參考自：http://blog.csdn.net/longshengguoji/article/details/41126119

java建立執行緒的三種方式

1. 繼承Thread類建立執行緒類

    package com.thread;  
      
    public class FirstThreadTest extends Thread{  
        int i = 0;  
        //重寫run方法，run方法的方法體就是現場執行體  
        public void run()  
        {  
            for(;i<100;i++){  
            System.out.println(getName()+"  "+i);  
              
            }  
        }  
        public static void main(String[] args)  
        {  
            for(int i = 0;i< 100;i++)  
            {  
                System.out.println(Thread.currentThread().getName()+"  : "+i);  
                if(i==20)  
                {  
                    new FirstThreadTest().run();  
                    new FirstThreadTest().run();  
                }  
            }  
        }  
      
    }  
 

2. 通過Runable介面建立執行緒類

    package com.thread;  
      
    public class RunnableThreadTest implements Runnable  
    {  
      
        private int i;  
        public void run()  
        {  
            for(i = 0;i <100;i++)  
            {  
                System.out.println(Thread.currentThread().getName()+" "+i);  
            }  
        }  
        public static void main(String[] args)  
        {  
            for(int i = 0;i < 100;i++)  
            {  
                System.out.println(Thread.currentThread().getName()+" "+i);  
                if(i==20)  
                {  
                    RunnableThreadTest rtt = new RunnableThreadTest();  
                    new Thread(rtt,"新執行緒1").start();  
                    new Thread(rtt,"新執行緒2").start();  
                }  
            }  
      
        }  
      
    }  
 

3. 通過Callable和FutureTask建立執行緒

    d. 呼叫FutureTask物件的get()方法來獲得子執行緒執行結束後的返回值。

package com.demo;

import java.util.concurrent.Callable;  
import java.util.concurrent.ExecutionException;  
import java.util.concurrent.FutureTask;  
  
public class CallableThreadTest implements Callable<Integer>  
{  
  
    public static void main(String[] args)  
    {  
        CallableThreadTest ctt = new CallableThreadTest();  
        FutureTask<Integer> ft = new FutureTask<Integer>(ctt);  
//        Thread thread = new Thread(ft,"有返回值的執行緒");
//        thread.start();
        for(int i = 0;i < 100;i++)  
        {  
            System.out.println(Thread.currentThread().getName()+" 的迴圈變數i的值"+i);  
            if(i==20)  
            {  
                new Thread(ft,"有返回值的執行緒").start();  
            }  
        }  
        try  
        {  
            System.out.println("子執行緒的返回值："+ft.get());  
        } catch (InterruptedException e)  
        {  
            e.printStackTrace();  
        } catch (ExecutionException e)  
        {  
            e.printStackTrace();  
        }  
  
    }  
  
    @Override  
    public Integer call() throws Exception  
    {  
        int i = 0;  
        for(;i<100;i++)  
        {  
            System.out.println(Thread.currentThread().getName()+" "+i);  
        }  
        return i;  
    }  
  
}  
 

4. 通過執行緒池建立執行緒

/**
 * 
 */
package com.demo;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * @author Maggie
 *
 */
public class ThreadPool 
{
	/* POOL_NUM */
	private static int POOL_NUM = 10;
	
	/**
	 * Main function
	 */
	public static void main(String[] args)
	{
		ExecutorService executorService = Executors.newFixedThreadPool(5);
		for(int i = 0; i<POOL_NUM; i++)
		{
			RunnableThread thread = new RunnableThread();
			executorService.execute(thread);
		}
	}
}

class RunnableThread implements Runnable
{
	private int THREAD_NUM = 10;
	public void run()
	{
		for(int i = 0; i<THREAD_NUM; i++)
		{
			System.out.println("執行緒" + Thread.currentThread() + " " + i);
		} 
	}
}