.

input:not([type="checkbox"])input:not([type="radio"])

INSERT INTO @TABLE EXEC @query with SQL Server 2000

N.B. - this question and answer relate to the 2000 version of SQL Server. In later versions, the restriction on INSERT INTO @table_variable ... EXEC ... were lifted and so it doesn't apply for those later versions.


You'll have to switch to a temp table:

CREATE TABLE #tmp (code varchar(50), mount money)
DECLARE @q nvarchar(4000)
SET @q = 'SELECT coa_code, amount FROM T_Ledger_detail'

INSERT INTO  #tmp (code, mount)
EXEC sp_executesql (@q)

SELECT * from #tmp

From the documentation:

A table variable behaves like a local variable. It has a well-defined scope, which is the function, stored procedure, or batch in which it is declared.

Within its scope, a table variable may be used like a regular table. It may be applied anywhere a table or table expression is used in SELECT, INSERT, UPDATE, and DELETE statements. However, table may not be used in the following statements:

INSERT INTO table_variable EXEC stored_procedure

SELECT select_list INTO table_variable statements.

build maven project with propriatery libraries included

Create a new folder, let's say local-maven-repo at the root of your Maven project.

Just add a local repo iside your <project> of your pom.xml:

<repositories>
    <repository>
        <id>local-maven-repo</id>
        <url>file:///${project.basedir}/local-maven-repo</url>
    </repository>
</repositories>

Then for each external jar you want to install, go at the root of your project and execute:

mvn deploy:deploy-file -DgroupId=[GROUP] -DartifactId=[ARTIFACT] -Dversion=[VERS] -Durl=file:./local-maven-repo/ -DrepositoryId=local-maven-repo -DupdateReleaseInfo=true -Dfile=[FILE_PATH]

(Copied from my reply on a similar question)

How to implement reCaptcha for ASP.NET MVC?

For anybody else looking, here is a decent set of steps. http://forums.asp.net/t/1678976.aspx/1

Don't forget to manually add your key in OnActionExecuting() like I did.

Table scroll with HTML and CSS

Works only in Chrome but it can be adapted to other modern browsers. Table falls back to common table with scroll bar in other brws. Uses CSS3 FLEX property.

http://jsfiddle.net/4SUP8/1/

<table border="1px" class="flexy">
    <caption>Lista Sumnjivih vozila:</caption>
    <thead>
        <tr>
            <td>Opis Sumnje</td>
        <td>Registarski<br>broj vozila</td>
        <td>Datum<br>Vreme</td>
        <td>Brzina<br>(km/h)</td>
        <td>Lokacija</td>
        <td>Status</td>
        <td>Akcija</td>
        </tr>
    </thead>
    <tbody>

        <tr>
        <td>Osumnjicen tranzit</td>
        <td>NS182TP</td>
        <td>23-03-2014 20:48:08</td>
        <td>11.3</td>
        <td>Raskrsnica kod pumpe<br></td>
        <td></td>
        <td>Prikaz</td>
        </tr>
        <tr>

        <tr>
        <td>Osumnjicen tranzit</td>
        <td>NS182TP</td>
        <td>23-03-2014 20:48:08</td>
        <td>11.3</td>
        <td>Raskrsnica kod pumpe<br></td>
        <td></td>
        <td>Prikaz</td>
        </tr>
        <tr>

        <tr>
        <td>Osumnjicen tranzit</td>
        <td>NS182TP</td>
        <td>23-03-2014 20:48:08</td>
        <td>11.3</td>
        <td>Raskrsnica kod pumpe<br></td>
        <td></td>
        <td>Prikaz</td>
        </tr>
        <tr>


        <tr>
        <td>Osumnjicen tranzit</td>
        <td>NS182TP</td>
        <td>23-03-2014 20:48:08</td>
        <td>11.3</td>
        <td>Raskrsnica kod pumpe<br></td>
        <td></td>
        <td>Prikaz</td>
        </tr>

