CreateThread.md

layout	title	parent	nav_order
default	Create Thread	Multithreading	3

How to create thread

There are two ways to create a thread:

1- By extending Thread class

2- By implementing Runnable interface.

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Thread class:

Thread class provide constructors and methods to create and perform operations on a thread.Thread class extends Object class and implements Runnable interface.

Commonly used Constructors of Thread class:

Thread()
Thread(String name)
Thread(Runnable r)
Thread(Runnable r,String name)

Commonly used methods of Thread class:

1- public void run(): is used to perform action for a thread.
2- public void start(): starts the execution of the thread.JVM calls the run() method on the thread.
3- public void sleep(long miliseconds): Causes the currently executing thread to sleep (temporarily cease execution) for the specified number of milliseconds.
4- public void join(): waits for a thread to die.
5- public void join(long miliseconds): waits for a thread to die for the specified miliseconds.
6- public int getPriority(): returns the priority of the thread.
7- public int setPriority(int priority): changes the priority of the thread.
8- public String getName(): returns the name of the thread.
9- public void setName(String name): changes the name of the thread.
10- public Thread currentThread(): returns the reference of currently executing thread.
11- public int getId(): returns the id of the thread.
12- public Thread.State getState(): returns the state of the thread.
13- public boolean isAlive(): tests if the thread is alive.
14- public void yield(): causes the currently executing thread object to temporarily pause and allow other threads to execute.
15- public void suspend(): is used to suspend the thread(depricated).
16- public void resume(): is used to resume the suspended thread(depricated).
17- public void stop(): is used to stop the thread(depricated).
18- public boolean isDaemon(): tests if the thread is a daemon thread.
19- public void setDaemon(boolean b): marks the thread as daemon or user thread.
20- public void interrupt(): interrupts the thread.
21- public boolean isInterrupted(): tests if the thread has been interrupted.
22- public static boolean interrupted(): tests if the current thread has been interrupted.

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Runnable interface:

The Runnable interface should be implemented by any class whose instances are intended to be executed by a thread. Runnable interface have only one method named run().

       public void run(): is used to perform action for a thread.

Starting a thread:

   start() method of Thread class is used to start a newly created thread. It performs following tasks:
   
       A new thread starts(with new callstack).
       The thread moves from New state to the Runnable state.
       When the thread gets a chance to execute, its target run() method will run.

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1) Java Thread Example by extending Thread class

    class Multi extends Thread{  
    public void run(){  
    System.out.println("thread is running...");  
    }  
    public static void main(String args[]){  
    Multi t1=new Multi();  
    t1.start();  
     }  
    }  

Output

Output:thread is running...

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2) Java Thread Example by implementing Runnable interface

    class Multi3 implements Runnable{  
    public void run(){  
    System.out.println("thread is running...");  
    }  
      
    public static void main(String args[]){  
    Multi3 m1=new Multi3();  
    Thread t1 =new Thread(m1);  
    t1.start();  
     }  
    }  

Output

Output:thread is running...