Programs & Examples On #Sharepoint 2003

Microsoft Sharepoint Version 2003.

Jquery ajax call click event submit button

You did not add # before id of the button. You do not have right selector in your jquery code. So jquery is never execute in your button click. its submitted your form directly not passing any ajax request.

See documentation: http://api.jquery.com/category/selectors/
its your friend.

Try this:

It seems that id: $("#Shareitem").val() is wrong if you want to pass the value of

<input type="hidden" name="id" value="" id="id">

you need to change this line:

id: $("#Shareitem").val()

by

id: $("#id").val()

All together:

 <script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>
    <script>
    $(document).ready(function(){
      $("#Shareitem").click(function(e){
          e.preventDefault();
        $.ajax({type: "POST",
                url: "/imball-reagens/public/shareitem",
                data: { id: $("#Shareitem").val(), access_token: $("#access_token").val() },
                success:function(result){
          $("#sharelink").html(result);
        }});
      });
    });
    </script>

xsd:boolean element type accept "true" but not "True". How can I make it accept it?

You cannot.

According to the XML Schema specification, a boolean is true or false. True is not valid:


  3.2.2.1 Lexical representation
  An instance of a datatype that is defined as ·boolean· can have the 
  following legal literals {true, false, 1, 0}. 

  3.2.2.2 Canonical representation
  The canonical representation for boolean is the set of 
  literals {true, false}. 

If the tool you are using truly validates against the XML Schema standard, then you cannot convince it to accept True for a boolean.

How to get a path to the desktop for current user in C#?

 string filePath = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
 string extension = ".log";
 filePath += @"\Error Log\" + extension;
 if (!Directory.Exists(filePath))
 {
      Directory.CreateDirectory(filePath);
 }

Load dimension value from res/values/dimension.xml from source code

You can write integer in xml file also..
have you seen [this] http://developer.android.com/guide/topics/resources/more-resources.html#Integer ? use as .

 context.getResources().getInteger(R.integer.height_pop);

Connecting to Oracle Database through C#?

Basically in this case, System.Data.OracleClient need access to some of the oracle dll which are not part of .Net. Solutions:

  • Install Oracle Client , and add bin location to Path environment varaible of windows OR
  • Copy oraociicus10.dll (Basic-Lite version) or aociei10.dll (Basic version), oci.dll, orannzsbb10.dll and oraocci10.dll from oracle client installable folder to bin folder of application so that application is able to find required dll

jQuery 1.9 .live() is not a function

.live was removed in 1.9, please see the upgrade guide: http://jquery.com/upgrade-guide/1.9/#live-removed

UTF-8 encoding in JSP page

I used encoding filter which has solved my all encoding problem...

 package com.dina.filter;

    import java.io.IOException;
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;

    /**
     *
     * @author DINANATH
     */
    public class EncodingFilter implements Filter {

        private String encoding = "utf-8";

        public void doFilter(ServletRequest request,ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
            request.setCharacterEncoding(encoding);
    //                response.setContentType("text/html;charset=UTF-8");
                    response.setCharacterEncoding(encoding);
            filterChain.doFilter(request, response);

        }

        public void init(FilterConfig filterConfig) throws ServletException {
            String encodingParam = filterConfig.getInitParameter("encoding");
            if (encodingParam != null) {
                encoding = encodingParam;
            }
        }

        public void destroy() {
            // nothing todo
        }

    }

in web.xml

    <filter>
        <filter-name>EncodingFilter</filter-name>
        <filter-class>
        com.dina.filter.EncodingFilter
        </filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
        <param-name>forceEncoding</param-name>
        <param-value>true</param-value>
    </init-param>
    </filter>
    <filter-mapping>
        <filter-name>EncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

Should ol/ul be inside <p> or outside?

GO here http://validator.w3.org/ upload your html file and it will tell you what is valid and what is not.

What is the difference between "mvn deploy" to a local repo and "mvn install"?

"matt b" has it right, but to be specific, the "install" goal copies your built target to the local repository on your file system; useful for small changes across projects not currently meant for the full group.

The "deploy" goal uploads it to your shared repository for when your work is finished, and then can be shared by other people who require it for their project.

In your case, it seems that "install" is used to make the management of the deployment easier since CI's local repo is the shared repo. If CI was on another box, it would have to use the "deploy" goal.

Ajax success event not working

I tried removing the dataType row and it didn't work for me. I got around the issue by using "complete" instead of "success" as the callback. The success callback still fails in IE, but since my script runs and completes anyway that's all I care about.

$.ajax({
    type: 'POST',
    url: 'somescript.php',
    data: someData,
    complete: function(jqXHR) {
       if(jqXHR.readyState === 4) {
          ... run some code ... 
       }   
    }        
 });

in jQuery 1.5 you can also do it like this.

var ajax = $.ajax({
    type: 'POST',
    url: 'somescript.php',
    data: 'someData'
});
ajax.complete(function(jqXHR){
    if(jqXHR.readyState === 4) {
        ... run some code ... 
    }
});

How to change the background color of the options menu?

The style attribute for the menu background is android:panelFullBackground.

Despite what the documentation says, it needs to be a resource (e.g. @android:color/black or @drawable/my_drawable), it will crash if you use a color value directly.

This will also get rid of the item borders that I was unable to change or remove using primalpop's solution.

As for the text color, I haven't found any way to set it through styles in 2.2 and I'm sure I've tried everything (which is how I discovered the menu background attribute). You would need to use primalpop's solution for that.

How to allocate aligned memory only using the standard library?

You could also try posix_memalign() (on POSIX platforms, of course).

axios post request to send form data

https://www.npmjs.com/package/axios

Its Working

// "content-type": "application/x-www-form-urlencoded", // commit this

import axios from 'axios';

let requestData = {
      username : "[email protected]",
      password: "123456
    };
   
    const url = "Your Url Paste Here";

    let options = {
      method: "POST",
      headers: { 
        'Content-type': 'application/json; charset=UTF-8',

        Authorization: 'Bearer ' + "your token Paste Here",
      },
      data: JSON.stringify(requestData),
      url
    };
    axios(options)
      .then(response => {
        console.log("K_____ res :- ", response);
        console.log("K_____ res status:- ", response.status);
      })
      .catch(error => {
        console.log("K_____ error :- ", error);
      });

fetch request

fetch(url, {
    method: 'POST',
    body: JSON.stringify(requestPayload),           
    headers: {
        'Content-type': 'application/json; charset=UTF-8',
        Authorization: 'Bearer ' + token,
    },
})
    // .then((response) => response.json()) .  // commit out this part if response body is empty
    .then((json) => {
        console.log("response :- ", json);
    }).catch((error)=>{
        console.log("Api call error ", error.message);
        alert(error.message);
});

How to center a subview of UIView

This worked for me

childView.centerXAnchor.constraint(equalTo: parentView.centerXAnchor).isActive = true
childView.centerYAnchor.constraint(equalTo: parentView.centerYAnchor).isActive = true

What is a void pointer in C++?

A void* pointer is used when you want to indicate a pointer to a hunk of memory without specifying the type. C's malloc returns such a pointer, expecting you to cast it to a particular type immediately. It really isn't useful until you cast it to another pointer type. You're expected to know which type to cast it to, the compiler has no reflection capability to know what the underlying type should be.

javascript: pause setTimeout();

You could look into clearTimeout()

or pause depending on a global variable that is set when a certain condition is hit. Like a button is pressed.

  <button onclick="myBool = true" > pauseTimeout </button>

  <script>
  var myBool = false;

  var t = setTimeout(function() {if (!mybool) {dosomething()}}, 5000);
  </script>

How do I install an R package from source?

If you have the file locally, then use install.packages() and set the repos=NULL:

install.packages(path_to_file, repos = NULL, type="source")

Where path_to_file would represent the full path and file name:

  • On Windows it will look something like this: "C:\\RJSONIO_0.2-3.tar.gz".
  • On UNIX it will look like this: "/home/blah/RJSONIO_0.2-3.tar.gz".

Converting HTML to Excel?

Change the content type to ms-excel in the html and browser shall open the html in the Excel as xls. If you want control over the transformation of HTML to excel use POI libraries to do so.

Duplicate and rename Xcode project & associated folders

I using Xcode 6+ and I just do:

  • Copy all files in project folders to new Folders (with new name).
  • Open *.xcodeproj or *.xcworkspace
  • Change name of Project.
  • Click on schema and delete current chema and add new one.

Here is done, but name of window Xcode and *.xcodeproj or *.xcworkspace still <old-name>. Then I do:

  • pop install
  • Open <new name>.xcworkspace

How to check if character is a letter in Javascript?

We can check also in simple way as:

_x000D_
_x000D_
function isLetter(char){_x000D_
    return ( (char >= 'A' &&  char <= 'Z') ||_x000D_
             (char >= 'a' &&  char <= 'z') );_x000D_
}_x000D_
_x000D_
_x000D_
console.log(isLetter("a"));_x000D_
console.log(isLetter(3));_x000D_
console.log(isLetter("H"));
_x000D_
_x000D_
_x000D_

Changing the maximum length of a varchar column?

Using Maria-DB and DB-Navigator tool inside IntelliJ, MODIFY Column worked for me instead of Alter Column

How to start Spyder IDE on Windows

After pip install spyder give this command

pip install --upgrade spyder

This command will update all Spyder dependencies.

Now in command prompt(cmd) navigate to the scripts folder in your python directory. In my system the path is C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts so i use the following command in command prompt.

cd C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts

once you are inside scripts directory type spyder3 and press enter and spyder ide starts.

C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts>spyder3

Difference between JSON.stringify and JSON.parse

var log = { "page": window.location.href, 
        "item": "item", 
        "action": "action" };

log = JSON.stringify(log);
console.log(log);
console.log(JSON.parse(log));

//The output will be:

//For 1st Console is a String Like:

'{ "page": window.location.href,"item": "item","action": "action" }'

//For 2nd Console is a Object Like:

Object {
page   : window.location.href,  
item   : "item",
action : "action" }

Unable to read repository at http://download.eclipse.org/releases/indigo

What worked for me:

Since yesterday, I have been trying to install the Eclipse plugin - "Remote System Explorer" from the Eclipse marketplace on a freshly downloaded Eclipse 4.8 as shown below,

enter image description here

and everytime I was getting this error:

Unable to read repository at http://download.eclipse.org/releases/kepler/. Unable to read repository at http://download.eclipse.org/releases/kepler/201306260900/content.jar. download.eclipse.org:80 failed to respond

which brought me to this SO post.

I tried a few solutions mentioned here in the different answers like this one and this one and this one, but none of them worked. I just gave up almost, thinking that either the corporate network here is somehow blocking the specific download requests or the 4.8 version of Eclipse is buggy.

Discovery:

I could not reload all the paths under 'Window' -> 'Preferences' -> 'Install/Update' -> 'Available Software Sites'.

http reload fails

Preconditions:

  • What did work for me from the beginning was:

    1. I could open google.com from the internal web browser of eclipse and,
    2. some of the update paths, I could reload even. (As was mentioned as a possible solution or test, in some of the answers here, like this one.)

Finally, this answer put me on the right track - for my specific case, at least. Just my step was to do the exact opposite of what that answer was doing.

Solution:

I had to change all the http:\\ paths to https:\\ and suddenly it started to work. I don't know who - either IE/Edge on Windows 10 or the Windows 10 firewall or the company firewall is blocking HTTP communications. But with HTTPS, I can finally install plugins from the Marketplace.

  • HTTPS reload works enter image description here

I must say, what is strange is that not all the paths required https. Except a few, the rest seemed to have had no problem working with HTTP. But I anyways changed all to HTTPS, just for good measure.

enter image description here

  • Then reload all the repositories one by one. Press "Apply and close".
  • Then check for updates. Eclipse will update itself successfully now.
  • Restart after update.
  • Finally you can install whichever Plugin you would like to from the Eclipse Marketplace.

Note: In case during the update, this same error pops up again, then see in the repositories that any new paths added by eclipse during the update, are also HTTPS and not HTTP.

select count(*) from select

You're missing a FROM and you need to give the subquery an alias.

SELECT COUNT(*) FROM 
(
  SELECT DISTINCT a.my_id, a.last_name, a.first_name, b.temp_val
   FROM dbo.Table_A AS a 
   INNER JOIN dbo.Table_B AS b 
   ON a.a_id = b.a_id
) AS subquery;

How can I make my layout scroll both horizontally and vertically?

In this post Scrollview vertical and horizontal in android they talk about a possible solution, quoting:

Matt Clark has built a custom view based on the Android source, and it seems to work perfectly: http://blog.gorges.us/2010/06/android-two-dimensional-scrollview

Beware that the class in that page has a bug calculating the view's horizonal width. A fix by Manuel Hilty is in the comments:

Solution: Replace the statement on line 808 by the following:

final int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(lp.leftMargin + lp.rightMargin, MeasureSpec.UNSPECIFIED);

Most efficient way to see if an ArrayList contains an object in Java

If you need to search many time in the same list, it may pay off to build an index.

Iterate once through, and build a HashMap with the equals value you are looking for as the key and the appropriate node as the value. If you need all instead of anyone of a given equals value, then let the map have a value type of list and build the whole list in the initial iteration.

Please note that you should measure before doing this as the overhead of building the index may overshadow just traversing until the expected node is found.

Succeeded installing but could not start apache 2.4 on my windows 7 system

I have the same problem too, after upgrading win7 to win10. then I check services.msc and found "World Wide Web Publishing Service" was running automatically by default. So then I disabled it, and running the Apache service again.

How to make a rest post call from ReactJS code?

you can install superagent

npm install superagent --save

then for make post call to server

import request from "../../node_modules/superagent/superagent";

request
.post('http://localhost/userLogin')
.set('Content-Type', 'application/x-www-form-urlencoded')
.send({ username: "username", password: "password" })
.end(function(err, res){
console.log(res.text);
});  

UnicodeDecodeError, invalid continuation byte

Use this, If it shows the error of UTF-8

pd.read_csv('File_name.csv',encoding='latin-1')

Dump all documents of Elasticsearch

For your case Elasticdump is the perfect answer.
First, you need to download the mapping and then the index

# Install the elasticdump 
npm install elasticdump -g

# Dump the mapping 
elasticdump --input=http://<your_es_server_ip>:9200/index --output=es_mapping.json --type=mapping

# Dump the data
elasticdump --input=http://<your_es_server_ip>:9200/index --output=es_index.json --type=data    

If you want to dump the data on any server I advise you to install esdump through docker. You can get more info from this website Blog Link

Getting parts of a URL (Regex)

I found the highest voted answer (hometoast's answer) doesn't work perfectly for me. Two problems:

  1. It can not handle port number.
  2. The hash part is broken.

The following is a modified version:

^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:([^\/]*))?((\/\w+)*\/)([\w\-\.]+[^#?\s]+)(\?([^#]*))?(#(.*))?$

Position of parts are as follows:

int SCHEMA = 2, DOMAIN = 3, PORT = 5, PATH = 6, FILE = 8, QUERYSTRING = 9, HASH = 12

Edit posted by anon user:

function getFileName(path) {
    return path.match(/^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:([^\/]*))?((\/[\w\/-]+)*\/)([\w\-\.]+[^#?\s]+)(\?([^#]*))?(#(.*))?$/i)[8];
}

What port is used by Java RMI connection?

If you can modify the client, then have it print out the remote reference and you will see what port it's using. E.g.