    </tbody>
</table>

Style (CSS 3):

caption {
    display: block;
    line-height: 3em;
    width: 100%;
    -webkit-align-items: stretch;
    border: 1px solid #eee;
}

       .flexy {
            display: block;
            width: 90%;
            border: 1px solid #eee;
            max-height: 320px;
            overflow: auto;
        }

        .flexy thead {
            display: -webkit-flex;
            -webkit-flex-flow: row;
        }

        .flexy thead tr {
            padding-right: 15px;
            display: -webkit-flex;
            width: 100%;
            -webkit-align-items: stretch;
        }

        .flexy tbody {
            display: -webkit-flex;
            height: 100px;
            overflow: auto;
            -webkit-flex-flow: row wrap;
        }
        .flexy tbody tr{
            display: -webkit-flex;
            width: 100%;
        }

        .flexy tr td {
            width: 15%;
        }

SSL Error: CERT_UNTRUSTED while using npm command

You can bypass https using below commands:

npm config set strict-ssl false

or set the registry URL from https or http like below:

npm config set registry="http://registry.npmjs.org/"

However, Personally I believe bypassing https is not the real solution, but we can use it as a workaround.

How to hide a div from code (c#)

u can also try from yours design

    <div <%=If(True = True, "style='display: none;'", "")%> >True</div>
<div <%=If(True = False, "style='display: none;'", "")%> >False</div>
<div <%=If(Session.Item("NameExist") IsNot Nothing, "style='display: none;'", "")%> >NameExist</div>
<div <%=If(Session.Item("NameNotExist") IsNot Nothing, "style='display: none;'", "")%> >NameNotExist</div>

Output html

    <div style='display: none;' > True</div>
<div  >False</div>
<div style='display: none;' >NameExist</div>
<div  >NameNotExist</div>

Tool to generate JSON schema from JSON data

json-schema-generator is a neat Ruby based JSON schema generator. It supports both draft 3 and 4 of the JSON schema. It can be run as a standalone executable, or it can be embedded inside of a Ruby script.

Then you can use json-schema to validate JSON samples against your newly generated schema if you want.

Check for special characters (/*-+_@&$#%) in a string?

You could do it with a bool. I've been learning recently and found I could do it this way. In this example, I'm checking a user's input to the console:

using System;
using System.Linq;

namespace CheckStringContent
{
    class Program
    {
        static void Main(string[] args)
        {
            //Get a password to check
            Console.WriteLine("Please input a Password: ");
            string userPassword = Console.ReadLine();

            //Check the string
            bool symbolCheck = userPassword.Any(p => !char.IsLetterOrDigit(p));

            //Write results to console
            Console.WriteLine($"Symbols are present: {symbolCheck}");     
        }
    }
}

This returns 'True' if special chars (symbolCheck) are present in the string, and 'False' if not present.

AsyncTask Android example

When an asynchronous task is executed, the task goes through four steps:

  1. onPreExecute()
  2. doInBackground(Params...)
  3. onProgressUpdate(Progress...)
  4. onPostExecute(Result)

Below is a demo example:

private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {

    protected Long doInBackground(URL... urls) {
        int count = urls.length;
        long totalSize = 0;
        for (int i = 0; i < count; i++) {
            totalSize += Downloader.downloadFile(urls[i]);
            publishProgress((int) ((i / (float) count) * 100));

            // Escape early if cancel() is called
            if (isCancelled())
                break;
        }
        return totalSize;
    }

    protected void onProgressUpdate(Integer... progress) {
        setProgressPercent(progress[0]);
    }

    protected void onPostExecute(Long result) {
        showDialog("Downloaded " + result + " bytes");
    }
 }

And once you created, a task is executed very simply:

new DownloadFilesTask().execute(url1, url2, url3);

