java多线程的四种实现方式

1. 继承Thread类，重写run方法
2. 实现Runnable接口，实现run方法
3. 实现Callable接口，重写call方法，利用FutureTask可以获取线程返回值
4. 使用Executor框架创建线程池

1. 继承Thread类，重写run方法

/** * 继承Thread类，重写run方法 * * @Author: zq980328 * @Create: 2022/3/22 14:50 */public class ThreadTest extends Thread {    @Override    public void run() { System.out.println("run===" + Thread.currentThread().getId()); super.run();    }    public static void main(String[] args) { for (int i = 0; i < 10; i++) {     ThreadTest threadTest = new ThreadTest();     threadTest.start(); }    }}

2. 实现Runnable接口，实现run方法

/** * 实现Runnable接口，实现run方法 * * @Author: zq980328 * @Create: 2022/3/22 14:50 */public class RunnableTest implements Runnable {    @Override    public void run() { System.out.println("run===" + Thread.currentThread().getId());    }    public static void main(String[] args) { RunnableTest runnableTest = new RunnableTest(); for (int i = 0; i < 10; i++) {     Thread thread = new Thread(runnableTest);     thread.start(); }    }}

Java8 lambda写法

Thread thread = new Thread(() -> {    System.out.println("run===" + Thread.currentThread().getId());});thread.start();

3. 实现Callable接口，重写call方法，利用FutureTask可以获取线程返回值

/** * 实现Callable接口，重写call方法，利用FutureTask可以获取线程返回值 * * @Author: zq980328 * @Create: 2022/3/22 15:13 */public class CallableTest implements Callable {    @Override    public Object call() { System.out.println("run===" + Thread.currentThread().getId()); return "success" + Thread.currentThread().getId();    }    public static void main(String[] args) throws ExecutionException, InterruptedException { CallableTest callableTest = new CallableTest(); for (int i = 0; i < 10; i++) {     FutureTask<Object> future = new FutureTask<Object>(callableTest);     Thread thread = new Thread(future);     thread.start();     // 获取返回值     future.get(); }    }}

4. 使用Executor框架创建线程池

使用ThreadPoolExecutor创建自定义线程池

/** * 使用ThreadPoolExecutor创建自定义线程池 * * @Author: zq980328 * @Create: 2022/3/22 15:33 */public class ExecutorsTest {    public static void main(String[] args) { // ExecutorService executorService = Executors.newCachedThreadPool(); Thread thread = new Thread(() -> {     System.out.println("run===" + Thread.currentThread().getId()); }); for (int i = 0; i < 10; i++) {     executorService.execute(thread);     // executorService.submit可以获取线程返回值     // Future submit = executorService.submit(thread); }    }}

使用Executors工具类创建默认线程池

/** * 使用Executors工具类创建默认线程池 * * @Author: zq980328 * @Create: 2022/3/22 15:33 */public class ExecutorsTest {    public static void main(String[] args) { // 使用Executors工具类创建默认线程池 ExecutorService executorService = Executors.newCachedThreadPool(); Thread thread = new Thread(() -> {     System.out.println("run===" + Thread.currentThread().getId()); }); for (int i = 0; i < 10; i++) {     executorService.execute(thread);     // executorService.submit可以获取线程返回值     // Future submit = executorService.submit(thread); }    }}