ServerApi server = (ServerApi) registry.lookup(ServerApi.RMI_NAME);
System.out.println("Got server handle " + server);

will produce something like:

Got server handle Proxy[ServerApi,RemoteObjectInvocationHandler[UnicastRef [liveRef: [endpoint:172.17.3.190:9001,objID:[-7c63fea8:...

where you can see the port is 9001. If the remote class is not specifying the port, then it will change across reboots. If you want to use a fixed port then you need to make sure the remote class constructor does something like:

super(rmiPort)

How to initialize a nested struct?

You need to redefine the unnamed struct during &Configuration{}

package main

import "fmt"

type Configuration struct {
    Val   string
    Proxy struct {
        Address string
        Port    string
    }
}

func main() {

    c := &Configuration{
        Val: "test",
        Proxy: struct {
            Address string
            Port    string
        }{
            Address: "127.0.0.1",
            Port:    "8080",
        },
    }
    fmt.Println(c)
}

https://play.golang.org/p/Fv5QYylFGAY

How to find the nearest parent of a Git branch?

git parent

You can just run the command

git parent

to find the parent of the branch, if you add the @Joe Chrysler's answer as a git alias. It will simplify the usage.

Open gitconfig file located at "~/.gitconfig" by using any text editor. ( For linux). And for Windows the ".gitconfig" path is generally located at c:\users\your-user\.gitconfig

vim  ~/.gitconfig

Add the following alias command in the file:

[alias]
            parent = "!git show-branch | grep '*' | grep -v \"$(git rev-parse --abbrev-ref HEAD)\" | head -n1 | sed 's/.*\\[\\(.*\\)\\].*/\\1/' | sed 's/[\\^~].*//' #"

Save and exit the editor.

Run the command git parent

That's it!

Access blocked by CORS policy: Response to preflight request doesn't pass access control check

You can just create the required CORS configuration as a bean. As per the code below this will allow all requests coming from any origin. This is good for development but insecure. Spring Docs

@Bean
WebMvcConfigurer corsConfigurer() {
    return new WebMvcConfigurer() {
        @Override
        void addCorsMappings(CorsRegistry registry) {
            registry.addMapping("/**")
                    .allowedOrigins("*")
        }
    }
}

How do I get the parent directory in Python?

>>> import os
>>> os.path.basename(os.path.dirname(<your_path>))

For example in Ubuntu:

>>> my_path = '/home/user/documents'
>>> os.path.basename(os.path.dirname(my_path))
# Output: 'user'

For example in Windows:

>>> my_path = 'C:\WINDOWS\system32'
>>> os.path.basename(os.path.dirname(my_path))
# Output: 'WINDOWS'

Both examples tried in Python 2.7

What is the default root pasword for MySQL 5.7

I just installed Linux Mint 19 (based on Ubuntu 18.04) on my machine. I installed MySQL 5.7 from the repo (sudo apt install mysql-server) and surprisingly during installation, the setup didn't prompt to enter root password. As a result I wasn't able to login into MySQL. I googled here and there and tried various answers I found on the net, including the accepted answer above. I uninstalled (purging all dpkgs with mysql in its name) and reinstalled again from the default Linux Mint repositories. NONE works.

After hours of unproductive works, I decided to reinstall MySQL from the official page. I opened MySQL download page (https://dev.mysql.com/downloads/repo/apt) for apt repo and clicked Download button at the bottom right.

Next, run it with dpkg:

sudo dpkg -i mysql-apt-config_0.8.10-1_all.deb

At the installation setup, choose the MySQL version that you'd like to install. The default option is 8.0 but I changed it to 5.7. Click OK to quit. After this, you have a new MySQL repo in your Software Sources.

Update your repo:

sudo apt update

Finally, install MySQL:

sudo apt install mysql-server

And now I was prompted to provide root password! Hope it helps for others with this same experience.

Checking for empty or null JToken in a JObject

There is also a type - JTokenType.Undefined.

This check must be included in @Brian Rogers answer.

token.Type == JTokenType.Undefined

u'\ufeff' in Python string

I ran into this on Python 3 and found this question (and solution). When opening a file, Python 3 supports the encoding keyword to automatically handle the encoding.

Without it, the BOM is included in the read result:

>>> f = open('file', mode='r')
>>> f.read()
'\ufefftest'

Giving the correct encoding, the BOM is omitted in the result:

>>> f = open('file', mode='r', encoding='utf-8-sig')
>>> f.read()
'test'

Just my 2 cents.

Where does Hive store files in HDFS?

describe formatted <table_name>; inside hive shell.

Notice the "Location" value that shows the location of the table.

how to check if input field is empty

Try this

$.trim($("#spa").val()).length > 0

It will not treat any white space if any as a correct value

C++ Fatal Error LNK1120: 1 unresolved externals

My problem was int Main() instead of int main()

good luck

How often does python flush to a file?

For file operations, Python uses the operating system's default buffering unless you configure it do otherwise. You can specify a buffer size, unbuffered, or line buffered.

For example, the open function takes a buffer size argument.

http://docs.python.org/library/functions.html#open

"The optional buffering argument specifies the file’s desired buffer size:"

  • 0 means unbuffered,
  • 1 means line buffered,
  • any other positive value means use a buffer of (approximately) that size.
  • A negative buffering means to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
  • If omitted, the system default is used.

code:

bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)

Oracle pl-sql escape character (for a " ' ")

SELECT q'[Alex's Tea Factory]' FROM DUAL

Restore a postgres backup file using the command line?

I didnt see here mentions about dump file extension (*.dump).

This solution worked for me:

I got a dump file and needed to recover it.

First I tried to do this with pg_restore and got:

pg_restore: error: input file appears to be a text format dump. Please use psql.

I did it with psql and worked well:

psql -U myUser-d myDataBase < path_to_the_file/file.dump

fatal: does not appear to be a git repository

I met a similar problem when I tried to store my existing repo in my Ubunt One account, I fixed it by the following steps:

Step-1: create remote repo

$ cd ~/Ubuntu\ One/
$ mkdir <project-name>
$ cd <project-name>
$ mkdir .git
$ cd .git
$ git --bare init

Step-2: add the remote

$ git remote add origin /home/<linux-user-name>/Ubuntu\ One/<project-name>/.git

Step-3: push the exising git reop to the remote

$ git push -u origin --all

How to create a DateTime equal to 15 minutes ago?

import datetime and then the magic timedelta stuff:

In [63]: datetime.datetime.now()
Out[63]: datetime.datetime(2010, 12, 27, 14, 39, 19, 700401)

In [64]: datetime.datetime.now() - datetime.timedelta(minutes=15)
Out[64]: datetime.datetime(2010, 12, 27, 14, 24, 21, 684435)

XAMPP permissions on Mac OS X?

What worked for me was,

  • Open Terminal from the XAMPP app,
  • type in this,

chmod -R 0777 /opt/lampp/htdocs/

Curl : connection refused

127.0.0.1 restricts access on every interface on port 8000 except development computer. change it to 0.0.0.0:8000 this will allow connection from curl.

Check if a string is a date value

SimpleDateFormat sdf = new SimpleDateFormat(dateFromat);
sdf.setLenient(false);

By default this is set to TRUE. So even strings of wrong format return good values.

I have used it something like this :

SimpleDateFormat formatter = new SimpleDateFormat("yyyy/MM/dd");
formatter.setLenient(false);
String value = "1990/13/23"; 

try {
      Date date = formatter.parse(value);
      System.out.println(date);
    }catch (ParseException e) 
  {
    System.out.println("its bad");
  }

How to fix "Headers already sent" error in PHP

You do

printf ("Hi %s,</br />", $name);

before setting the cookies, which isn't allowed. You can't send any output before the headers, not even a blank line.

How to reverse a singly linked list using only two pointers?

I have a slightly different approach. I wanted to make use of the existing functions (like insert_at(index), delete_from(index)) to reverse the list (something like a right shift operation). The complexity is still O(n) but the advantage is more reused code. Have a look at another_reverse() method and let me know what you all think.

#include <stdio.h>
#include <stdlib.h>

struct node {
    int data;
    struct node* next;
};

struct node* head = NULL;

void printList(char* msg) {
    struct node* current = head;

    printf("\n%s\n", msg);

    while (current != NULL) {
        printf("%d ", current->data);
        current = current->next;
    }
}

void insert_beginning(int data) {
    struct node* newNode = (struct node*) malloc(sizeof(struct node));

    newNode->data = data;
    newNode->next = NULL;

    if (head == NULL)
    {
        head = newNode;
    } else {
        newNode->next = head;
        head = newNode;
    }
}

void insert_at(int data, int location) {

    struct node* newNode = (struct node*) malloc(sizeof(struct node));

    newNode->data = data;
    newNode->next = NULL;

    if (head == NULL)
    {
        head = newNode;
    }

    else {
        struct node* currentNode = head;
        int index = 0;

        while (currentNode != NULL && index < (location - 1)) {
            currentNode = currentNode->next;
            index++;
        }

        if (currentNode != NULL)
        {
            if (location == 0) {
                newNode->next = currentNode;
                head = newNode;
            } else {
                newNode->next = currentNode->next;
                currentNode->next = newNode;
            }
        }
    }
}


int delete_from(int location) {

    int retValue = -1;

    if (location < 0 || head == NULL)
    {
        printf("\nList is empty or invalid index");
        return -1;
    } else {

        struct node* currentNode = head;
        int index = 0;

        while (currentNode != NULL && index < (location - 1)) {
            currentNode = currentNode->next;
            index++;
        }

        if (currentNode != NULL)
        {
            // we've reached the node just one prior to the one we want to delete

            if (location == 0) {

                if (currentNode->next == NULL)
                {
                    // this is the only node in the list
                    retValue = currentNode->data;
                    free(currentNode);
                    head = NULL;
                } else {

                    // the next node should take its place
                    struct node* nextNode = currentNode->next;
                    head = nextNode;
                    retValue = currentNode->data;
                    free(currentNode);
                }
            } // if (location == 0)
            else {
                // the next node should take its place
                struct node* nextNode = currentNode->next;
                currentNode->next = nextNode->next;

                if (nextNode != NULL
                ) {
                    retValue = nextNode->data;
                    free(nextNode);
                }
            }

        } else {
            printf("\nInvalid index");
            return -1;
        }
    }

    return retValue;
}

void another_reverse() {
    if (head == NULL)
    {
        printf("\nList is empty\n");
        return;
    } else {
        // get the tail pointer

        struct node* tailNode = head;
        int index = 0, counter = 0;

        while (tailNode->next != NULL) {
            tailNode = tailNode->next;
            index++;
        }

        // now tailNode points to the last node
        while (counter != index) {
            int data = delete_from(index);
            insert_at(data, counter);
            counter++;
        }
    }
}

int main(int argc, char** argv) {

    insert_beginning(4);
    insert_beginning(3);
    insert_beginning(2);
    insert_beginning(1);
    insert_beginning(0);

    /*  insert_at(5, 0);
     insert_at(4, 1);
     insert_at(3, 2);
     insert_at(1, 1);*/

    printList("Original List\0");

    //reverse_list();
    another_reverse();

    printList("Reversed List\0");

    /*  delete_from(2);
     delete_from(2);*/

    //printList();
    return 0;
}

Compare two files line by line and generate the difference in another file

You could use diff with following output formatting:

diff --old-line-format='' --unchanged-line-format='' file1 file2

--old-line-format='' , disable output for file1 if line was differ compare in file2.
--unchanged-line-format='', disable output if lines were same.

Change hash without reload in jQuery

The accepted answer didn't work for me as my page jumped slightly on click, messing up my scroll animation.

I decided to update the entire URL using window.history.replaceState rather than using the window.location.hash method. Thus circumventing the hashChange event fired by the browser.

// Only fire when URL has anchor
$('a[href*="#"]:not([href="#"])').on('click', function(event) {

    // Prevent default anchor handling (which causes the page-jumping)
    event.preventDefault();

    if ( location.pathname.replace(/^\//,'') == this.pathname.replace(/^\//,'') && location.hostname == this.hostname ) {
        var target = $(this.hash);
        target = target.length ? target : $('[name=' + this.hash.slice(1) +']');

        if ( target.length ) {    
            // Smooth scrolling to anchor
            $('html, body').animate({
                scrollTop: target.offset().top
            }, 1000);

            // Update URL
            window.history.replaceState("", document.title, window.location.href.replace(location.hash, "") + this.hash);
        }
    }
});

ERROR 2003 (HY000): Can't connect to MySQL server on localhost (10061)

Hey this is not a big issue what you need to do is.....

1. Run your cmd as administrator.

2.What you will see is like this
c:\windows\system32>

3.Go to your bin location by using cd..
like C:\mysql\bin(my location of bin in my computer is what you are seeing so chose yours correctly)

4.C:\mysql\bin>mysql --install
  Service successfully installed.

5.C:\mysql\bin>NET START MySql
 The MySql service is starting
 The MySql service was started successfully

Then last step is

6.C:\mysql\bin>mysql -u root - p admin
It will ask for password don't enter anything first time because it will use blank, n just press enter you are done.

N later you can set password too...:)

How to download the latest artifact from Artifactory repository?

With awk:

     curl  -sS http://the_repo/com/stackoverflow/the_artifact/maven-metadata.xml | grep latest | awk -F'<latest>' '{print $2}' | awk -F'</latest>' '{print $1}'

With sed:

    curl  -sS http://the_repo/com/stackoverflow/the_artifact/maven-metadata.xml | grep latest | sed 's:<latest>::' | sed 's:</latest>::'

cast a List to a Collection

Casting never needs a new:

Collection<T> collection = myList;

You don't even make the cast explicit, because Collection is a super-type of List, so it will work just like this.

Magento How to debug blank white screen

I too had the same problem, but solved after disabling the compiler and again reinstalling the extension. Disable of the compiler can be done by system-> configration-> tools-> compilation.. Here Disable the process... Good Luck

How to overcome root domain CNAME restrictions?

Thanks to both sipwiz and MrEvil. We developed a PHP script that will parse the URL that the user enters and paste www to the top of it. (e.g. if the customer enters kiragiannis.com, then it will redirect to www.kiragiannis.com). So our customer point their root (e.g. customer1.com to A record where our web redirector is) and then www CNAME to the real A record managed by us.

Below the code in case you are interested for future us.

<?php
$url = strtolower($_SERVER["HTTP_HOST"]);

if(strpos($url, "//") !== false) { // remove http://
  $url = substr($url, strpos($url, "//") + 2);
}

$urlPagePath = "";
if(strpos($url, "/") !== false) { // store post-domain page path to append later
  $urlPagePath = substr($url, strpos($url, "/"));
  $url = substr($url, 0, strpos($url,"/"));
}


$urlLast = substr($url, strrpos($url, "."));
$url = substr($url, 0, strrpos($url, "."));


if(strpos($url, ".") !== false) { // get rid of subdomain(s)
  $url = substr($url, strrpos($url, ".") + 1);
}


$url = "http://www." . $url . $urlLast . $urlPagePath;

header( "Location:{$url}");
?>

Will Google Android ever support .NET?

Yes, it will be possible and it won't be that difficult. All what's needed at this point to start with is some kind of converter that will turn MSIL into Dalvik bytecode. Since both formats are open-sourced and well documented, there won't be any problem with it.

So, writing Android applications in C# or VB.NET will be possible, question is how much of .NET framework standard libraries will be supported. But that's another issue.

Oscar Reyes wrote:

I'm pretty sure if google hand ANY interest in .net, they would've design something while Android was in the first stages, not now when they are in production stages. I don't mean it is not possible, what I'm saying is they're not interested. Maybe in mmm hhhh 10 yrs.