How to get previous page url using jquery

    $(document).ready(function() {
               var referrer =  document.referrer;

               if(referrer.equals("Setting.jsp")){                     
                   function goBack() {  
                        window.history.go();                            
                    }
               }  
                   if(referrer.equals("http://localhost:8080/Ads/Terms.jsp")){                     
                        window.history.forward();
                        function noBack() {
                        window.history.forward(); 
                    }
                   }
    }); 

using this you can avoid load previous page load

SQLite Reset Primary Key Field

If you want to reset every RowId via content provider try this

rowCounter=1;
do {            
            rowId = cursor.getInt(0);
            ContentValues values;
            values = new ContentValues();
            values.put(Table_Health.COLUMN_ID,
                       rowCounter);
            updateData2DB(context, values, rowId);
            rowCounter++;

        while (cursor.moveToNext());

public static void updateData2DB(Context context, ContentValues values, int rowId) {
    Uri uri;
    uri = Uri.parseContentProvider.CONTENT_URI_HEALTH + "/" + rowId);
    context.getContentResolver().update(uri, values, null, null);
}

Microsoft.ACE.OLEDB.12.0 provider is not registered

Basically, if you're on a 64-bit machine, IIS 7 is not (by default) serving 32-bit apps, which the database engine operates on. So here is exactly what you do:

1) ensure that the 2007 database engine is installed, this can be downloaded at: http://www.microsoft.com/downloads/details.aspx?FamilyID=7554F536-8C28-4598-9B72-EF94E038C891&displaylang=en

2) open IIS7 manager, and open the Application Pools area. On the right sidebar, you will see an option that says "Set application pool defaults". Click it, and a window will pop up with the options.

3) the second field down, which says 'Enable 32-bit applications' is probably set to FALSE by default. Simply click where it says 'false' to change it to 'true'.

4) Restart your app pool (you can do this by hitting RECYCLE instead of STOP then START, which will also work).

5) done, and your error message will go away.

Force IE9 to emulate IE8. Possible?

On the client side you can add and remove websites to be displayed in Compatibility View from Compatibility View Settings window of IE:

Tools-> Compatibility View Settings

CSS change button style after click

It is possible to do with CSS only by selecting active and focus pseudo element of the button.

button:active{
    background:olive;
}

button:focus{
    background:olive;
}

See codepen: http://codepen.io/fennefoss/pen/Bpqdqx

You could also write a simple jQuery click function which changes the background color.

HTML:

<button class="js-click">Click me!</button>

CSS:

button {
  background: none;
}

JavaScript:

  $( ".js-click" ).click(function() {
    $( ".js-click" ).css('background', 'green');
  });

Check out this codepen: http://codepen.io/fennefoss/pen/pRxrVG

Using variable in SQL LIKE statement

As Andrew Brower says, but adding a trim

ALTER PROCEDURE <Name>
(
    @PartialName VARCHAR(50) = NULL
)

SELECT Name 
    FROM <table>
    WHERE Name LIKE '%' + LTRIM(RTRIM(@PartialName)) + '%'

"commence before first target. Stop." error

Also, make sure you dont have a space after \ in previous line Else this is the error

Can ordered list produce result that looks like 1.1, 1.2, 1.3 (instead of just 1, 2, 3, ...) with css?

Note: Use CSS counters to create nested numbering in a modern browser. See the accepted answer. The following is for historical interest only.


If the browser supports content and counter,

_x000D_
_x000D_
.foo {_x000D_
  counter-reset: foo;_x000D_
}_x000D_
.foo li {_x000D_
  list-style-type: none;_x000D_
}_x000D_
.foo li::before {_x000D_
  counter-increment: foo;_x000D_
  content: "1." counter(foo) " ";_x000D_
}
_x000D_
<ol class="foo">_x000D_
  <li>uno</li>_x000D_
  <li>dos</li>_x000D_
  <li>tres</li>_x000D_
  <li>cuatro</li>_x000D_
</ol>
_x000D_
_x000D_
_x000D_

Any reason to prefer getClass() over instanceof when generating .equals()?

Both methods have their problems.

