爪哇咖啡屋 : [分享]Java 取得現在的日期、時間

import java.util.Calendar;
import java.text.SimpleDateFormat;

public static final String DATE_FORMAT_NOW = "yyyy-MM-dd HH:mm:ss";

public static String now() {
			 Calendar tmpCal = Calendar.getInstance();
			 SimpleDateFormat tmpSDF = new SimpleDateFormat(DATE_FORMAT_NOW);
			 return tmpSDF.format(tmpCal.getTime();
}

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(Calendar.getInstance().getTime());

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
System.out.println(dateFormat.format(date));

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println(dateFormat.format(cal.getTime()));

Date date = new Date();

LocalDateTime.now()

ZonedDateTime.now()

System.out.println(ZonedDateTime.now().format(DateTimeFormatter.RFC_1123_DATE_TIME))

    // 2015/09/27 15:07:53
    System.out.println( new SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(Calendar.getInstance().getTime()) );

    // 15:07:53
    System.out.println( new SimpleDateFormat("HH:mm:ss").format(Calendar.getInstance().getTime()) );

    // 09/28/2015
    System.out.println(new SimpleDateFormat("MM/dd/yyyy").format(Calendar.getInstance().getTime()));

    // 20150928_161823
    System.out.println( new SimpleDateFormat("yyyyMMdd_HHmmss").format(Calendar.getInstance().getTime()) );

    // Mon Sep 28 16:24:28 CEST 2015
    System.out.println( Calendar.getInstance().getTime() );

    // Mon Sep 28 16:24:51 CEST 2015
    System.out.println( new Date(System.currentTimeMillis()) );

    // Mon Sep 28
    System.out.println( new Date().toString().substring(0, 10) );

    // 2015-09-28
    System.out.println( new java.sql.Date(System.currentTimeMillis()) );

    // 14:32:26
    Date d = new Date();
    System.out.println( (d.getTime() / 1000 / 60 / 60) % 24 + ":" + (d.getTime() / 1000 / 60) % 60 + ":" + (d.getTime() / 1000) % 60 );

    // 2015-09-28 17:12:35.584
    System.out.println( new Timestamp(System.currentTimeMillis()) );

    // Java 8

    // 2015-09-28T16:16:23.308+02:00[Europe/Belgrade]
    System.out.println( ZonedDateTime.now() );

    // Mon, 28 Sep 2015 16:16:23 +0200
    System.out.println( ZonedDateTime.now().format(DateTimeFormatter.RFC_1123_DATE_TIME) );

    // 2015-09-28
    System.out.println( LocalDate.now(ZoneId.of("Europe/Paris")) ); // rest zones id in ZoneId class

    // 16
    System.out.println( LocalTime.now().getHour() );

    // 2015-09-28T16:16:23.315
    System.out.println( LocalDateTime.now() );

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(Calendar.getInstance().getTime());
System.out.println(timeStamp );

Date d = new Date(System.currentTimeMillis());
System.out.print(d);

java.util.Date date = new java.util.Date();

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println(dateFormat.format(cal.getTime())); //2014/08/06 16:00:22

import java.util.Date;
class Demostration{
 public static void main(String[]args){
  Date date=new Date(); // date object
  System.out.println(date); // try to print the date object
 }
}

import java.util.Date;
public class Main {
    public static void main(String[]args){
        Date date =new Date();
        long timeInMilliSeconds=date.getTime();
        System.out.println(timeInMilliSeconds);
    }
}

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
class Demostration{
 public static void main(String[]args){
  Date date=new Date();
  DateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd");
  String formattedDate=dateFormat.format(date);
  System.out.println(formattedDate);
 }
}

import java.util.Calendar;
class Demostration{
 public static void main(String[]args){
  Calendar calendar=Calendar.getInstance();
  System.out.println(calendar.getTime());
 }
}

SimpleDateFormat sdf = new SimpleDateFormat("yyyy:MM:dd::HH:mm:ss");
System.out.println(sdf.format(System.currentTimeMillis()));

Instant.now()

ZonedDateTime.now( ZoneId.of( "America/Montreal" ) )

Instant instant = Instant.now();

ZoneId z = ZoneId.of( "America/Montreal" );
ZonedDateTime zdt = instant.atZone( z );

ZonedDateTime zdt = ZonedDateTime.now( z );

ZonedDateTime do_Not_Do_This = ZonedDateTime.now(); // BAD - Never rely implicitly on the current default time zone.

Instant instant = zdt.toInstant();

ZoneId z = ZoneId.of( "America/Montreal" );
LocalDate today = LocalDate.now( z );  // Always pass a time zone.

    String output = myLocalDate.toString();  // 2016-09-23

String output = zdt.toString();  // 2016-09-23T12:34:56.789+03:00[America/Montreal]

import java.util.*;

import java.text.*;

public class DateDemo { public static void main(String args[]) {

  Date dNow = new Date( );
  SimpleDateFormat ft =
  new SimpleDateFormat ("E yyyy.MM.dd 'at' hh:mm:ss a zzz");

  System.out.println("Current Date: " + ft.format(dNow));

} }

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
System.out.println(dateFormat.format(date)); //2014/08/06 15:59:48

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println(dateFormat.format(cal.getTime())); //2014/08/06 16:00:22

GetCurrentDateTime.java

package com.mkyong;

import java.util.Date;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;

public class GetCurrentDateTime {
  public static void main(String[] args) {

	   DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
	   //get current date time with Date()
	   Date date = new Date();
	   System.out.println(dateFormat.format(date));

	   //get current date time with Calendar()
	   Calendar cal = Calendar.getInstance();
	   System.out.println(dateFormat.format(cal.getTime()));

  }
}

2014/08/06 16:06:54
2014/08/06 16:06:54