线程创建的五种方式

继承Thread，重写run方法，直接new对象.start启动

public class T1 {
    static class MyThread extends Thread{
        @Override
        public void run() {
            System.out.println("MyThread...");
        }
    }

    public static void main(String[] args) {
        new MyThread().start();
    }
}

实现Runnable接口，重写run方法，new出Thread传入对象作为参数，.start启动

public class T2 {
    static class MyRun implements Runnable{
        public void run() {
            System.out.println("MyRun...");
        }
    }

    public static void main(String[] args) {
        new Thread(new MyRun()).start();
    }
}

new出Tread对象，使用lambda表达式，.start启动

public class T3 {
    public static void main(String[] args) {
        new Thread(()-> System.out.println("lambda...")).start();
    }
}

使用线程池ExecutorService，调用execute方法，传入一个Runnable的实现类

public class T4 {
    public static void main(String[] args) {
        ExecutorService service = Executors.newCachedThreadPool();
        service.execute(() -> System.out.println("Executor..."));
        service.shutdown();
    }
}

实现Callable接口，用线程池的submit方法调用
返回值为Future，指定泛型作为线程的返回值类型
不用线程池的情况下，需要用FutureTask套一层作为参数传给Thread

public class T5 {
    static class MyCall implements Callable {
        @Override
        public String call(){
            return "Callable...";
        }
    }

    public static void main(String[] args) throws ExecutionException, InterruptedException {
        ExecutorService service = Executors.newCachedThreadPool();

        Future submit = service.submit(new MyCall());
        System.out.println(submit.get());

        service.shutdown();

        FutureTask task = new FutureTask(new MyCall());
        new Thread(task).start();
    }
}