If the subclass changes the identity, then you need to compare their actual classes. Otherwise, you violate the symmetric property. For instance, different types of Persons should not be considered equivalent, even if they have the same name.

However, some subclasses don't change identity and these need to use instanceof. For instance, if we have a bunch of immutable Shape objects, then a Rectangle with length and width of 1 should be equal to the unit Square.

In practice, I think the former case is more likely to be true. Usually, subclassing is a fundamental part of your identity and being exactly like your parent except you can do one little thing does not make you equal.

Should I use Python 32bit or Python 64bit

Machine learning packages like tensorflow 2.x are designed to work only on 64 bit Python as they are memory intensive.

Merging Cells in Excel using C#

Using the Interop you get a range of cells and call the .Merge() method on that range.

eWSheet.Range[eWSheet.Cells[1, 1], eWSheet.Cells[4, 1]].Merge();

How to rename uploaded file before saving it into a directory?

The move_uploaded_file will return false if the file was not successfully moved you can put something into your code to alert you in a log if that happens, that should help you figure out why your having trouble renaming the file

groovy: safely find a key in a map and return its value

In general, this depends what your map contains. If it has null values, things can get tricky and containsKey(key) or get(key, default) should be used to detect of the element really exists. In many cases the code can become simpler you can define a default value:

def mymap = [name:"Gromit", likes:"cheese", id:1234]
def x1 = mymap.get('likes', '[nothing specified]')
println "x value: ${x}" }

Note also that containsKey() or get() are much faster than setting up a closure to check the element mymap.find{ it.key == "likes" }. Using closure only makes sense if you really do something more complex in there. You could e.g. do this:

mymap.find{ // "it" is the default parameter
  if (it.key != "likes") return false
  println "x value: ${it.value}" 
  return true // stop searching
}

Or with explicit parameters:

mymap.find{ key,value ->
  (key != "likes")  return false
  println "x value: ${value}" 
  return true // stop searching
}

Declare a variable in DB2 SQL

I imagine this forum posting, which I quote fully below, should answer the question.


Inside a procedure, function, or trigger definition, or in a dynamic SQL statement (embedded in a host program):

BEGIN ATOMIC
 DECLARE example VARCHAR(15) ;
 SET example = 'welcome' ;
 SELECT *
 FROM   tablename
 WHERE  column1 = example ;
END

or (in any environment):

WITH t(example) AS (VALUES('welcome'))
SELECT *
FROM   tablename, t
WHERE  column1 = example

or (although this is probably not what you want, since the variable needs to be created just once, but can be used thereafter by everybody although its content will be private on a per-user basis):

CREATE VARIABLE example VARCHAR(15) ;
SET example = 'welcome' ;
SELECT *
FROM   tablename
WHERE  column1 = example ;

How to force C# .net app to run only one instance in Windows?

another way to single instance an application is to check their hash sums. after messing around with mutex (didn't work as i want) i got it working this way:

    [DllImport("user32.dll")]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool SetForegroundWindow(IntPtr hWnd);

    public Main()
    {
        InitializeComponent();

        Process current = Process.GetCurrentProcess();
        string currentmd5 = md5hash(current.MainModule.FileName);
        Process[] processlist = Process.GetProcesses();
        foreach (Process process in processlist)
        {
            if (process.Id != current.Id)
            {
                try
                {
                    if (currentmd5 == md5hash(process.MainModule.FileName))
                    {
                        SetForegroundWindow(process.MainWindowHandle);
                        Environment.Exit(0);
                    }
                }
                catch (/* your exception */) { /* your exception goes here */ }
            }
        }
    }

    private string md5hash(string file)
    {
        string check;
        using (FileStream FileCheck = File.OpenRead(file))
        {
            MD5 md5 = new MD5CryptoServiceProvider();
            byte[] md5Hash = md5.ComputeHash(FileCheck);
            check = BitConverter.ToString(md5Hash).Replace("-", "").ToLower();
        }

        return check;
    }

it checks only md5 sums by process id.

if an instance of this application was found, it focuses the running application and exit itself.

you can rename it or do what you want with your file. it wont open twice if the md5 hash is the same.

may someone has suggestions to it? i know it is answered, but maybe someone is looking for a mutex alternative.