Actually what they've already designed is very compatible with Java and .NET

They can't do everything at once, but if you look into Android SDK, there is a tool called dx. This tool converts Java bytecode into Dalvik bytecode, so in other words, you can run programs written in Java on Android with no effort today. Now the same tool is needed for .NET.

Considering how similar .NET and Java are, it's really a matter of time.

ddimitrov wrote:

The .Net->Java->Dalvik translation can be done even now (http://dev.mainsoft.com/), but I think you underestimate the lack of .Net libraries. Of course somebody can port Mono, but it's definitely a non-trivial effort.

No need to port Mono. Android already has VM and some basic API. All what's needed is CIL->Dalvik converter and tiny .NET wrapper for Android API (and maybe some basic implementation of some standard .NET classes). That's it.

Update: .NET already works on Android - you will need product called Monodroid (http://monodroid.net) as stated above.

How to hide elements without having them take space on the page?

Try setting display:none to hide and set display:block to show.

Sending a JSON HTTP POST request from Android

Posting parameters Using POST:-

URL url;
URLConnection urlConn;
DataOutputStream printout;
DataInputStream  input;
url = new URL (getCodeBase().toString() + "env.tcgi");
urlConn = url.openConnection();
urlConn.setDoInput (true);
urlConn.setDoOutput (true);
urlConn.setUseCaches (false);
urlConn.setRequestProperty("Content-Type","application/json");   
urlConn.setRequestProperty("Host", "android.schoolportal.gr");
urlConn.connect();  
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

The part which you missed is in the the following... i.e., as follows..

// Send POST output.
printout = new DataOutputStream(urlConn.getOutputStream ());
printout.writeBytes(URLEncoder.encode(jsonParam.toString(),"UTF-8"));
printout.flush ();
printout.close ();

The rest of the thing you can do it.

Java Equivalent of C# async/await?

There is no equivalent of C# async/await in Java at the language level. A concept known as Fibers aka cooperative threads aka lightweight threads could be an interesting alternative. You can find Java libraries providing support for fibers.

Java libraries implementing Fibers

You can read this article (from Quasar) for a nice introduction to fibers. It covers what threads are, how fibers can be implemented on the JVM and has some Quasar specific code.

enabling cross-origin resource sharing on IIS7

One thing that has not been mentioned in these answers is that if you are using IIS and have sub applications with their own separate web.config, you may need to have a web.config in the parent directory containing the following code.

<httpProtocol>
  <customHeaders>
    <add name="Access-Control-Allow-Origin" value="*"/>
    <add name="Access-Control-Allow-Headers" value="Content-Type"/>
    <add name="Access-Control-Allow-Methods" value="POST,GET,OPTIONS"/>
  </customHeaders>
</httpProtocol>

Import txt file and having each line as a list

lines=[]
with open('file') as file:
   lines.append(file.readline())

Tick symbol in HTML/XHTML

Coming very late to the party, I found that &check; (✓) worked in Opera. I haven't tested it on any other browsers, but it might be useful for some people.

Inverse dictionary lookup in Python

I know this might be considered 'wasteful', but in this scenario I often store the key as an additional column in the value record:

d = {'key1' : ('key1', val, val...), 'key2' : ('key2', val, val...) }

it's a tradeoff and feels wrong, but it's simple and works and of course depends on values being tuples rather than simple values.

How to copy a string of std::string type in C++?

Caesar's solution is the best in my opinion, but if you still insist to use the strcpy function, then after you have your strings ready:

string a = "text";
string b = "image";

You can try either:

strcpy(a.data(), b.data());

or

strcpy(a.c_str(), b.c_str());

Just call either the data() or c_str() member functions of the std::string class, to get the char* pointer of the string object.

The strcpy() function doesn't have overload to accept two std::string objects as parameters. It has only one overload to accept two char* pointers as parameters.

Both data and c_str return what does strcpy() want exactly.

How to get first character of string?

var str="stack overflow";

firstChar  = str.charAt(0);

secondChar = str.charAt(1);

Tested in IE6+, FF, Chrome, safari.

How to start mongodb shell?

bat command to start mongodb

create one folder for database like in this example r0

start /d "{path}\bin" mongod.exe --replSet foo --port 27017 --dbpath {path}mongoDataBase\r0

start /d "{path}\bin" mongo.exe 127.0.0.1:27017

How can I get LINQ to return the object which has the max value for a given property?

In LINQ you can solve it the following way:

Item itemMax = (from i in items
     let maxId = items.Max(m => m.ID)
     where i.ID == maxId
     select i).FirstOrDefault();

How to send 100,000 emails weekly?

Short answer: While it's technically possible to send 100k e-mails each week yourself, the simplest, easiest and cheapest solution is to outsource this to one of the companies that specialize in it (I did say "cheapest": there's no limit to the amount of development time (and therefore money) that you can sink into this when trying to DIY).

Long answer: If you decide that you absolutely want to do this yourself, prepare for a world of hurt (after all, this is e-mail/e-fail we're talking about). You'll need:

  • e-mail content that is not spam (otherwise you'll run into additional major roadblocks on every step, even legal repercussions)
  • in addition, your content should be easy to distinguish from spam - that may be a bit hard to do in some cases (I heard that a certain pharmaceutical company had to all but abandon e-mail, as their brand names are quite common in spams)
  • a configurable SMTP server of your own, one which won't buckle when you dump 100k e-mails onto it (your ISP's upstream server won't be sufficient here and you'll make the ISP violently unhappy; we used two dedicated boxes)
  • some mail wrapper (e.g. PhpMailer if PHP's your poison of choice; using PHP's mail() is horrible enough by itself)
  • your own sender function to run in a loop, create the mails and pass them to the wrapper (note that you may run into PHP's memory limits if your app has a memory leak; you may need to recycle the sending process periodically, or even better, decouple the "creating e-mails" and "sending e-mails" altogether)

Surprisingly, that was the easy part. The hard part is actually sending it:

  • some servers will ban you when you send too many mails close together, so you need to shuffle and watch your queue (e.g. send one mail to [email protected], then three to other domains, only then another to [email protected])
  • you need to have correct PTR, SPF, DKIM records
  • handling remote server timeouts, misconfigured DNS records and other network pleasantries
  • handling invalid e-mails (and no, regex is the wrong tool for that)
  • handling unsubscriptions (many legitimate newsletters have been reclassified as spam due to many frustrated users who couldn't unsubscribe in one step and instead chose to "mark as spam" - the spam filters do learn, esp. with large e-mail providers)
  • handling bounces and rejects ("no such mailbox [email protected]","mailbox [email protected] full")
  • handling blacklisting and removal from blacklists (Sure, you're not sending spam. Some recipients won't be so sure - with such large list, it will happen sometimes, no matter what precautions you take. Some people (e.g. your not-so-scrupulous competitors) might even go as far to falsely report your mailings as spam - it does happen. On average, it takes weeks to get yourself removed from a blacklist.)

And to top it off, you'll have to manage the legal part of it (various federal, state, and local laws; and even different tangles of laws once you send outside the U.S. (note: you have no way of finding if [email protected] lives in Southwest Elbonia, the country with world's most draconian antispam laws)).

I'm pretty sure I missed a few heads of this hydra - are you still sure you want to do this yourself? If so, there'll be another wave, this time merely the annoying problems inherent in sending an e-mail. (You see, SMTP is a store-and-forward protocol, which means that your e-mail will be shuffled across many SMTP servers around the Internet, in the hope that the next one is a bit closer to the final recipient. Basically, the e-mail is sent to an SMTP server, which puts it into its forward queue; when time comes, it will forward it further to a different SMTP server, until it reaches the SMTP server for the given domain. This forward could happen immediately, or in a few minutes, or hours, or days, or never.) Thus, you'll see the following issues - most of which could happen en route as well as at the destination:

  • the remote SMTP servers don't want to talk to your SMTP server
  • your mails are getting marked as spam (<blink> is not your friend here, nor is <font color=...>)
  • your mails are delivered days, even weeks late (contrary to popular opinion, SMTP is designed to make a best effort to deliver the message sometime in the future - not to deliver it now)
  • your mails are not delivered at all (already sent from e-mail server on hop #4, not sent yet from server on hop #5, the server that currently holds the message crashes, data is lost)
  • your mails are mangled by some braindead server en route (this one is somewhat solvable with base64 encoding, but then the size goes up and the e-mail looks more suspicious)
  • your mails are delivered and the recipients seem not to want them ("I'm sure I didn't sign up for this, I remember exactly what I did a year ago" (of course you do, sir))
  • users with various versions of Microsoft Outlook and its special handling of Internet mail
  • wizard's apprentice mode (a self-reinforcing positive feedback loop - in other words, automated e-mails as replies to automated e-mails as replies to...; you really don't want to be the one to set this off, as you'd anger half the internet at yourself)

and it'll be your job to troubleshoot and solve this (hint: you can't, mostly). The people who run a legit mass-mailing businesses know that in the end you can't solve it, and that they can't solve it either - and they have the reasons well researched, documented and outlined (maybe even as a Powerpoint presentation - complete with sounds and cool transitions - that your bosses can understand), as they've had to explain this a million times before. Plus, for the problems that are actually solvable, they know very well how to solve them.

If, after all this, you are not discouraged and still want to do this, go right ahead: it's even possible that you'll find a better way to do this. Just know that the road ahead won't be easy - sending e-mail is trivial, getting it delivered is hard.

Virtual/pure virtual explained

From Wikipedia's Virtual function ...

In object-oriented programming, in languages such as C++, and Object Pascal, a virtual function or virtual method is an inheritable and overridable function or method for which dynamic dispatch is facilitated. This concept is an important part of the (runtime) polymorphism portion of object-oriented programming (OOP). In short, a virtual function defines a target function to be executed, but the target might not be known at compile time.

Unlike a non-virtual function, when a virtual function is overridden the most-derived version is used at all levels of the class hierarchy, rather than just the level at which it was created. Therefore if one method of the base class calls a virtual method, the version defined in the derived class will be used instead of the version defined in the base class.

This is in contrast to non-virtual functions, which can still be overridden in a derived class, but the "new" version will only be used by the derived class and below, but will not change the functionality of the base class at all.

whereas..

A pure virtual function or pure virtual method is a virtual function that is required to be implemented by a derived class if the derived class is not abstract.

When a pure virtual method exists, the class is "abstract" and can not be instantiated on its own. Instead, a derived class that implements the pure-virtual method(s) must be used. A pure-virtual isn't defined in the base-class at all, so a derived class must define it, or that derived class is also abstract, and can not be instantiated. Only a class that has no abstract methods can be instantiated.

A virtual provides a way to override the functionality of the base class, and a pure-virtual requires it.

Corrupt jar file

This will happen when you doubleclick a JAR file in Windows explorer, but the JAR is by itself actually not an executable JAR. A real executable JAR should have at least a class with a main() method and have it referenced in MANIFEST.MF.

In Eclispe, you need to export the project as Runnable JAR file instead of as JAR file to get a real executable JAR.

Or, if your JAR is solely a container of a bunch of closely related classes (a library), then you shouldn't doubleclick it, but open it using some ZIP tool. Windows explorer namely by default associates JAR files with java.exe, which won't work for those kind of libary JARs.

Get element from within an iFrame

None of the other answers were working for me. I ended up creating a function within my iframe that returns the object I was looking for:

function getElementWithinIframe() {
    return document.getElementById('copy-sheet-form');
}

Then you call that function like so to retrieve the element:

var el = document.getElementById("iframeId").contentWindow.functionNameToCall();

How do I strip all spaces out of a string in PHP?

str_replace will do the trick thusly

$new_str = str_replace(' ', '', $old_str);

fatal: Not a valid object name: 'master'

First off, when you create a "bare repository", you're not going to be doing any work with it (it doesn't contain a working copy, so the git branch command is not useful).

Now, the reason you wouldn't have a master branch even after doing a git init is that there are no commits: when you create your first commit, you will then have a master branch.

An exception of type 'System.NullReferenceException' occurred in myproject.DLL but was not handled in user code

It means you have a null reference somewhere in there. Can you debug the app and stop the debugger when it gets here and investigate? Probably img1 is null or ConfigurationManager.AppSettings.Get("Url") is returning null.

Return first N key:value pairs from dict

Dictionary maintains no order , so before picking top N key value pairs lets make it sorted.

import operator
d = {'a': 3, 'b': 2, 'c': 3, 'd': 4}
d=dict(sorted(d.items(),key=operator.itemgetter(1),reverse=True))
#itemgetter(0)=sort by keys, itemgetter(1)=sort by values

Now we can do the retrieval of top 'N' elements:, using the method structure like this:

def return_top(elements,dictionary_element):
    '''Takes the dictionary and the 'N' elements needed in return
    '''
    topers={}
    for h,i in enumerate(dictionary_element):
        if h<elements:
            topers.update({i:dictionary_element[i]})
    return topers

to get the top 2 elements then simply use this structure:

d = {'a': 3, 'b': 2, 'c': 3, 'd': 4}
d=dict(sorted(d.items(),key=operator.itemgetter(1),reverse=True))
d=return_top(2,d)
print(d)

Getting Textarea Value with jQuery

you have id="#message"... should be id="message"

http://jsfiddle.net/q5EXG/1/

Browser Caching of CSS files

Unless you've messed with your server, yes it's cached. All the browsers are supposed to handle it the same. Some people (like me) might have their browsers configured so that it doesn't cache any files though. Closing the browser doesn't invalidate the file in the cache. Changing the file on the server should cause a refresh of the file however.

SQL command to display history of queries

You can look at the query cache: http://www.databasejournal.com/features/mysql/article.php/3110171/MySQLs-Query-Cache.htm but it might not give you access to the actual queries and will be very hit-and-miss if it did work (subtle pun intended)

But MySQL Query Browser very likely maintains its own list of queries that it runs, outside of the MySQL engine. You would have to do the same in your app.

Edit: see dan m's comment leading to this: How to show the last queries executed on MySQL? looks sound.

How do I determine the current operating system with Node.js

You are looking for the OS native module for Node.js:

v4: https://nodejs.org/dist/latest-v4.x/docs/api/os.html#os_os_platform

or v5 : https://nodejs.org/dist/latest-v5.x/docs/api/os.html#os_os_platform

os.platform()

Returns the operating system platform. Possible values are 'darwin', 'freebsd', 'linux', 'sunos' or 'win32'. Returns the value of process.platform.

Is it a good idea to index datetime field in mysql?

Here author performed tests showed that integer unix timestamp is better than DateTime. Note, he used MySql. But I feel no matter what DB engine you use comparing integers are slightly faster than comparing dates so int index is better than DateTime index. Take T1 - time of comparing 2 dates, T2 - time of comparing 2 integers. Search on indexed field takes approximately O(log(rows)) time because index based on some balanced tree - it may be different for different DB engines but anyway Log(rows) is common estimation. (if you not use bitmask or r-tree based index). So difference is (T2-T1)*Log(rows) - may play role if you perform your query oftenly.

"The page has expired due to inactivity" - Laravel 5.5

If you're coming to this answer directly from a search, make sure you have already added the csrf token to your form with {{ csrf_field() }} like the OP.


If you have your session driver set to file:

May have something to do with the storage_path not being writable. This is where it stores session data regarding tokens if you're using file based sessions. The can be verified with is_writable(config('session.files'))


For the OP, the session driver was set to array. Array is for testing only. Since data is not persisted, it will not be able to compare the token on the next request.

