01.线程的三种创建方式与运行

Java 中有三种线程创建方式，分别为实现 Runnable 接口的 run 方法，继承 Thread 类 并重写 run 的方法，使用 FutureTask 方式

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

/**
 * 线程创建与运行
 */
public class Main {

    public static void main(String[] args) throws InterruptedException{
        //外任务与代码没有分离， 当多个线程执行一样的任务时需要 多份任务代码
        MyTread tread = new MyTread(12);
        tread.start();
        System.out.println(Thread.currentThread().getName());//main
        RunableTask runableTask = new RunableTask("21");
        //两个线程共用一个 task 代码逻辑
        new Thread(runableTask).start();
        new Thread(runableTask).start();
        //main
        //I'm a threadThread-0 12
        //I'm a threadThread-1 21
        //I'm a threadThread-2 21

        //创建异步任务
        FutureTask<String> futureTask = new FutureTask<>(new CallerTask());
        //启动线程
        new Thread(futureTask).start();
        try {
            //等待任务执行完，返回结果
            String s = futureTask.get();
            System.out.println(s);//hello
        } catch (ExecutionException e) {
            e.printStackTrace();
        }
    }
    public static class MyTread extends Thread{
        private int age;

        public MyTread(int age) {
            this.age = age;
        }

        @Override
        public void run() {
            //获取当前线程直接使用 this 就可以了
            System.out.println("I'm a thread"+this.getName()+" "+age);//I'm a threadThread-0
        }
    }
    public static class RunableTask implements Runnable{
        private String age;

        public RunableTask(String age) {
            this.age = age;
        }

        @Override
        public void run() {
            System.out.println("I'm a thread"+Thread.currentThread().getName()+" "+age);
        }
    }
    //创建任务类
    public static class CallerTask implements Callable<String>{
        @Override
        public String call() throws Exception {
            return "hello";
        }
    }
}