Javascript Audio Play on click

While several answers are similar, I still had an issue - the user would click the button several times, playing the audio over itself (either it was clicked by accident or they were just 'playing'....)

An easy fix:

var music = new Audio();
function playMusic(file) {
    music.pause();
    music = new Audio(file);
    music.play();
}

Setting up the audio on load allowed 'music' to be paused every time the function is called - effectively stopping the 'noise' even if they user clicks the button several times (and there is also no need to turn off the button, though for user experience it may be something you want to do).

Removing elements with Array.map in JavaScript

I just wrote array intersection that correctly handles also duplicates

https://gist.github.com/gkucmierz/8ee04544fa842411f7553ef66ac2fcf0

_x000D_
_x000D_
// array intersection that correctly handles also duplicates_x000D_
_x000D_
const intersection = (a1, a2) => {_x000D_
  const cnt = new Map();_x000D_
  a2.map(el => cnt[el] = el in cnt ? cnt[el] + 1 : 1);_x000D_
  return a1.filter(el => el in cnt && 0 < cnt[el]--);_x000D_
};_x000D_
_x000D_
const l = console.log;_x000D_
l(intersection('1234'.split``, '3456'.split``)); // [ '3', '4' ]_x000D_
l(intersection('12344'.split``, '3456'.split``)); // [ '3', '4' ]_x000D_
l(intersection('1234'.split``, '33456'.split``)); // [ '3', '4' ]_x000D_
l(intersection('12334'.split``, '33456'.split``)); // [ '3', '3', '4' ]
_x000D_
_x000D_
_x000D_

Position: absolute and parent height?

Here is my workaround,
In your example you can add a third element with "same styles" of .one & .two elements, but without the absolute position and with hidden visibility:

HTML

<article>
   <div class="one"></div>
   <div class="two"></div>
   <div class="three"></div>
</article>

CSS

.three{
    height: 30px;
    z-index: -1;
    visibility: hidden;
}

Is it possible to use a batch file to establish a telnet session, send a command and have the output written to a file?

Maybe something like this ?

Create a batch to connect to telnet and run a script to issue commands ? source

Batch File (named Script.bat ):

     :: Open a Telnet window
   start telnet.exe 192.168.1.1
   :: Run the script 
    cscript SendKeys.vbs 

Command File (named SendKeys.vbs ):

set OBJECT=WScript.CreateObject("WScript.Shell")
WScript.sleep 50 
OBJECT.SendKeys "mylogin{ENTER}" 
WScript.sleep 50 
OBJECT.SendKeys "mypassword{ENTER}"
WScript.sleep 50 
OBJECT.SendKeys " cd /var/tmp{ENTER}" 
WScript.sleep 50 
OBJECT.SendKeys " rm log_web_activity{ENTER}" 
WScript.sleep 50 
OBJECT.SendKeys " ln -s /dev/null log_web_activity{ENTER}" 
WScript.sleep 50 
OBJECT.SendKeys "exit{ENTER}" 
WScript.sleep 50 
OBJECT.SendKeys " "

Getting the screen resolution using PHP

The quick answer is no, then you are probably asking why can't I do that with php. OK here is a longer answer. PHP is a serverside scripting language and therefor has nothing to do with the type of a specific client. Then you might ask "why can I then get the browser agent from php?", thats because that information is sent with the initial HTTP headers upon request to the server. So if you want client information that's not sent with the HTTP header you must you a client scripting language like javascript.

Using "If cell contains #N/A" as a formula condition.

"N/A" is not a string it is an error, try this:

=if(ISNA(A1),C1)

you have to place this fomula in cell B1 so it will get the value of your formula