The array driver is used during testing and prevents the data stored in the session from being persisted.

https://laravel.com/docs/5.5/session#configuration


Check config/session.php

Lastly, an issue I just had, we had a project which has the session domain and secure settings in config/session.php but the development site was not using HTTPS (SSL/TLS). This caused this generic error since sessions.secure was set to true by default.

Using a dispatch_once singleton model in Swift

Looking at Apple's sample code I came across this pattern. I'm not sure how Swift deals with statics, but this would be thread safe in C#. I include both the property and method for Objective-C interop.

struct StaticRank {
    static let shared = RankMapping()
}

class func sharedInstance() -> RankMapping {
    return StaticRank.shared
}

class var shared:RankMapping {
    return StaticRank.shared
}

How to use querySelectorAll only for elements that have a specific attribute set?

With your example:

<input type="checkbox" id="c2" name="c2" value="DE039230952"/>

Replace $$ with document.querySelectorAll in the examples:

$$('input') //Every input
$$('[id]') //Every element with id
$$('[id="c2"]') //Every element with id="c2"
$$('input,[id]') //Every input + every element with id
$$('input[id]') //Every input including id
$$('input[id="c2"]') //Every input including id="c2"
$$('input#c2') //Every input including id="c2" (same as above)
$$('input#c2[value="DE039230952"]') //Every input including id="c2" and value="DE039230952"
$$('input#c2[value^="DE039"]') //Every input including id="c2" and value has content starting with DE039
$$('input#c2[value$="0952"]') //Every input including id="c2" and value has content ending with 0952
$$('input#c2[value*="39230"]') //Every input including id="c2" and value has content including 39230

Use the examples directly with:

const $$ = document.querySelectorAll.bind(document);

Some additions:

$$(.) //The same as $([class])
$$(div > input) //div is parent tag to input
document.querySelector() //equals to $$()[0] or $()

Faking an RS232 Serial Port

There's always the hardware route. Purchase two USB to serial converters, and connect them via a NULL modem.

Pro tips: 1) Windows may assign new COM ports to the adapters after every device sleep or reboot. 2) The market leaders in chips for USB to serial are Prolific and FTDI. Both companies are battling knockoffs, and may be blocked in future official Windows drivers. The Linux drivers however work fine with the clones.

Running Selenium WebDriver python bindings in chrome

You need to make sure the standalone ChromeDriver binary (which is different than the Chrome browser binary) is either in your path or available in the webdriver.chrome.driver environment variable.

see http://code.google.com/p/selenium/wiki/ChromeDriver for full information on how wire things up.

Edit:

Right, seems to be a bug in the Python bindings wrt reading the chromedriver binary from the path or the environment variable. Seems if chromedriver is not in your path you have to pass it in as an argument to the constructor.

import os
from selenium import webdriver

chromedriver = "/Users/adam/Downloads/chromedriver"
os.environ["webdriver.chrome.driver"] = chromedriver
driver = webdriver.Chrome(chromedriver)
driver.get("http://stackoverflow.com")
driver.quit()

Swift 3 URLSession.shared() Ambiguous reference to member 'dataTask(with:completionHandler:) error (bug)

To load data via a GET request you don't need any URLRequest (and no semicolons)

let listUrlString =  "http://bla.com?batchSize=" + String(batchSize) + "&fromIndex=" + String(fromIndex)
let myUrl = URL(string: listUrlString)!
let task = URLSession.shared.dataTask(with: myUrl) { ...

Why should Java 8's Optional not be used in arguments

One more approach, what you can do is

// get your optionals first
Optional<String> p1 = otherObject.getP1();
Optional<BigInteger> p2 = otherObject.getP2();

// bind values to a function
Supplier<Integer> calculatedValueSupplier = () -> { // your logic here using both optional as state}

Once you have built a function(supplier in this case) you will be able to pass this around as any other variable and would be able to call it using

calculatedValueSupplier.apply();

The idea here being whether you have got optional value or not will be internal detail of your function and will not be in parameter. Thinking functions when thinking about optional as parameter is actually very useful technique that I have found.

As to your question whether you should actually do it or not is based on your preference, but as others said it makes your API ugly to say the least.

How to use the toString method in Java?

From the Object.toString docs:

Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:

getClass().getName() + '@' + Integer.toHexString(hashCode())

Example:

String[] mystr ={"a","b","c"};
System.out.println("mystr.toString: " + mystr.toString());

output:- mystr.toString: [Ljava.lang.String;@13aaa14a

Split code over multiple lines in an R script

I know this post is old, but I had a Situation like this and just want to share my solution. All the answers above work fine. But if you have a Code such as those in data.table chaining Syntax it becomes abit challenging. e.g. I had a Problem like this.

mass <- files[, Veg:=tstrsplit(files$file, "/")[1:4][[1]]][, Rain:=tstrsplit(files$file, "/")[1:4][[2]]][, Roughness:=tstrsplit(files$file, "/")[1:4][[3]]][, Geom:=tstrsplit(files$file, "/")[1:4][[4]]][time_[s]<=12000]

I tried most of the suggestions above and they didn´t work. but I figured out that they can be split after the comma within []. Splitting at ][ doesn´t work.

mass <- files[, Veg:=tstrsplit(files$file, "/")[1:4][[1]]][, 
    Rain:=tstrsplit(files$file, "/")[1:4][[2]]][, 
    Roughness:=tstrsplit(files$file, "/")[1:4][[3]]][, 
    Geom:=tstrsplit(files$file, "/")[1:4][[4]]][`time_[s]`<=12000]

How can I force a long string without any blank to be wrapped?

for block elements:

_x000D_
_x000D_
<textarea style="width:100px; word-wrap:break-word;">_x000D_
  ACTGATCGAGCTGAAGCGCAGTGCGATGCTTCGATGATGCTGACGATGCTACGATGCGAGCATCTACGATCAGTC_x000D_
</textarea>
_x000D_
_x000D_
_x000D_

for inline elements:

_x000D_
_x000D_
<span style="width:100px; word-wrap:break-word; display:inline-block;"> _x000D_
   ACTGATCGAGCTGAAGCGCAGTGCGATGCTTCGATGATGCTGACGATGCTACGATGCGAGCATCTACGATCAGTC_x000D_
</span>
_x000D_
_x000D_
_x000D_

Get div tag scroll position using JavaScript

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <script type="text/javascript">
        function scollPos() {
            var div = document.getElementById("myDiv").scrollTop;
            document.getElementById("pos").innerHTML = div;
        }
    </script>
</head>
<body>
    <form id="form1">
    <div id="pos">
    </div>
    <div id="myDiv" style="overflow: auto; height: 200px; width: 200px;" onscroll="scollPos();">
        Place some large content here
    </div>
    </form>
</body>
</html>

How are POST and GET variables handled in Python?

They are stored in the CGI fieldstorage object.

import cgi
form = cgi.FieldStorage()

print "The user entered %s" % form.getvalue("uservalue")

rawQuery(query, selectionArgs)

see below code it may help you.

String q = "SELECT * FROM customer";
Cursor mCursor = mDb.rawQuery(q, null);

or

String q = "SELECT * FROM customer WHERE _id = " + customerDbId  ;
Cursor mCursor = mDb.rawQuery(q, null);

How can I install Visual Studio Code extensions offline?

I've stored a script in my gist to download an extension from the marketplace using a PowerShell script. Feel free to comment of share it.

https://gist.github.com/azurekid/ca641c47981cf8074aeaf6218bb9eb58

[CmdletBinding()]
param
(
    [Parameter(Mandatory = $true)]
    [string] $Publisher,

    [Parameter(Mandatory = $true)]
    [string] $ExtensionName,

    [Parameter(Mandatory = $true)]
    [ValidateScript( {
            If ($_ -match "^([0-9].[0-9].[0-9])") {
                $True
            }
            else {
                Throw "$_ is not a valid version number. Version can only contain digits"
            }
        })]
    [string] $Version,

    [Parameter(Mandatory = $true)]
    [string] $OutputLocation
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

Write-Output "Publisher:        $($Publisher)"
Write-Output "Extension name:   $($ExtensionName)"
Write-Output "Version:          $($Version)"
Write-Output "Output location   $($OutputLocation)"

$baseUrl = "https://$($Publisher).gallery.vsassets.io/_apis/public/gallery/publisher/$($Publisher)/extension/$($ExtensionName)/$($Version)/assetbyname/Microsoft.VisualStudio.Services.VSIXPackage"
$outputFile = "$($Publisher)-$($ExtensionName)-$($Version).visx"

if (Test-Path $OutputLocation) {
    try {
        Write-Output "Retrieving extension..."
        [uri]::EscapeUriString($baseUrl) | Out-Null
        Invoke-WebRequest -Uri $baseUrl -OutFile "$OutputLocation\$outputFile"
    }
    catch {
        Write-Error "Unable to find the extension in the marketplace"
    }
}
else {
    Write-Output "The Path $($OutputLocation) does not exist"
}

How do I calculate the date in JavaScript three months prior to today?

This should handle addition/subtraction, just put a negative value in to subtract and a positive value to add. This also solves the month crossover problem.

function monthAdd(date, month) {
    var temp = date;
    temp = new Date(date.getFullYear(), date.getMonth(), 1);
    temp.setMonth(temp.getMonth() + (month + 1));
    temp.setDate(temp.getDate() - 1); 

    if (date.getDate() < temp.getDate()) { 
        temp.setDate(date.getDate()); 
    }

    return temp;    
}

Cassandra "no viable alternative at input"

Wrong syntax. Here you are:

insert into user_by_category (game_category,customer_id) VALUES ('Goku','12');

or:

insert into user_by_category ("game_category","customer_id") VALUES ('Kakarot','12');

The second one is normally used for case-sensitive column names.

database vs. flat files

This is an answer I've already given some time ago:

It depends entirely on the domain-specific application needs. A lot of times direct text file/binary files access can be extremely fast, efficient, as well as providing you all the file access capabilities of your OS's file system.

Furthermore, your programming language most likely already has a built-in module (or is easy to make one) for specific parsing.

If what you need is many appends (INSERTS?) and sequential/few access little/no concurrency, files are the way to go.

On the other hand, when your requirements for concurrency, non-sequential reading/writing, atomicity, atomic permissions, your data is relational by the nature etc., you will be better off with a relational or OO database.

There is a lot that can be accomplished with SQLite3, which is extremely light (under 300kb), ACID compliant, written in C/C++, and highly ubiquitous (if it isn't already included in your programming language -for example Python-, there is surely one available). It can be useful even on db files as big as 140 terabytes, or 128 tebibytes (Link to Database Size), possible more.

If your requirements where bigger, there wouldn't even be a discussion, go for a full-blown RDBMS.

As you say in a comment that "the system" is merely a bunch of scripts, then you should take a look at pgbash.

Validate that end date is greater than start date with jQuery

function endDate(){
    $.validator.addMethod("endDate", function(value, element) {
      var params = '.startDate';
        if($(element).parent().parent().find(params).val()!=''){
           if (!/Invalid|NaN/.test(new Date(value))) {
               return new Date(value) > new Date($(element).parent().parent().find(params).val());
            }
       return isNaN(value) && isNaN($(element).parent().parent().find(params).val()) || (parseFloat(value) > parseFloat($(element).parent().parent().find(params).val())) || value == "";              
      }else{
        return true;
      }
      },jQuery.format('must be greater than start date'));

}

function startDate(){
            $.validator.addMethod("startDate", function(value, element) {
            var params = '.endDate';
            if($(element).parent().parent().parent().find(params).val()!=''){
                 if (!/Invalid|NaN/.test(new Date(value))) {
                  return new Date(value) < new Date($(element).parent().parent().parent().find(params).val());
            }
           return isNaN(value) && isNaN($(element).parent().parent().find(params).val()) || (parseFloat(value) < parseFloat($(element).parent().parent().find(params).val())) || value == "";
                 }
                        else{
                     return true;
}

    }, jQuery.format('must be less than end date'));
}

Hope this will help :)

Change arrow colors in Bootstraps carousel

To customize the colors for the carousel controls, captions, and indicators using Sass you can include these variables

    $carousel-control-color: 
    $carousel-caption-color: 
    $carousel-indicator-active-bg: 

Select a date from date picker using Selenium webdriver

Here's a tidy solution where you provide the target date as a Calendar object.

// Used to translate the Month value of a JQuery calendar to the month value expected by a Calendar.
private static final Map<String,Integer> MONTH_TO_CALENDAR_INDEX = new HashMap<String,Integer>();
static {
    MONTH_TO_CALENDAR_INDEX.put("January",  0);
    MONTH_TO_CALENDAR_INDEX.put("February",1);
    MONTH_TO_CALENDAR_INDEX.put("March",2);
    MONTH_TO_CALENDAR_INDEX.put("April",3);
    MONTH_TO_CALENDAR_INDEX.put("May",4);
    MONTH_TO_CALENDAR_INDEX.put("June",5);
    MONTH_TO_CALENDAR_INDEX.put("July",6);
    MONTH_TO_CALENDAR_INDEX.put("August",7);
    MONTH_TO_CALENDAR_INDEX.put("September",8);
    MONTH_TO_CALENDAR_INDEX.put("October",9);
    MONTH_TO_CALENDAR_INDEX.put("November",10);
    MONTH_TO_CALENDAR_INDEX.put("December",11);
}

        // ====================================================================================================
        // setCalendarPicker
        // ====================================================================================================

        /**
         * Sets the value of specified web element while assuming the element is a JQuery calendar.
         * @param byOpen The By phrase that locates the control that opens the JQuery calendar when clicked.
         * @param byPicker The By phrase that locates the JQuery calendar.
         * @param targetDate The target date that you want set.
         * @throws AssertionError if the method is unable to set the date.
         */

        public void setCalendarPicker(By byOpen, By byPicker, Calendar targetDate) {

            // Open the JQuery calendar.
            WebElement opener = driver.findElement(byOpen);
            opener.click();

            // Locate the JQuery calendar.
            WebElement picker = driver.findElement(byPicker);

            // Calculate the target and current year-and-month as an integer where value = year*12+month.
            // The difference between the two is the number of months we have to move ahead or backward.
            int targetYearMonth = targetDate.get(Calendar.YEAR) * 12 + targetDate.get(Calendar.MONTH);
            int currentYearMonth = Integer.valueOf(picker.findElement(By.className("ui-datepicker-year")).getText()) * 12
                    + Integer.valueOf(MONTH_TO_CALENDAR_INDEX.get(picker.findElement(By.className("ui-datepicker-month")).getText()));
            // Calculate the number of months we need to move the JQuery calendar.
            int delta = targetYearMonth - currentYearMonth;
            // As a sanity check, let's not allow more than 10 years so that we don't inadvertently spin in a loop for zillions of months.
            if (Math.abs(delta) > 120) throw new AssertionError("Target date is more than 10 years away");

            // Push the JQuery calendar forward or backward as appropriate.
            if (delta > 0) {
                while (delta-- > 0) picker.findElement(By.className("ui-icon-circle-triangle-e")).click();
            } else if (delta < 0 ){
                while (delta++ < 0) picker.findElement(By.className("ui-icon-circle-triangle-w")).click();
            }

            // Select the day within the month.
            String dayOfMonth = String.valueOf(targetDate.get(Calendar.DAY_OF_MONTH));
            WebElement tableOfDays = picker.findElement(By.cssSelector("tbody:nth-child(2)"));
            for (WebElement we : tableOfDays.findElements(By.tagName("td"))) {
                if (dayOfMonth.equals(we.getText())) {
                    we.click();

                    // Send a tab to completely leave this control.  If the next control the user will access is another CalendarPicker,
                    // the picker might not get selected properly if we stay on the current control.
                    opener.sendKeys("\t");

                    return;
                }
            }

            throw new AssertionError(String.format("Unable to select specified day"));
        }

Convert a string to a double - is this possible?

