JAVA多线程实现-实现Callable接口

  1. 实现Callable接口
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public class ImplementsCallable implements Callable<Integer> {}
  1. 重写接口call()方法,即线程执行内容。
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    @Override
    public Integer call() throws Exception {
Thread.currentThread().setName("Thread in Callable");
System.out.println(Thread.currentThread().getName() + " i = " + i);
return null;
    }
  1. 通过创建FutureTask来执行给定的Callable
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         Callable<Integer> oneCallable = new ImplementsCallable();
//Creates a FutureTask that will, upon running, execute the given Callable.
FutureTask<Integer> oneTask = new FutureTask<>(oneCallable);
//注释:FutureTask<Integer>是一个包装器,它通过接受Callable<Integer>来创建,它同时实现了Future和Runnable接口。
  1. 通过new Thread(oneTask)创建线程对象。通过start()方法启动线程。
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        //由FutureTask<Integer>创建一个Thread对象:
Thread oneThread = new Thread(oneTask);
oneThread.start();

完整代码:

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import java.util.concurrent.Callable;
import java.util.concurrent.FutureTask;

public class ImplementsCallable implements Callable<Integer>{
//尖括号中也可以是其他任意类
public static int i = 0;

public static void main(String[] args) {
Thread.currentThread().setName("Thread main");

Callable<Integer> oneCallable = new ImplementsCallable();
//Creates a FutureTask that will, upon running, execute the given Callable.
FutureTask<Integer> oneTask = new FutureTask<>(oneCallable);
//注释:FutureTask<Integer>是一个包装器,它通过接受Callable<Integer>来创建,它同时实现了Future和Runnable接口。

//由FutureTask<Integer>创建一个Thread对象:
Thread oneThread = new Thread(oneTask);
oneThread.start();
print();



}

@Override
public Integer call() throws Exception {
Thread.currentThread().setName("Thread in Callable");
System.out.println(Thread.currentThread().getName() + " i = " + i);
return null;
}

public static void print() {
i=0;
for (i = 0; i < 10; i++) {
System.out.println(Thread.currentThread().getName() + ":" + i);
}
}

}