What is the use of Thread.sleep() method in Java?

Thread.sleep() :

The java.lang.Thread.sleep(long millis) method causes the currently executing thread to sleep for the specified number of milliseconds, subject to the precision and accuracy of system timers and schedulers.

Declaration

Following is the declaration for java.lang.Thread.sleep() method

public static void sleep(long millis) throws InterruptedException

Parameters

millis − This is the length of time to sleep in milliseconds.

Return Value

This method does not return any value.

Exception

InterruptedException − if any thread has interrupted the current thread. The interrupted status of the current thread is cleared when this exception is thrown.

Example

The following example shows the usage of java.lang.Thread.sleep() method.

import java.lang.*;

public class ThreadDemo implements Runnable {

Thread t;

public void run() {
 for (int i = 10; i < 13; i++) {

 System.out.println(Thread.currentThread().getName() + " " + i);
 try {
 // thread to sleep for 1000 milliseconds
 Thread.sleep(1000);
 } catch (Exception e) {
 System.out.println(e);
 }
 }
 }

public static void main(String[] args) throws Exception {
 Thread t = new Thread(new ThreadDemo());
 // this will call run() function
 t.start();

 Thread t2 = new Thread(new ThreadDemo());
 // this will call run() function
 t2.start();
 }
}

Let us compile and run the above program, this will produce the following result

Thread-0 10
Thread-1 10
Thread-0 11
Thread-1 11
Thread-0 12
Thread-1 12