Just use floatval().

E.g.:

$var = '122.34343';
$float_value_of_var = floatval($var);
echo $float_value_of_var; // 122.34343

And in case you wonder doubleval() is just an alias for floatval().

And as the other say, in a financial application, float values are critical as these are not precise enough. E.g. adding two floats could result in something like 12.30000000001 and this error could propagate.

AngularJS Directive Restrict A vs E

2 problems with elements:

  1. Bad support with old browsers.
  2. SEO - Google's engine doesn't like them.

Use Attributes.

Where does the @Transactional annotation belong?

Also, Spring recommends only using the annotation on concrete classes and not interfaces.

http://static.springsource.org/spring/docs/2.0.x/reference/transaction.html

UITableViewCell Selected Background Color on Multiple Selection

You can also set cell's selectionStyle to.none in interface builder. The same solution as @AhmedLotfy provided, only from IB.

enter image description here

Object creation on the stack/heap?

Actually, neither statement says anything about heap or stack. The code

Object o;

creates one of the following, depending on its context:

  • a local variable with automatic storage,
  • a static variable at namespace or file scope,
  • a member variable that designates the subobject of another object.

This means that the storage location is determined by the context in which the object is defined. In addition, the C++ standard does not talk about stack vs heap storage. Instead, it talks about storage duration, which can be either automatic, dynamic, static or thread-local. However, most implementations implement automatic storage via the call stack, and dynamic storage via the heap.

Local variables, which have automatic storage, are thus created on the stack. Static (and thread-local) objects are generally allocated in their own memory regions, neither on the stack nor on the heap. And member variables are allocated wherever the object they belong to is allocated. They have their containing object’s storage duration.

To illustrate this with an example:

struct Foo {
    Object o;
};

Foo foo;

int main() {
    Foo f;
    Foo* p = new Foo;
    Foo* pf = &f;
}

Now where is the object Foo::o (that is, the subobject o of an object of class Foo) created? It depends:

  • foo.o has static storage because foo has static storage, and therefore lives neither on the stack nor on the heap.
  • f.o has automatic storage since f has automatic storage (= it lives on the stack).
  • p->o has dynamic storage since *p has dynamic storage (= it lives on the heap).
  • pf->o is the same object as f.o because pf points to f.

In fact, both p and pf in the above have automatic storage. A pointer’s storage is indistinguishable from any other object’s, it is determined by context. Furthermore, the initialising expression has no effect on the pointer storage.

The pointee (= what the pointer points to) is a completely different matter, and could refer to any kind of storage: *p is dynamic, whereas *pf is automatic.

How to solve Permission denied (publickey) error when using Git?

This strange error, in my case was a symptom of gnome-keyring-daemon incorrectly naming the key to which it required a password.

I follow the steps outlined here, and entered the password via the terminal. The error, aka the confounding GUI interface, was resolved. See: https://askubuntu.com/questions/3045/how-to-disable-gnome-keyring

Syntax for creating a two-dimensional array in Java

These types of arrays are known as jagged arrays in Java:

int[][] multD = new int[3][];
multD[0] = new int[3];
multD[1] = new int[2];
multD[2] = new int[5];

In this scenario each row of the array holds the different number of columns. In the above example, the first row will hold three columns, the second row will hold two columns, and the third row holds five columns. You can initialize this array at compile time like below:

 int[][] multD = {{2, 4, 1}, {6, 8}, {7, 3, 6, 5, 1}};

You can easily iterate all elements in your array:

for (int i = 0; i<multD.length; i++) {
    for (int j = 0; j<multD[i].length; j++) {
        System.out.print(multD[i][j] + "\t");
    }
    System.out.println();
}

How to verify if $_GET exists?

Use and empty() whit negation (for test if not empty)

if(!empty($_GET['id'])) {
    // if get id is not empty
}

Using python map and other functional tools

Here's the solution you're looking for:

>>> foos = [1.0, 2.0, 3.0, 4.0, 5.0]
>>> bars = [1, 2, 3]
>>> [(x, bars) for x in foos]
[(1.0, [1, 2, 3]), (2.0, [1, 2, 3]), (3.0, [1, 2, 3]), (4.0, [1, 2, 3]), (5.0, [
1, 2, 3])]

I'd recommend using a list comprehension (the [(x, bars) for x in foos] part) over using map as it avoids the overhead of a function call on every iteration (which can be very significant). If you're just going to use it in a for loop, you'll get better speeds by using a generator comprehension:

>>> y = ((x, bars) for x in foos)
>>> for z in y:
...     print z
...
(1.0, [1, 2, 3])
(2.0, [1, 2, 3])
(3.0, [1, 2, 3])
(4.0, [1, 2, 3])
(5.0, [1, 2, 3])

The difference is that the generator comprehension is lazily loaded.

UPDATE In response to this comment:

Of course you know, that you don't copy bars, all entries are the same bars list. So if you modify any one of them (including original bars), you modify all of them.

I suppose this is a valid point. There are two solutions to this that I can think of. The most efficient is probably something like this:

tbars = tuple(bars)
[(x, tbars) for x in foos]

Since tuples are immutable, this will prevent bars from being modified through the results of this list comprehension (or generator comprehension if you go that route). If you really need to modify each and every one of the results, you can do this:

from copy import copy
[(x, copy(bars)) for x in foos]

However, this can be a bit expensive both in terms of memory usage and in speed, so I'd recommend against it unless you really need to add to each one of them.

Automating running command on Linux from Windows using PuTTY

Here is a totally out of the box solution.

  1. Install AutoHotKey (ahk)
  2. Map the script to a key (e.g. F9)
  3. In the ahk script, a) Ftp the commands (.ksh) file to the linux machine

    b) Use plink like below. Plink should be installed if you have putty.

plink sessionname -l username -pw password test.ksh

or

plink -ssh example.com -l username -pw password test.ksh

All the steps will be performed in sequence whenever you press F9 in windows.

SignalR - Sending a message to a specific user using (IUserIdProvider) *NEW 2.0.0*

For anyone trying to do this in asp.net core. You can use claims.

public class CustomEmailProvider : IUserIdProvider
{
    public virtual string GetUserId(HubConnectionContext connection)
    {
        return connection.User?.FindFirst(ClaimTypes.Email)?.Value;
    }
}

Any identifier can be used, but it must be unique. If you use a name identifier for example, it means if there are multiple users with the same name as the recipient, the message would be delivered to them as well. I have chosen email because it is unique to every user.

Then register the service in the startup class.

services.AddSingleton<IUserIdProvider, CustomEmailProvider>();

Next. Add the claims during user registration.

var result = await _userManager.CreateAsync(user, Model.Password);
if (result.Succeeded)
{
    await _userManager.AddClaimAsync(user, new Claim(ClaimTypes.Email, Model.Email));
}

To send message to the specific user.

public class ChatHub : Hub
{
    public async Task SendMessage(string receiver, string message)
    {
        await Clients.User(receiver).SendAsync("ReceiveMessage", message);
    }
}

Note: The message sender won't be notified the message is sent. If you want a notification on the sender's end. Change the SendMessage method to this.

public async Task SendMessage(string sender, string receiver, string message)
{
    await Clients.Users(sender, receiver).SendAsync("ReceiveMessage", message);
}

These steps are only necessary if you need to change the default identifier. Otherwise, skip to the last step where you can simply send messages by passing userIds or connectionIds to SendMessage. For more

how to do "press enter to exit" in batch

My guess is that rake is a batch program. When you invoke it without call, then control doesn't return to your build.bat. Try:

@echo off
cls
CALL rake
pause

Best data type to store money values in MySQL

Multiplies 10000 and stores as BIGINT, like "Currency" in Visual Basic and Office. See https://msdn.microsoft.com/en-us/library/office/gg264338.aspx

How to pass the button value into my onclick event function?

Maybe you can take a look at closure in JavaScript. Here is a working solution:

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
    <head>_x000D_
        <meta charset="utf-8" />_x000D_
        <title>Test</title>_x000D_
    </head>_x000D_
    <body>_x000D_
        <p class="button">Button 0</p>_x000D_
        <p class="button">Button 1</p>_x000D_
        <p class="button">Button 2</p>_x000D_
        <script>_x000D_
            var buttons = document.getElementsByClassName('button');_x000D_
            for (var i=0 ; i < buttons.length ; i++){_x000D_
              (function(index){_x000D_
                buttons[index].onclick = function(){_x000D_
                  alert("I am button " + index);_x000D_
                };_x000D_
              })(i)_x000D_
            }_x000D_
        </script>_x000D_
    </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Convert string to List<string> in one line?

I prefer this because it prevents a single item list with an empty item if your source string is empty:

  IEnumerable<string> namesList = 
      !string.isNullOrEmpty(names) ? names.Split(',') : Enumerable.Empty<string>();

How do I pick 2 random items from a Python set?

Use the random module: http://docs.python.org/library/random.html

import random
random.sample(set([1, 2, 3, 4, 5, 6]), 2)

This samples the two values without replacement (so the two values are different).

Differences between dependencyManagement and dependencies in Maven

Sorry I am very late to the party.

Let me try to explain the difference using mvn dependency:tree command

Consider the below example

Parent POM - My Project

<modules>
    <module>app</module>
    <module>data</module>
</modules>

<dependencies>
    <dependency>
        <groupId>com.google.guava</groupId>
        <artifactId>guava</artifactId>
        <version>19.0</version>
    </dependency>
</dependencies>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.9</version>
        </dependency>
    </dependencies>
</dependencyManagement>

Child POM - data module

<dependencies>
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
    </dependency>
</dependencies>

Child POM - app module (has no extra dependency, so leaving dependencies empty)

 <dependencies>
</dependencies>

On running mvn dependency:tree command, we get following result

Scanning for projects...
------------------------------------------------------------------------
Reactor Build Order:

MyProject
app
data

------------------------------------------------------------------------
Building MyProject 1.0-SNAPSHOT
------------------------------------------------------------------------

--- maven-dependency-plugin:2.8:tree (default-cli) @ MyProject ---
com.iamvickyav:MyProject:pom:1.0-SNAPSHOT
\- com.google.guava:guava:jar:19.0:compile

------------------------------------------------------------------------
Building app 1.0-SNAPSHOT
------------------------------------------------------------------------

--- maven-dependency-plugin:2.8:tree (default-cli) @ app ---
com.iamvickyav:app:jar:1.0-SNAPSHOT
\- com.google.guava:guava:jar:19.0:compile

------------------------------------------------------------------------
Building data 1.0-SNAPSHOT
------------------------------------------------------------------------

--- maven-dependency-plugin:2.8:tree (default-cli) @ data ---
com.iamvickyav:data:jar:1.0-SNAPSHOT
+- org.apache.commons:commons-lang3:jar:3.9:compile
\- com.google.guava:guava:jar:19.0:compile

Google guava is listed as dependency in every module (including parent), whereas the apache commons is listed as dependency only in data module (not even in parent module)

Add alternating row color to SQL Server Reporting services report

for group headers/footers:

=iif(RunningValue(*group on field*,CountDistinct,"*parent group name*") Mod 2,"White","AliceBlue")

You can also use this to “reset” the row color count within each group. I wanted the first detail row in each sub group to start with White and this solution (when used on the detail row) allowed that to happen:

=IIF(RunningValue(Fields![Name].Value, CountDistinct, "NameOfPartnetGroup") Mod 2, "White", "Wheat")

See: http://msdn.microsoft.com/en-us/library/ms159136(v=sql.100).aspx

Pandas: convert dtype 'object' to int

pandas >= 1.0

convert_dtypes

The (self) accepted answer doesn't take into consideration the possibility of NaNs in object columns.

df = pd.DataFrame({
     'a': [1, 2, np.nan], 
     'b': [True, False, np.nan]}, dtype=object) 
df                                                                         

     a      b
0    1   True
1    2  False
2  NaN    NaN

df['a'].astype(str).astype(int) # raises ValueError

This chokes because the NaN is converted to a string "nan", and further attempts to coerce to integer will fail. To avoid this issue, we can soft-convert columns to their corresponding nullable type using convert_dtypes:

df.convert_dtypes()                                                        

      a      b
0     1   True
1     2  False
2  <NA>   <NA>

df.convert_dtypes().dtypes                                                 

a      Int64
b    boolean
dtype: object

If your data has junk text mixed in with your ints, you can use pd.to_numeric as an initial step:

s = pd.Series(['1', '2', '...'])
s.convert_dtypes()  # converts to string, which is not what we want

0      1
1      2
2    ...
dtype: string 

# coerces non-numeric junk to NaNs
pd.to_numeric(s, errors='coerce')

0    1.0
1    2.0
2    NaN
dtype: float64

# one final `convert_dtypes` call to convert to nullable int
pd.to_numeric(s, errors='coerce').convert_dtypes() 

0       1
1       2
2    <NA>
dtype: Int64

"Undefined reference to" template class constructor

This is a common question in C++ programming. There are two valid answers to this. There are advantages and disadvantages to both answers and your choice will depend on context. The common answer is to put all the implementation in the header file, but there's another approach will will be suitable in some cases. The choice is yours.

The code in a template is merely a 'pattern' known to the compiler. The compiler won't compile the constructors cola<float>::cola(...) and cola<string>::cola(...) until it is forced to do so. And we must ensure that this compilation happens for the constructors at least once in the entire compilation process, or we will get the 'undefined reference' error. (This applies to the other methods of cola<T> also.)

Understanding the problem

The problem is caused by the fact that main.cpp and cola.cpp will be compiled separately first. In main.cpp, the compiler will implicitly instantiate the template classes cola<float> and cola<string> because those particular instantiations are used in main.cpp. The bad news is that the implementations of those member functions are not in main.cpp, nor in any header file included in main.cpp, and therefore the compiler can't include complete versions of those functions in main.o. When compiling cola.cpp, the compiler won't compile those instantiations either, because there are no implicit or explicit instantiations of cola<float> or cola<string>. Remember, when compiling cola.cpp, the compiler has no clue which instantiations will be needed; and we can't expect it to compile for every type in order to ensure this problem never happens! (cola<int>, cola<char>, cola<ostream>, cola< cola<int> > ... and so on ...)

The two answers are:

  • Tell the compiler, at the end of cola.cpp, which particular template classes will be required, forcing it to compile cola<float> and cola<string>.
  • Put the implementation of the member functions in a header file that will be included every time any other 'translation unit' (such as main.cpp) uses the template class.

Answer 1: Explicitly instantiate the template, and its member definitions

At the end of cola.cpp, you should add lines explicitly instantiating all the relevant templates, such as

template class cola<float>;
template class cola<string>;

and you add the following two lines at the end of nodo_colaypila.cpp:

template class nodo_colaypila<float>;
template class nodo_colaypila<std :: string>;

This will ensure that, when the compiler is compiling cola.cpp that it will explicitly compile all the code for the cola<float> and cola<string> classes. Similarly, nodo_colaypila.cpp contains the implementations of the nodo_colaypila<...> classes.

In this approach, you should ensure that all the of the implementation is placed into one .cpp file (i.e. one translation unit) and that the explicit instantation is placed after the definition of all the functions (i.e. at the end of the file).

