Java Date & Time Examples : How To Convert Date To String

Intro

This examples will demonstrates how to convert a date object into string format. It is very quite simple, you can use SimpleDateFormat.format() method to format a date object into specify format.

Examples

package com.freesamplecode.java.datetime;

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

public class ConvertDateToStringDemo {
 public static void main(String[] args){
  
  //get today
  Date today = Calendar.getInstance().getTime();
  
  //create a simple date format object to specify string format
  SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy hh.mm.ss");
  
  //display today in string format
  System.out.println("Today is : "+sdf.format(today));
 }
}

Output

Today is : 31/03/2016 05.58.21

Screenshot

Java Date And Time Examples : How To Compare Two Date Using compareTo Method

Intro

This examples, will demonstrates how to compare two dates using Date.compareTo() method.

Examples

package com.freesamplecode.java.datetime;

import java.util.Date;

public class CompareTwoDateDemo {
 public static void main(String[] args){
  
  //first date object
  Date date1 = new Date();
  
  //sleep 1000 ms before creating second date object
  try{
   Thread.sleep(1000);
  }catch(Exception e){
   e.printStackTrace();
  };
  
  //second date object
  Date date2 = new Date();
  
  int result = date1.compareTo(date2);
  
  System.out.println("First Date :"+date1);
  System.out.println("Second Date :"+date2);
  
  if(result > 0){
   System.out.println("First Date is after Second Date");
  }else if(result < 0){
   System.out.println("First Date is before Second Date");
  }else{
   System.out.println("Both dates are equal");
  }
 }
}

Output

Java Date And Time Examples : Simple Date Example

Intro

This examples, will demonstrates how to use java.util.Date class to display current date.

Examples

package com.freesamplecode.java.datetime;

import java.util.Date;

public class SimpleDateDemo {
 public static void main(String[] args){
  
  //create object date
  
  Date today = new Date();
  
  System.out.println("Today is : "+today);
 }
}

Output

Java Date And Time Examples : How To Display Day Of The Week Using Calendar Class

Intro

This articles, will demonstrates how to display day of the week using java.util.Calendar class.

Examples

package com.freesamplecode.java.datetime;

import java.util.Calendar;

public class GetDayOfWeekDemo {
	public static void main(String[] args){
		Calendar calendar = Calendar.getInstance();
		
		System.out.println("Current Date (mm-dd-yyyy): "+calendar.get(Calendar.MONTH+1)
				+ "-"+calendar.get(Calendar.DATE) + "-"+calendar.get(Calendar.YEAR));
		
		// create an array day of weeks
		String[] dayOfWeeks = {"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};
		
		System.out.println("Current Day is : "+dayOfWeeks[calendar.get(Calendar.DAY_OF_WEEK)-1]);
		
	}
}

Output

Current Date (mm-dd-yyyy): 11-13-2016
Current Day is : Sunday

Screenshot

Java Date And Time Examples : How To Convert Date Into Milliseconds

Intro

This examples will show how to convert a date into milliseconds. To convert a date into miliseconds, you can use the getTime() method of the java.util.Date class.

Examples

package com.freesamplecode.java.datetime;

import java.util.Date;

public class ConvertDateMillisecodDemo {
	public static void main(String[] args){
		Date date = new Date();
		
		System.out.println("Current Date is : "+date);
		System.out.println("Current Date in millisecond : "+date.getTime());
	}
}

Output

Current Date is : Sun Mar 13 06:49:57 ICT 2016
Current Date in millisecond : 1457826597127

Screenshot

Java Copy File Example

Example

package com.freesamplecode.java.io;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class CopyFileDemo {
 public static void main(String[] args) throws IOException{
  try {
   
   // source file
   FileInputStream fis = new FileInputStream("D:/ngoprek/FREESAMPLECODE/src/com/freesamplecode/java/io/test.txt");
   
   //destination file
   FileOutputStream fos = new FileOutputStream("D:/ngoprek/FREESAMPLECODE/src/com/freesamplecode/java/io/testcopy.txt");
   byte[] buf = new byte[1024];
   
   int i = 0;
   
   while((i = fis.read(buf)) != -1){
    fos.write(buf, 0, i);
   }
   
   fis.close();
   fos.close();
   
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  }
 }
}

Get Current Time Java Example

Example

package com.freesamplecode.java.datetime;

import java.util.Calendar;
import java.util.Date;

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

  // first way
  long currentTimeInMillis = System.currentTimeMillis();
  Date today = new Date(currentTimeInMillis);
  System.out.println("Today is " + today);

  // second way
  Calendar cal = Calendar.getInstance();
  today = cal.getTime();
  System.out.println("Today is " + today);
 }
}

Output

Today is Mon Mar 07 17:45:35 ICT 2016
Today is Mon Mar 07 17:45:35 ICT 2016