How to initialize a variable of date type in java

Question

import java util Date  Date firstDate     I don t know how to intialize the firstDate for example for String you say   String line1  First line     but what is the format for date can you give me an example

User · Answer

To parse a Date from a String you can choose which format you would like it to have. For example:

public Date StringToDate(String s){

    Date result = null;
    try{
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        result  = dateFormat.parse(s);
    }

    catch(ParseException e){
        e.printStackTrace();

    }
    return result ;
}

If you would like to use this method now, you will have to use something like this

Date date = StringToDate("2015-12-06 17:03:00");

For more explanation you should check out http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

User · Answer

To initialize to current date  you could do something like   Date firstDate   new Date      To get it from String  you could use SimpleDateFormat like   String dateInString    10-Jan-2016   SimpleDateFormat formatter   new SimpleDateFormat  dd-MMM-yyyy    try       Date date   formatter parse dateInString       System out println date       System out println formatter format date      catch  ParseException e          handle exception if date is not in  dd-MMM-yyyy  format

User · Answer

Here s the Javadoc in Oracle s website for the Date class  https   docs oracle com javase 8 docs api java util Date html If you scroll down to  Constructor Summary   you ll see the different options for how a Date object can be instantiated  Like all objects in Java  you create a new one with the following   Date firstDate   new Date ConstructorArgsHere     Now you have a bit of a choice  If you don t pass in any arguments  and just do this   Date firstDate   new Date      it will represent the exact date and time at which you called it  Here are some other constructors you may want to make use of   Date firstDate1   new Date int year  int month  int date   Date firstDate2   new Date int year  int month  int date  int hrs  int min   Date firstDate3   new Date int year  int month  int date  int hrs  int min  int sec

User · Answer

java util Date constructor with parameters like  new Date int year  int month  int date  int hrs  int min   is deprecated and preferably do not use it any more  Oracle docs prefers the way over java util Calendar  So you can set any date and instantiate Date object through the getTime   method   Calendar calendar   Calendar getInstance    calendar set 2018  11  31  59  59  59   Date happyNewYearDate   calendar getTime      Notice that month number starts from 0

User · Answer

tl dr  Use Instant  replacement for java util Date   Instant now       Capture current moment as seen in UTC    If you must have a Date  convert   java util Date from  Instant now        java time  The java util Date  amp   Calendar classes have been supplanted by the java time framework built into Java 8 and later  The new classes are a tremendous improvement  inspired by the successful Joda-Time library   The java time classes tend to use static factory methods rather than constructors for instantiating objects    To get the current moment in UTC time zone   Instant instant   Instant now      To get the current moment in a particular time zone   ZoneId zoneId   ZoneId of   America Montreal     ZonedDateTime zdt   ZonedDateTime now  zoneId      If you must have a java util Date for use with other classes not yet updated for the java time types  convert from Instant   java util Date date   java util Date from  zdt toInstant            About java time  The java time framework is built into Java 8 and later  These classes supplant the troublesome old legacy date-time classes such as java util Date  Calendar   amp  SimpleDateFormat   To learn more  see the Oracle Tutorial  And search Stack Overflow for many examples and explanations  Specification is JSR 310   The Joda-Time project  now in maintenance mode  advises migration to the java time classes   You may exchange java time objects directly with your database  Use a JDBC driver compliant with JDBC 4 2 or later  No need for strings  no need for java sql   classes   Where to obtain the java time classes     Java SE 8  Java SE 9  Java SE 10  Java SE 11  and later  - Part of the standard Java API with a bundled implementation    Java 9 adds some minor features and fixes   Java SE 6 and Java SE 7   Most of the java time functionality is back-ported to Java 6  amp  7 in ThreeTen-Backport   Android   Later versions of Android bundle implementations of the java time classes  For earlier Android   lt 26   the ThreeTenABP project adapts ThreeTen-Backport  mentioned above   See How to use ThreeTenABP        The ThreeTen-Extra project extends java time with additional classes  This project is a proving ground for possible future additions to java time  You may find some useful classes here such as Interval  YearWeek  YearQuarter  and more

[java] How to initialize a variable of date type in java?

Examples related to java

Examples related to date

Examples related to variables