Answer 2: Copy the code into the relevant header file

The common answer is to move all the code from the implementation files cola.cpp and nodo_colaypila.cpp into cola.h and nodo_colaypila.h. In the long run, this is more flexible as it means you can use extra instantiations (e.g. cola<char>) without any more work. But it could mean the same functions are compiled many times, once in each translation unit. This is not a big problem, as the linker will correctly ignore the duplicate implementations. But it might slow down the compilation a little.

Summary

The default answer, used by the STL for example and in most of the code that any of us will write, is to put all the implementations in the header files. But in a more private project, you will have more knowledge and control of which particular template classes will be instantiated. In fact, this 'bug' might be seen as a feature, as it stops users of your code from accidentally using instantiations you have not tested for or planned for ("I know this works for cola<float> and cola<string>, if you want to use something else, tell me first and will can verify it works before enabling it.").

Finally, there are three other minor typos in the code in your question:

  • You are missing an #endif at the end of nodo_colaypila.h
  • in cola.h nodo_colaypila<T>* ult, pri; should be nodo_colaypila<T> *ult, *pri; - both are pointers.
  • nodo_colaypila.cpp: The default parameter should be in the header file nodo_colaypila.h, not in this implementation file.

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Try restarting the server with

sudo /usr/local/mysql/support-files/mysql.server start

If there is any error then follow the below steps

  1. mysqld

You will see the the below log. Notice the highlighted portion of the MySQL directory here

mysqld: Can't change dir to '/usr/local/mysql-5.7.14-osx10.11-x86_64/data/' (Errcode: 13 - Permission denied) 2016-10-04T14:09:19.392581Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2016-10-04T14:09:19.392847Z 0 [Warning] Insecure configuration for --secure-file-priv: Current value does not restrict location of generated files. Consider setting it to a valid, non-empty path. 2016-10-04T14:09:19.392921Z 0 [Note] mysqld (mysqld 5.7.14) starting as process 1402 ... 2016-10-04T14:09:19.397569Z 0 [Warning] Can't create test file
/usr/local/mysql-5.7.14-osx10.11-x86_64/data/Sudharshan.lower-test
2016-10-04T14:09:19.397597Z 0 [Warning] Can't create test file /usr/local/mysql-5.7.14-osx10.11-x86_64/data/Sudharshan.lower-test
2016-10-04T14:09:19.397712Z 0 [ERROR] failed to set datadir to /usr/local/mysql-5.7.14-osx10.11-x86_64/data/
2016-10-04T14:09:19.397776Z 0 [ERROR] Aborting
2016-10-04T14:09:19.397795Z 0 [Note] Binlog end
2016-10-04T14:09:19.397925Z 0 [Note] mysqld: Shutdown complete

  1. sudo chown -R _mysql:_mysql /usr/local/mysql-5.7.14-osx10.11-x86_64

Note the MySQL folder path /usr/local on the the previous log, and in my case it was mysql-5.7.14-osx10.11-x86_64, and you have to update it based on the log you get on your machine to provide read access to the MySQL directory

  1. sudo /usr/local/mysql/support-files/mysql.server start

Starting MySQL
SUCCESS!

Python equivalent to 'hold on' in Matlab

The hold on feature is switched on by default in matplotlib.pyplot. So each time you evoke plt.plot() before plt.show() a drawing is added to the plot. Launching plt.plot() after the function plt.show() leads to redrawing the whole picture.

Maven and Spring Boot - non resolvable parent pom - repo.spring.io (Unknown host)

As people already mentioned, it could be internet problems or proxy configuration.
I found this question when I was searching about the same problem. In my case, it was proxy configuration.
Answers posted here didn't solve my issue, because every link suggest a configuration that shows the username and passoword and I can't use it.
I was searching about it elsewere and I found a configuration to be made on settings.xml, I needed to make some changes. Here is the final code:

<profiles>
    <profile>
       <id>MavenRepository</id>
           <repositories>
            <repository>
                <id>central</id>
                <url>https://repo1.maven.org/maven2</url>
                <snapshots>
                    <enabled>false</enabled>
                </snapshots>
                <releases>
                    <enabled>true</enabled>
                </releases>
            </repository>
        </repositories>
    </profile>
</profiles>

<activeProfiles>
    <activeProfile>MavenRepository</activeProfile>
</activeProfiles>

I hope be useful.

How do I bind Twitter Bootstrap tooltips to dynamically created elements?

For me, this js reproduces the same problem that happens with Paola

My solution:

$(document.body).tooltip({selector: '[title]'})
.on('click mouseenter mouseleave','[title]', function(ev) {
    $(this).tooltip('mouseenter' === ev.type? 'show': 'hide');
});

gcloud command not found - while installing Google Cloud SDK

I had the same problem and it was because the ~/.bash_profile had invalid fi statements.

The fix:

  1. Execute command sudo nano ~/.bash_profile
  2. Removed closing fi statements (the ones missing an opening if)
  3. Save .bash_profile changes
  4. Execute command source ~/.bash_profile

Nested ifelse statement

You can create the vector idnat2 without if and ifelse.

The function replace can be used to replace all occurrences of "colony" with "overseas":

idnat2 <- replace(idbp, idbp == "colony", "overseas")

Razor View Without Layout

Do you have a _ViewStart.cshtml in this directory? I had the same problem you're having when I tried using _ViewStart. Then I renamed it _mydefaultview, moved it to the Views/Shared directory, and switched to specifying no view in cshtml files where I don't want it, and specifying _mydefaultview for the rest. Don't know why this was necessary, but it worked.

CodeIgniter activerecord, retrieve last insert id?

Shame on me...

I looked at the user guide and the first function is $this->db->insert_id();

This also works with activerecord inserts...

EDIT: I updated the link

Unicode, UTF, ASCII, ANSI format differences

Going down your list:

  • "Unicode" isn't an encoding, although unfortunately, a lot of documentation imprecisely uses it to refer to whichever Unicode encoding that particular system uses by default. On Windows and Java, this often means UTF-16; in many other places, it means UTF-8. Properly, Unicode refers to the abstract character set itself, not to any particular encoding.
  • UTF-16: 2 bytes per "code unit". This is the native format of strings in .NET, and generally in Windows and Java. Values outside the Basic Multilingual Plane (BMP) are encoded as surrogate pairs. These used to be relatively rarely used, but now many consumer applications will need to be aware of non-BMP characters in order to support emojis.
  • UTF-8: Variable length encoding, 1-4 bytes per code point. ASCII values are encoded as ASCII using 1 byte.
  • UTF-7: Usually used for mail encoding. Chances are if you think you need it and you're not doing mail, you're wrong. (That's just my experience of people posting in newsgroups etc - outside mail, it's really not widely used at all.)
  • UTF-32: Fixed width encoding using 4 bytes per code point. This isn't very efficient, but makes life easier outside the BMP. I have a .NET Utf32String class as part of my MiscUtil library, should you ever want it. (It's not been very thoroughly tested, mind you.)
  • ASCII: Single byte encoding only using the bottom 7 bits. (Unicode code points 0-127.) No accents etc.
  • ANSI: There's no one fixed ANSI encoding - there are lots of them. Usually when people say "ANSI" they mean "the default locale/codepage for my system" which is obtained via Encoding.Default, and is often Windows-1252 but can be other locales.

There's more on my Unicode page and tips for debugging Unicode problems.

The other big resource of code is unicode.org which contains more information than you'll ever be able to work your way through - possibly the most useful bit is the code charts.

How to detect control+click in Javascript from an onclick div attribute?

Because it's been a several years since this question was first asked, the other answers are outdated or incomplete.

Here's the code for a modern implementation using jQuery:

$( 'div#1' ).on( 'click', function( event ) {
    if ( event.ctrlKey ) {
        //is ctrl + click
    } else {
        //normal click
    }
} );

As for detecting right-clicks, this was correctly provided by another user but I'll list it here just to have everything in one place.

$( 'div#1' ).on( 'contextmenu', function( event ) {
    // right-click handler
} ) ;

How do you change the value inside of a textfield flutter?

You can use the text editing controller to manipulate the value inside a textfield.

var textController = new TextEditingController();

Now, create a new textfield and set textController as the controller for the textfield as shown below.

 new TextField(controller: textController)

Now, create a RaisedButton anywhere in your code and set the desired text in the onPressed method of the RaisedButton.

new RaisedButton(
       onPressed: () {
          textController.text = "New text";
       }
    ),

Git pushing to remote branch

First, let's note that git push "wants" two more arguments and will make them up automatically if you don't supply them. The basic command is therefore git push remote refspec.

The remote part is usually trivial as it's almost always just the word origin. The trickier part is the refspec. Most commonly, people write a branch name here: git push origin master, for instance. This uses your local branch to push to a branch of the same name1 on the remote, creating it if necessary. But it doesn't have to be just a branch name.

In particular, a refspec has two colon-separated parts. For git push, the part on the left identifies what to push,2 and the part on the right identifies the name to give to the remote. The part on the left in this case would be branch_name and the part on the right would be branch_name_test. For instance:

git push origin foo:foo_test

As you are doing the push, you can tell your git push to set your branch's upstream name at the same time, by adding -u to the git push options. Setting the upstream name makes your git save the foo_test (or whatever) name, so that a future git push with no arguments, while you're on the foo branch, can try to push to foo_test on the remote (git also saves the remote, origin in this case, so that you don't have to enter that either).

You need only pass -u once: it basically just runs git branch --set-upstream-to for you. (If you pass -u again later, it re-runs the upstream-setting, changing it as directed; or you can run git branch --set-upstream-to yourself.)

However, if your git is 2.0 or newer, and you have not set any special configuration, you will run into the same kind of thing that had me enter footnote 1 above: push.default will be set to simple, which will refuse to push because the upstream's name differs from your own local name. If you set push.default to upstream, git will stop complaining—but the simplest solution is just to rename your local branch first, so that the local and remote names match. (What settings to set, and/or whether to rename your branch, are up to you.)


1More precisely, git consults your remote.remote.push setting to derive the upstream half of the refspec. If you haven't set anything here, the default is to use the same name.

2This doesn't have to be a branch name. For instance, you can supply HEAD, or a commit hash, here. If you use something other than a branch name, you may have to spell out the full refs/heads/branch on the right, though (it depends on what names are already on the remote).

what is right way to do API call in react js?

A clean way is to make an asynchronous API call inside componentDidMount with try/catch function.

When we called an API, we receive a response. Then we apply JSON method on it, to convert the response into a JavaScript object. Then we take from that response object only his child object named "results" (data.results).

In the beginning we defined "userList" in state as an empty array. As soon as we make the API call and receive data from that API, we assign the "results" to userList using setState method.

Inside the render function we tell that userList will be coming from state. Since the userList is an array of objects we map through it, to display a picture, a name and a phone number of each object "user". To retrieve this information we use dot notation (e.g. user.phone).

NOTE: depending on your API, your response may look different. Console.log the whole "response" to see which variables you need from it, and then assign them in setState.

UserList.js

import React, { Component } from "react";

export default class UserList extends Component {
   state = {
      userList: [], // list is empty in the beginning
      error: false
   };

   componentDidMount() {
       this.getUserList(); // function call
   }

   getUserList = async () => {
       try { //try to get data
           const response = await fetch("https://randomuser.me/api/");
           if (response.ok) { // ckeck if status code is 200
               const data = await response.json();
               this.setState({ userList: data.results});
           } else { this.setState({ error: true }) }
       } catch (e) { //code will jump here if there is a network problem
   this.setState({ error: true });
  }
};

  render() {
  const { userList, error } = this.state
      return (
          <div>
            {userList.length > 0 && userList.map(user => (
              <div key={user}>
                  <img src={user.picture.medium} alt="user"/>
                  <div>
                      <div>{user.name.first}{user.name.last}</div>
                      <div>{user.phone}</div>
                      <div>{user.email}</div>
                  </div>
              </div>
            ))}
            {error && <div>Sorry, can not display the data</div>}
          </div>
      )
}}

Is there a concise way to iterate over a stream with indices in Java 8?

The cleanest way is to start from a stream of indices:

String[] names = {"Sam", "Pamela", "Dave", "Pascal", "Erik"};
IntStream.range(0, names.length)
         .filter(i -> names[i].length() <= i)
         .mapToObj(i -> names[i])
         .collect(Collectors.toList());

The resulting list contains "Erik" only.


One alternative which looks more familiar when you are used to for loops would be to maintain an ad hoc counter using a mutable object, for example an AtomicInteger:

String[] names = {"Sam", "Pamela", "Dave", "Pascal", "Erik"};
AtomicInteger index = new AtomicInteger();
List<String> list = Arrays.stream(names)
                          .filter(n -> n.length() <= index.incrementAndGet())
                          .collect(Collectors.toList());

Note that using the latter method on a parallel stream could break as the items would not necesarily be processed "in order".

RegEx for matching "A-Z, a-z, 0-9, _" and "."

regex: /^[a-zA-Z0-9_.]$/i

This works

A weighted version of random.choice

As of Python v3.6, random.choices could be used to return a list of elements of specified size from the given population with optional weights.

random.choices(population, weights=None, *, cum_weights=None, k=1)

  • population : list containing unique observations. (If empty, raises IndexError)

  • weights : More precisely relative weights required to make selections.

  • cum_weights : cumulative weights required to make selections.

  • k : size(len) of the list to be outputted. (Default len()=1)


Few Caveats:

1) It makes use of weighted sampling with replacement so the drawn items would be later replaced. The values in the weights sequence in itself do not matter, but their relative ratio does.

Unlike np.random.choice which can only take on probabilities as weights and also which must ensure summation of individual probabilities upto 1 criteria, there are no such regulations here. As long as they belong to numeric types (int/float/fraction except Decimal type) , these would still perform.

>>> import random
# weights being integers
>>> random.choices(["white", "green", "red"], [12, 12, 4], k=10)
['green', 'red', 'green', 'white', 'white', 'white', 'green', 'white', 'red', 'white']
# weights being floats
>>> random.choices(["white", "green", "red"], [.12, .12, .04], k=10)
['white', 'white', 'green', 'green', 'red', 'red', 'white', 'green', 'white', 'green']
# weights being fractions
>>> random.choices(["white", "green", "red"], [12/100, 12/100, 4/100], k=10)
['green', 'green', 'white', 'red', 'green', 'red', 'white', 'green', 'green', 'green']

2) If neither weights nor cum_weights are specified, selections are made with equal probability. If a weights sequence is supplied, it must be the same length as the population sequence.

Specifying both weights and cum_weights raises a TypeError.

>>> random.choices(["white", "green", "red"], k=10)
['white', 'white', 'green', 'red', 'red', 'red', 'white', 'white', 'white', 'green']

3) cum_weights are typically a result of itertools.accumulate function which are really handy in such situations.

From the documentation linked:

Internally, the relative weights are converted to cumulative weights before making selections, so supplying the cumulative weights saves work.

So, either supplying weights=[12, 12, 4] or cum_weights=[12, 24, 28] for our contrived case produces the same outcome and the latter seems to be more faster / efficient.

how can I set visible back to true in jquery

Depends, if i remember correctly i think asp.net won't render the html object out when you set visible to false.

