java建立线程的四种方式

时间 2019-12-22

标签 java 建立线程四种方式栏目 Java 繁體版

原文原文链接

java建立线程的三种方式java

1. 继承Thread类建立线程类app

[java] view plain copyide

package com.thread;
public class FirstThreadTest extends Thread{
int i = 0;
//重写run方法，run方法的方法体就是现场执行体
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. 经过Runable接口建立线程类spa

[java] view plain copy.net

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,"新线程1").start();
new Thread(rtt,"新线程2").start();
}
}
}
}

3. 经过Callable和FutureTask建立线程线程

   a. 建立Callable接口的实现类，并实现call()方法；
   b. 建立Callable实现类的实例，使用FutureTask类来包装Callable对象，该FutureTask对象封装了该Callback对象的call()方法的返回值；
   c. 使用FutureTask对象做为Thread对象的target建立并启动新线程；对象

d. 调用FutureTask对象的get()方法来得到子线程执行结束后的返回值。blog

[java] view plain copy继承

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,"有返回值的线程");
// thread.start();
for(int i = 0;i < 100;i++)
{
System.out.println(Thread.currentThread().getName()+" 的循环变量i的值"+i);
if(i==20)
{
new Thread(ft,"有返回值的线程").start();
}
}
try
{
System.out.println("子线程的返回值："+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. 经过线程池建立线程接口

[java] view plain copy

/**
*
*/
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("线程" + Thread.currentThread() + " " + i);
}
}
}