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Creating and Running a Java Thread:

Ways to create a Thread:

You can create a Thread in two ways:

  • By extending the Thread class.
  • By implementing a Runnable Interface.

Thread class:

The Thread class provides constructors and methods to create and perform operations on a thread.

Runnable Interface:

Runnable Interfaces have only one method, named run(). The Runnable Interface should be performed by classes where their instances plan to be executed by a thread. public void run(): is used to perform the action for a Thread.

Starting a thread:

The start() method of a Thread class is used to start a newly created thread. It performs the following tasks:

  • A new thread starts(with their stack).
  • The Thread moves to the Runnable state from New state.
  • The run() method will run when the Thread gets a chance.

Java Thread Example by extending Thread class:

  1. class Multi extends Thread{  
  2. public void run(){  
  3. System.out.println("Extended Thread Class Example: thread is running...");  
  4. }  
  5. public static void main(String args[]){  
  6. Multi threadOne=new Multi();  
  7. threadOne.start();  
  8.  }  
  9. }  
Output:Extended Thread Class Example: thread is running...


Java Thread Example by implementing Runnable interface:

  1. class Multi implements Runnable{  
  2. public void run(){  
  3. System.out.println("Runnable Interface Example: thread is running...");  
  4. }  
  5.   
  6. public static void main(String args[]){  
  7. Multi multiOne=new Multi();  
  8. Thread threadOne =new Thread(multiOne);  
  9. threadOne.start();  
  10.  }  
  11. }  
Output:Runnable Interface Example: thread is running...

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