If you want to be able to control it from the client side, then you better just include the css value to set it invisible rather than using visible =false.

vertical divider between two columns in bootstrap

_x000D_
_x000D_
.row.vertical-divider {_x000D_
  overflow: hidden;_x000D_
}_x000D_
.row.vertical-divider > div[class^="col-"] {_x000D_
  text-align: center;_x000D_
  padding-bottom: 100px;_x000D_
  margin-bottom: -100px;_x000D_
  border-left: 3px solid #F2F7F9;_x000D_
  border-right: 3px solid #F2F7F9;_x000D_
}_x000D_
.row.vertical-divider div[class^="col-"]:first-child {_x000D_
  border-left: none;_x000D_
}_x000D_
.row.vertical-divider div[class^="col-"]:last-child {_x000D_
  border-right: none;_x000D_
}
_x000D_
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" rel="stylesheet" />_x000D_
<div class="row vertical-divider" style="margin-top: 30px">_x000D_
  <div class="col-xs-6">Hi there</div>_x000D_
  <div class="col-xs-6">Hi world<br/>hi world</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Convert Map<String,Object> to Map<String,String>

If your Objects are containing of Strings only, then you can do it like this:

Map<String,Object> map = new HashMap<String,Object>(); //Object is containing String
Map<String,String> newMap =new HashMap<String,String>();
for (Map.Entry<String, Object> entry : map.entrySet()) {
       if(entry.getValue() instanceof String){
            newMap.put(entry.getKey(), (String) entry.getValue());
          }
 }

If every Objects are not String then you can replace (String) entry.getValue() into entry.getValue().toString().

Ordering issue with date values when creating pivot tables

The problem I had was that although the source data was correctly formatted as 'date' dd/mm/yyyy, the pivot table placed (for example) 22/05/2019 between 16/05/2019 and 17/05/2019. This data was visible in the pivot table, but in the wrong place. In addition, the Pivot chart refused to show that data for that date even though the 'Date' filter allowed it to be selected.

In my case, I had to:

  1. From the Pivot Chart,open the 'Date' Filter menu.

  2. select the 'Sort Oldest to Newest' option.

  3. Bingo! The Pivot chart now shows the missing date data.

Android set height and width of Custom view programmatically

you can set the height and width of a view in a relative layout like this

ViewGroup.LayoutParams params = view.getLayoutParams();
params.height = 130;
view.setLayoutParams(params);

Get Value of Radio button group

Your quotes only need to surround the value part of the attribute-equals selector, [attr='val'], like this:

$('a#check_var').click(function() {
  alert($("input:radio[name='r']:checked").val()+ ' '+
        $("input:radio[name='s']:checked").val());
});?

You can see the working version here.

Sort an ArrayList based on an object field

You can use the Bean Comparator to sort on any property in your custom class.

SQL query to group by day

For PostgreSQL:

GROUP BY to_char(timestampfield, 'yyyy-mm-dd')

or using cast:

GROUP BY timestampfield::date

if you want speed, use the second option and add an index:

CREATE INDEX tablename_timestampfield_date_idx ON  tablename(date(timestampfield));

How can I display the users profile pic using the facebook graph api?

The returned data is the binary data of the image type. If you use JavaScript to retrieve the user photo, please get the photo data as blob type in a XMLHttpRequest, and then retrieve the blob URL from the response. For your reference:

 var request = new XMLHttpRequest;
 var photoUri=config.endpoints.graphApiUri + "/v1.0/me/photo/$value";
 request.open("GET",photoUri);
 request.setRequestHeader("Authorization","Bearer "+token);
 request.responseType = "blob";
 request.onload = function (){
        if(request.readyState == 4 && request.status == 200){
               var image = document.createElement("img");
               var url = window.URL || window.webkitURL;
               var blobUrl = url.createObjectURL(request.response);
               image.src = blobUrl;
               document.getElementById("UserShow").appendChild(image);
        }
 };
 request.send(null); 

How to check if a column exists in a SQL Server table?

Yet another variation...

SELECT 
  Count(*) AS existFlag 
FROM 
  sys.columns 
WHERE 
  [name] = N 'ColumnName' 
  AND [object_id] = OBJECT_ID(N 'TableName')

How can I change the user on Git Bash?

For Mac Users

I am using Mac and I was facing same problem while I was trying to push a project from Android Studio. The reason for that other user had previously logged into Github and his credentials were saved in Keychain Access.

You need to remove those credentials from Keychain Access and then try to push.

Hope it help to Mac users.

CMD (command prompt) can't go to the desktop

You need to use the change directory command 'cd' to change directory

cd C:\Users\MyName\Desktop

you can use cd \d to change the drive as well.

link for additional resources http://ss64.com/nt/cd.html

Graphical user interface Tutorial in C

The two most usual choices are GTK+, which has documentation links here, and is mostly used with C; or Qt which has documentation here and is more used with C++.

I posted these two as you do not specify an operating system and these two are pretty cross-platform.

How many bits or bytes are there in a character?

It depends what is the character and what encoding it is in:

  • An ASCII character in 8-bit ASCII encoding is 8 bits (1 byte), though it can fit in 7 bits.

  • An ISO-8895-1 character in ISO-8859-1 encoding is 8 bits (1 byte).

  • A Unicode character in UTF-8 encoding is between 8 bits (1 byte) and 32 bits (4 bytes).

  • A Unicode character in UTF-16 encoding is between 16 (2 bytes) and 32 bits (4 bytes), though most of the common characters take 16 bits. This is the encoding used by Windows internally.

  • A Unicode character in UTF-32 encoding is always 32 bits (4 bytes).

  • An ASCII character in UTF-8 is 8 bits (1 byte), and in UTF-16 - 16 bits.

  • The additional (non-ASCII) characters in ISO-8895-1 (0xA0-0xFF) would take 16 bits in UTF-8 and UTF-16.

That would mean that there are between 0.03125 and 0.125 characters in a bit.

How to Make Laravel Eloquent "IN" Query?

If you are using Query builder then you may use a blow

DB::table(Newsletter Subscription)
->select('*')
->whereIn('id', $send_users_list)
->get()

If you are working with Eloquent then you can use as below

$sendUsersList = Newsletter Subscription:: select ('*')
                ->whereIn('id', $send_users_list)
                ->get();

Exception is never thrown in body of corresponding try statement

A catch-block in a try statement needs to catch exactly the exception that the code inside the try {}-block can throw (or a super class of that).

try {
    //do something that throws ExceptionA, e.g.
    throw new ExceptionA("I am Exception Alpha!");
}
catch(ExceptionA e) {
    //do something to handle the exception, e.g.
    System.out.println("Message: " + e.getMessage());
}

What you are trying to do is this:

try {
    throw new ExceptionB("I am Exception Bravo!");
}
catch(ExceptionA e) {
    System.out.println("Message: " + e.getMessage());
}

This will lead to an compiler error, because your java knows that you are trying to catch an exception that will NEVER EVER EVER occur. Thus you would get: exception ExceptionA is never thrown in body of corresponding try statement.

Cannot implicitly convert type 'System.Linq.IQueryable' to 'System.Collections.Generic.IList'

To convert IQuerable or IEnumerable to a list, you can do one of the following:

IQueryable<object> q = ...;
List<object> l = q.ToList();

or:

IQueryable<object> q = ...;
List<object> l = new List<object>(q);

How to SHUTDOWN Tomcat in Ubuntu?

if you have yout tomcat installed you can do :

sh path2tomcat/bin/shutdown.sh

PHP code to get selected text of a combo box

Put whatever you want to send to PHP in the value attribute.

  <select id="cmbMake" name="Make" >
     <option value="">Select Manufacturer</option>
     <option value="--Any--">--Any--</option>
     <option value="Toyota">Toyota</option>
     <option value="Nissan">Nissan</option>
  </select>

You can also omit the value attribute. It defaults to using the text.

If you don't want to change the HTML, you can put an array in your PHP to translate the values:

$makes = array(2 => 'Toyota',
               3 => 'Nissan');

$maker = $makes[$_POST['Make']];

Filtering a list of strings based on contents

# To support matches from the beginning, not any matches:

items = ['a', 'ab', 'abc', 'bac']
prefix = 'ab'

filter(lambda x: x.startswith(prefix), items)

What does "Object reference not set to an instance of an object" mean?

If I have the class:

public class MyClass
{
   public void MyMethod()
   {

   }
}

and I then do:

MyClass myClass = null;
myClass.MyMethod();

The second line throws this exception becuase I'm calling a method on a reference type object that is null (I.e. has not been instantiated by calling myClass = new MyClass())

Placeholder Mixin SCSS/CSS

To avoid 'Unclosed block: CssSyntaxError' errors being thrown from sass compilers add a ';' to the end of @content.

@mixin placeholder {
   ::-webkit-input-placeholder { @content;}
   :-moz-placeholder           { @content;}
   ::-moz-placeholder          { @content;}
   :-ms-input-placeholder      { @content;}
}

What is the difference between docker-compose ports vs expose

Ports This section is used to define the mapping between the host server and Docker container.

ports:
   - 10005:80

It means the application running inside the container is exposed at port 80. But external system/entity cannot access it, so it need to be mapped to host server port.

Note: you have to open the host port 10005 and modify firewall rules to allow external entities to access the application.

They can use

http://{host IP}:10005

something like this

EXPOSE This is exclusively used to define the port on which application is running inside the docker container.

You can define it in dockerfile as well. Generally, it is good and widely used practice to define EXPOSE inside dockerfile because very rarely anyone run them on other port than default 80 port

How to use not contains() in xpath?

I need to select every production with a category that doesn't contain "Business"

Although I upvoted @Arran's answer as correct, I would also add this... Strictly interpreted, the OP's specification would be implemented as

//production[category[not(contains(., 'Business'))]]

rather than

//production[not(contains(category, 'Business'))]

The latter selects every production whose first category child doesn't contain "Business". The two XPath expressions will behave differently when a production has no category children, or more than one.

It doesn't make any difference in practice as long as every <production> has exactly one <category> child, as in your short example XML. Whether you can always count on that being true or not, depends on various factors, such as whether you have a schema that enforces that constraint. Personally, I would go for the more robust option, since it doesn't "cost" much... assuming your requirement as stated in the question is really correct (as opposed to e.g. 'select every production that doesn't have a category that contains "Business"').

A potentially dangerous Request.Form value was detected from the client

If you're using framework 4.0 then the entry in the web.config (<pages validateRequest="false" />)

<configuration>
    <system.web>
        <pages validateRequest="false" />
    </system.web>
</configuration>

If you're using framework 4.5 then the entry in the web.config (requestValidationMode="2.0")

<system.web>
    <compilation debug="true" targetFramework="4.5" />
    <httpRuntime targetFramework="4.5" requestValidationMode="2.0"/>
</system.web>

If you want for only single page then, In you aspx file you should put the first line as this :

<%@ Page EnableEventValidation="false" %>

if you already have something like <%@ Page so just add the rest => EnableEventValidation="false" %>

I recommend not to do it.

Error in file(file, "rt") : cannot open the connection

Error in file(file, "rt") :

I just faced the same error and resolved by removing spacing in address using paste0 instead of paste

filepath=paste0(directory,"/",filename[1],sep="")

How to unit test abstract classes: extend with stubs?

To make an unit test specifically on the abstract class, you should derive it for testing purpose, test base.method() results and intended behaviour when inheriting.

You test a method by calling it so test an abstract class by implementing it...

Fatal Error: Allowed Memory Size of 134217728 Bytes Exhausted (CodeIgniter + XML-RPC)

For Drupal users, this Chris Lane's answer of:

ini_set('memory_limit', '-1');

works but we need to put it just after the opening

<?php

tag in the index.php file in your site's root directory.

Sum function in VBA

Function is not a property/method from range.

If you want to sum values then use the following:

Range("A1").Value = Application.Sum(Range(Cells(2, 1), Cells(3, 2)))

EDIT:

if you want the formula then use as follows:

Range("A1").Formula = "=SUM(" & Range(Cells(2, 1), Cells(3, 2)).Address(False, False) & ")"

'The two false after Adress is to define the address as relative (A2:B3).
'If you omit the parenthesis clause or write True instead, you can set the address
'as absolute ($A$2:$B$3).

In case you are allways going to use the same range address then you can use as Rory sugested:

Range("A1").Formula ="=Sum(A2:B3)"

R - " missing value where TRUE/FALSE needed "

Can you change the if condition to this:

if (!is.na(comments[l])) print(comments[l]);

You can only check for NA values with is.na().

How to fix Error: listen EADDRINUSE while using nodejs?

if you want to solve this

$ node server events.js:141 throw er; // Unhandled 'error' event ^

Error: listen EADDRINUSE :::3000 at Object.exports._errnoException (util.js:907:11) at exports._exceptionWithHostPort (util.js:930:20) at Server._listen2 (net.js:1250:14) at listen (net.js:1286:10) at Server.listen (net.js:1382:5) at EventEmitter.listen (C:\sendbox\mean\node_modules\express\lib\application .js:617:24) at Object. (C:\sendbox\mean\server.js:28:5) at Module._compile (module.js:409:26) at Object.Module._extensions..js (module.js:416:10) at Module.load (module.js:343:32)

change your port number to 8000

R multiple conditions in if statement

Read this thread R - boolean operators && and ||.

Basically, the & is vectorized, i.e. it acts on each element of the comparison returning a logical array with the same dimension as the input. && is not, returning a single logical.

Assign multiple values to array in C

With code like this:

const int node_ct = 8;
const int expected[node_ct] = { 1, 3, 4, 2, 5, 6, 7, 8 };

And in the configure.ac

AC_PROG_CC_C99

The compiler on my dev box was happy. The compiler on the server complained with:

error: variable-sized object may not be initialized
   const int expected[node_ct] = { 1, 3, 4, 2, 5, 6, 7, 8 };

and

warning: excess elements in array initializer
   const int expected[node_ct] = { 1, 3, 4, 2, 5, 6, 7, 8 };

for each element

It doesn't complain at all about, for example:

int expected[] = { 1, 2, 3, 4, 5 };

however, I decided that I like the check on size.

Rather than fighting, I went with a varargs initializer:

#include <stdarg.h>

void int_array_init(int *a, const int ct, ...) {
  va_list args;
  va_start(args, ct);
  for(int i = 0; i < ct; ++i) {
    a[i] = va_arg(args, int);
  }
  va_end(args);
}

called like,

const int node_ct = 8;
int expected[node_ct];
int_array_init(expected, node_ct, 1, 3, 4, 2, 5, 6, 7, 8);

As such, the varargs support is more robust than the support for the array initializer.

Someone might be able to do something like this in a macro.

Find PR with sample code at https://github.com/wbreeze/davenport/pull/15/files

Regarding https://stackoverflow.com/a/3535455/608359 from @paxdiablo, I liked it; but, felt insecure about having the number of times the initializaion pointer advances synchronized with the number of elements allocated to the array. Worst case, the initializing pointer moves beyond the allocated length. As such, the diff in the PR contains,

  int expected[node_ct];
- int *p = expected;
- *p++ = 1; *p++ = 2; *p++ = 3; *p++ = 4;
+ int_array_init(expected, node_ct, 1, 2, 3, 4);

The int_array_init method will safely assign junk if the number of arguments is fewer than the node_ct. The junk assignment ought to be easier to catch and debug.

Update only specific fields in a models.Model

To update a subset of fields, you can use update_fields:

survey.save(update_fields=["active"]) 

The update_fields argument was added in Django 1.5. In earlier versions, you could use the update() method instead:

Survey.objects.filter(pk=survey.pk).update(active=True)

How to save an image to localStorage and display it on the next page?

I wrote a little 2,2kb library of saving image in localStorage JQueryImageCaching Usage:

<img data-src="path/to/image">
<script>
    $('img').imageCaching();
</script>

latex large division sign in a math formula

Another option is to use \dfrac instead of \frac, which makes the whole fraction larger and hence more readable.

And no, I don't know if there is an option to get something in between \frac and \dfrac, sorry.

