通过创建Thread对象来创建一个新的线程,Thread构造方法中需要传入一个Runnable接口的实现(其实就是编写要在另一个线程执行的内容逻辑)同时Runnable只有一个未实现方法,因此可以直接使用lambda表达式:

@FunctionalInterface
public interface Runnable {
    /**
     * When an object implementing interface <code>Runnable</code> is used
     * to create a thread, starting the thread causes the object's
     * <code>run</code> method to be called in that separately executing
     * thread.
     * <p>
     * The general contract of the method <code>run</code> is that it may
     * take any action whatsoever.
     *
     * @see     java.lang.Thread#run()
     */
    public abstract void run();
}

创建好后通过 start() 来运行线程:

public static void main(String[] args) {
    Thread t = new Thread(() -> {    //直接编写逻辑
        System.out.println("我是另一个线程!");
    });
    t.start();   //调用此方法来开始执行此线程
}