$(window).height() vs $(document).height

AFAIK $(window).height(); returns the height of your window and $(document).height(); returns the height of your document

How can I close a window with Javascript on Mozilla Firefox 3?

self.close() does not work, are you sure you closing a window and not a script generated popup ?

you guys might want to look at this : https://bugzilla.mozilla.org/show_bug.cgi?id=183697

Stick button to right side of div

Use position property

style="position: absolute;right:0;top:0"

How to write a unit test for a Spring Boot Controller endpoint

Let assume i am having a RestController with GET/POST/PUT/DELETE operations and i have to write unit test using spring boot.I will just share code of RestController class and respective unit test.Wont be sharing any other related code to the controller ,can have assumption on that.

@RestController
@RequestMapping(value = “/myapi/myApp” , produces = {"application/json"})
public class AppController {


    @Autowired
    private AppService service;

    @GetMapping
    public MyAppResponse<AppEntity> get() throws Exception {

        MyAppResponse<AppEntity> response = new MyAppResponse<AppEntity>();
        service.getApp().stream().forEach(x -> response.addData(x));    
        return response;
    }


    @PostMapping
    public ResponseEntity<HttpStatus> create(@RequestBody AppRequest request) throws Exception {
        //Validation code       
        service.createApp(request);

        return ResponseEntity.ok(HttpStatus.OK);
    }

    @PutMapping
    public ResponseEntity<HttpStatus> update(@RequestBody IDMSRequest request) throws Exception {

        //Validation code
        service.updateApp(request);

        return ResponseEntity.ok(HttpStatus.OK);
    }

    @DeleteMapping
    public ResponseEntity<HttpStatus> delete(@RequestBody AppRequest request) throws Exception {

        //Validation        
        service.deleteApp(request.id);

        return ResponseEntity.ok(HttpStatus.OK);
    }

}

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes = Main.class)
@WebAppConfiguration
public abstract class BaseTest {
   protected MockMvc mvc;
   @Autowired
   WebApplicationContext webApplicationContext;

   protected void setUp() {
      mvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
   }
   protected String mapToJson(Object obj) throws JsonProcessingException {
      ObjectMapper objectMapper = new ObjectMapper();
      return objectMapper.writeValueAsString(obj);
   }
   protected <T> T mapFromJson(String json, Class<T> clazz)
      throws JsonParseException, JsonMappingException, IOException {

      ObjectMapper objectMapper = new ObjectMapper();
      return objectMapper.readValue(json, clazz);
   }
}

public class AppControllerTest extends BaseTest {

    @MockBean
    private IIdmsService service;

    private static final String URI = "/myapi/myApp";


   @Override
   @Before
   public void setUp() {
      super.setUp();
   }

   @Test
   public void testGet() throws Exception {
       AppEntity entity = new AppEntity();
      List<AppEntity> dataList = new ArrayList<AppEntity>();
      AppResponse<AppEntity> dataResponse = new AppResponse<AppEntity>();
      entity.setId(1);
      entity.setCreated_at("2020-02-21 17:01:38.717863");
      entity.setCreated_by(“Abhinav Kr”);
      entity.setModified_at("2020-02-24 17:01:38.717863");
      entity.setModified_by(“Jyoti”);
            dataList.add(entity);

      dataResponse.setData(dataList);

      Mockito.when(service.getApp()).thenReturn(dataList);

      RequestBuilder requestBuilder =  MockMvcRequestBuilders.get(URI)
                 .accept(MediaType.APPLICATION_JSON);

        MvcResult mvcResult = mvc.perform(requestBuilder).andReturn();
        MockHttpServletResponse response = mvcResult.getResponse();

        String expectedJson = this.mapToJson(dataResponse);
        String outputInJson = mvcResult.getResponse().getContentAsString();

        assertEquals(HttpStatus.OK.value(), response.getStatus());
        assertEquals(expectedJson, outputInJson);
   }

   @Test
   public void testCreate() throws Exception {

       AppRequest request = new AppRequest();
       request.createdBy = 1;
       request.AppFullName = “My App”;
       request.appTimezone = “India”;

       String inputInJson = this.mapToJson(request);
       Mockito.doNothing().when(service).createApp(Mockito.any(AppRequest.class));
       service.createApp(request);
       Mockito.verify(service, Mockito.times(1)).createApp(request);

       RequestBuilder requestBuilder =  MockMvcRequestBuilders.post(URI)
                                                             .accept(MediaType.APPLICATION_JSON).content(inputInJson)
                                                             .contentType(MediaType.APPLICATION_JSON);

       MvcResult mvcResult = mvc.perform(requestBuilder).andReturn();
       MockHttpServletResponse response = mvcResult.getResponse();
       assertEquals(HttpStatus.OK.value(), response.getStatus());

   }

   @Test
   public void testUpdate() throws Exception {

       AppRequest request = new AppRequest();
       request.id = 1;
       request.modifiedBy = 1;
        request.AppFullName = “My App”;
       request.appTimezone = “Bharat”;

       String inputInJson = this.mapToJson(request);
       Mockito.doNothing().when(service).updateApp(Mockito.any(AppRequest.class));
       service.updateApp(request);
       Mockito.verify(service, Mockito.times(1)).updateApp(request);

       RequestBuilder requestBuilder =  MockMvcRequestBuilders.put(URI)
                                                             .accept(MediaType.APPLICATION_JSON).content(inputInJson)
                                                             .contentType(MediaType.APPLICATION_JSON);

       MvcResult mvcResult = mvc.perform(requestBuilder).andReturn();
       MockHttpServletResponse response = mvcResult.getResponse();
       assertEquals(HttpStatus.OK.value(), response.getStatus());

   }

   @Test
   public void testDelete() throws Exception {

       AppRequest request = new AppRequest();
       request.id = 1;

       String inputInJson = this.mapToJson(request);
       Mockito.doNothing().when(service).deleteApp(Mockito.any(Integer.class));
       service.deleteApp(request.id);
       Mockito.verify(service, Mockito.times(1)).deleteApp(request.id);

       RequestBuilder requestBuilder =  MockMvcRequestBuilders.delete(URI)
                                                             .accept(MediaType.APPLICATION_JSON).content(inputInJson)
                                                             .contentType(MediaType.APPLICATION_JSON);

       MvcResult mvcResult = mvc.perform(requestBuilder).andReturn();
       MockHttpServletResponse response = mvcResult.getResponse();
       assertEquals(HttpStatus.OK.value(), response.getStatus());

   }

}

C++: Rounding up to the nearest multiple of a number

To always round up

int alwaysRoundUp(int n, int multiple)
{
    if (n % multiple != 0) {
        n = ((n + multiple) / multiple) * multiple;

        // Another way
        //n = n - n % multiple + multiple;
    }

    return n;
}

alwaysRoundUp(1, 10) -> 10

alwaysRoundUp(5, 10) -> 10

alwaysRoundUp(10, 10) -> 10


To always round down

int alwaysRoundDown(int n, int multiple)
{
    n = (n / multiple) * multiple;

    return n;
}

alwaysRoundDown(1, 10) -> 0

alwaysRoundDown(5, 10) -> 0

alwaysRoundDown(10, 10) -> 10


To round the normal way

int normalRound(int n, int multiple)
{
    n = ((n + multiple/2)/multiple) * multiple;

    return n;
}

normalRound(1, 10) -> 0

normalRound(5, 10) -> 10

normalRound(10, 10) -> 10

Check if application is on its first run

There is no way to know that through the Android API. You have to store some flag by yourself and make it persist either in a SharedPreferenceEditor or using a database.

If you want to base some licence related stuff on this flag, I suggest you use an obfuscated preference editor provided by the LVL library. It's simple and clean.

Regards, Stephane

How to make a function wait until a callback has been called using node.js

Since node 4.8.0 you are able to use the feature of ES6 called generator. You may follow this article for deeper concepts. But basically you can use generators and promises to get this job done. I'm using bluebird to promisify and manage the generator.

Your code should be fine like the example below.

const Promise = require('bluebird');

function* getResponse(query) {
  const r = yield new Promise(resolve => myApi.exec('SomeCommand', resolve);
  return r;
}

Promise.coroutine(getResponse)()
  .then(response => console.log(response));

Eclipse interface icons very small on high resolution screen in Windows 8.1

I struggled with this issue for a little bit too. I noticed a lot of you posted really complicated resolutions but there is a much easier way to do this! Its just a program and you shouldn't have to modify scripts, or install third party tools. The issue is related to High DPI scaling as mentioned above but what I think a lot of you are missing is that you can't directly modify compatibility settings on the launcher itself. The launcher and eclipse are two different programs! You need to browse to the Eclipse.exe and override the High DPI scaling option there. Once set, you can use the launcher as normal. The launcher will hit the executable, launch the eclipse.exe and since you set the compatibility settings on the .exe it will run using those settings. I spent like 10 minutes tracking down where the exe was so if its any help mine was located in: C:\Users\username\AppData\Local\Yatta\Launcher\installations\eclipse-ide-for-java-developers\eclipse.exe

Here is a screen shot of how I set my compatibility settings.

Eclipse.exe compatibility settings

And yes, the icons were super small before adjusting this setting. I tried setting compatibility settings on the launcher itself but it obviously didn't fix the issue. But after setting the override High DPI setting for the eclipse.exe icons are now normal size. Let me know if this works for others!

Read XML file into XmlDocument

XmlDocument doc = new XmlDocument();
   doc.Load("MonFichierXML.xml");

    XmlNode node = doc.SelectSingleNode("Magasin");

    XmlNodeList prop = node.SelectNodes("Items");

    foreach (XmlNode item in prop)
    {
        items Temp = new items();
        Temp.AssignInfo(item);
        lstitems.Add(Temp);
    }

The thread has exited with code 0 (0x0) with no unhandled exception

Executing Linq queries can generate extra threads. When I try to execute code that uses Linq query collection in the immediate window it often refuses to run because not enough threads are available to the debugger.

As others have said, for threads to exit when they are finished is perfectly normal.

How to convert Set<String> to String[]?

I was facing the same situation.

I begin by declaring the structures I need:

Set<String> myKeysInSet = null; String[] myArrayOfString = null;

In my case, I have a JSON object and I need all the keys in this JSON to be stored in an array of strings. Using the GSON library, I use JSON.keySet() to get the keys and move to my Set :

myKeysInSet = json_any.keySet();

With this, I have a Set structure with all the keys, as I needed it. So I just need to the values to my Array of Strings. See the code below:

myArrayOfString = myKeysInSet.toArray(new String[myKeysInSet.size()]);

This was my first answer in StackOverflow. Sorry for any error :D

Installing a pip package from within a Jupyter Notebook not working

In IPython (jupyter) 7.3 and later, there is a magic %pip and %conda command that will install into the current kernel (rather than into the instance of Python that launched the notebook).

%pip install geocoder

In earlier versions, you need to use sys to fix the problem like in the answer by FlyingZebra1

import sys
!{sys.executable} -m pip install geocoder

How do I create directory if it doesn't exist to create a file?

An elegant way to move your file to an nonexistent directory is to create the following extension to native FileInfo class:

public static class FileInfoExtension
{
    //second parameter is need to avoid collision with native MoveTo
    public static void MoveTo(this FileInfo file, string destination, bool autoCreateDirectory) { 

        if (autoCreateDirectory)
        {
            var destinationDirectory = new DirectoryInfo(Path.GetDirectoryName(destination));

            if (!destinationDirectory.Exists)
                destinationDirectory.Create();
        }

        file.MoveTo(destination);
    }
}

Then use brand new MoveTo extension:

 using <namespace of FileInfoExtension>;
 ...
 new FileInfo("some path")
     .MoveTo("target path",true);

Check Methods extension documentation.

What does "Table does not support optimize, doing recreate + analyze instead" mean?

The better option is create a new table copy the rows to the destination table, drop the actual table and rename the newly created table . This method is good for small tables,

dplyr change many data types

From the bottom of the ?mutate_each (at least in dplyr 0.5) it looks like that function, as in @docendo discimus's answer, will be deprecated and replaced with more flexible alternatives mutate_if, mutate_all, and mutate_at. The one most similar to what @hadley mentions in his comment is probably using mutate_at. Note the order of the arguments is reversed, compared to mutate_each, and vars() uses select() like semantics, which I interpret to mean the ?select_helpers functions.

dat %>% mutate_at(vars(starts_with("fac")),funs(factor)) %>%   
  mutate_at(vars(starts_with("dbl")),funs(as.numeric))

But mutate_at can take column numbers instead of a vars() argument, and after reading through this page, and looking at the alternatives, I ended up using mutate_at but with grep to capture many different kinds of column names at once (unless you always have such obvious column names!)

dat %>% mutate_at(grep("^(fac|fctr|fckr)",colnames(.)),funs(factor)) %>%
  mutate_at(grep("^(dbl|num|qty)",colnames(.)),funs(as.numeric))

I was pretty excited about figuring out mutate_at + grep, because now one line can work on lots of columns.

EDIT - now I see matches() in among the select_helpers, which handles regex, so now I like this.

dat %>% mutate_at(vars(matches("fac|fctr|fckr")),funs(factor)) %>%
  mutate_at(vars(matches("dbl|num|qty")),funs(as.numeric))

Another generally-related comment - if you have all your date columns with matchable names, and consistent formats, this is powerful. In my case, this turns all my YYYYMMDD columns, which were read as numbers, into dates.

  mutate_at(vars(matches("_DT$")),funs(as.Date(as.character(.),format="%Y%m%d")))

How to do multiline shell script in Ansible

Adding a space before the EOF delimiter allows to avoid cmd:

- shell: |
    cat <<' EOF'
    This is a test.
    EOF

Are there best practices for (Java) package organization?

I've seen some people promote 'package by feature' over 'package by layer' but I've used quite a few approaches over many years and found 'package by layer' much better than 'package by feature'.

Further to that I have found that a hybrid: 'package by module, layer then feature' strategy works extremely well in practice as it has many advantages of 'package by feature':

  • Promotes creation of reusable frameworks (libraries with both model and UI aspects)
  • Allows plug and play layer implementations - virtually impossible with 'package by feature' because it places layer implementations in same package/directory as model code.
  • Many more...

I explain in depth here: Java Package Name Structure and Organization but my standard package structure is:

revdomain.moduleType.moduleName.layer.[layerImpl].feature.subfeatureN.subfeatureN+1...

Where:

revdomain Reverse domain e.g. com.mycompany

moduleType [app*|framework|util]

moduleName e.g. myAppName if module type is an app or 'finance' if its an accounting framework

layer [model|ui|persistence|security etc.,]

layerImpl eg., wicket, jsp, jpa, jdo, hibernate (Note: not used if layer is model)

feature eg., finance

subfeatureN eg., accounting

subfeatureN+1 eg., depreciation

*Sometimes 'app' left out if moduleType is an application but putting it in there makes the package structure consistent across all module types.

How to convert string to IP address and vice versa

Use inet_ntop() and inet_pton() if you need it other way around. Do not use inet_ntoa(), inet_aton() and similar as they are deprecated and don't support ipv6.

Here is a nice guide with quite a few examples.

// IPv4 demo of inet_ntop() and inet_pton()

struct sockaddr_in sa;
char str[INET_ADDRSTRLEN];

// store this IP address in sa:
inet_pton(AF_INET, "192.0.2.33", &(sa.sin_addr));

// now get it back and print it
inet_ntop(AF_INET, &(sa.sin_addr), str, INET_ADDRSTRLEN);

printf("%s\n", str); // prints "192.0.2.33"