实战：Java多线程编程实例

原创以你之姓@ 2024-11-12 20:42 6阅读 0赞

Java多线程编程是Java编程中的一个重要部分，它允许程序同时执行多个任务。以下是一些基本的Java多线程编程实例：

###1. 创建线程的两种方式#### 方式一：继承Thread类```javaclass MyThread extends Thread {
 public void run() {
 System.out.println("线程运行中...");
 }
}

public class ThreadExample {
 public static void main(String[] args) {
 MyThread t1 = new MyThread();
t1.start(); //启动线程 }
}
```#### 方式二：实现Runnable接口```javaclass MyRunnable implements Runnable {
 public void run() {
 System.out.println("线程运行中...");
 }
}

public class RunnableExample {
 public static void main(String[] args) {
Thread t1 = new Thread(new MyRunnable());
t1.start(); //启动线程 }
}
```###2.线程同步当多个线程访问共享资源时，需要同步以避免数据不一致。可以使用`synchronized`关键字来实现。

```javaclass Counter {
 private int count =0;

public synchronized void increment() {
 count++;
 }

public synchronized int getCount() {
 return count;
 }
}

class ThreadA extends Thread {
 private Counter counter;

public ThreadA(Counter counter) {
 this.counter = counter;
 }

public void run() {
 for (int i =0; i <1000; i++) {
 counter.increment();
 }
 }
}

public class SynchronizedExample {
 public static void main(String[] args) {
Counter counter = new Counter();
ThreadA t1 = new ThreadA(counter);
ThreadA t2 = new ThreadA(counter);

t1.start();
t2.start();

try {
t1.join();
t2.join();
} catch (InterruptedException e) {
e.printStackTrace();
 }

System.out.println("Final count is " + counter.getCount());
 }
}
```###3.线程通信线程间可以通过`wait()`和`notify()`方法进行通信。

```javaclass Message {
 private String message = "";
 private boolean ready = false;

public synchronized void put(String message) {
 while (ready) {
 try {
 wait();
} catch (InterruptedException e) {
e.printStackTrace();
 }
 }
 this.message = message;
ready = true;
 notify();
 }

public synchronized String get() {
 while (!ready) {
 try {
 wait();
} catch (InterruptedException e) {
e.printStackTrace();
 }
 }
ready = false;
 notify();
 return message;
 }
}

class Producer extends Thread {
 private Message message;

public Producer(Message message) {
 this.message = message;
 }

public void run() {
 for (int i =0; i <10; i++) {
 message.put("Message " + i);
 try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
 }
 }
 }
}

class Consumer extends Thread {
 private Message message;

public Consumer(Message message) {
 this.message = message;
 }

public void run() {
 for (int i =0; i <10; i++) {
String msg = message.get();
 System.out.println(msg);
 try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
 }
 }
 }
}

public class CommunicationExample {
 public static void main(String[] args) {
Message message = new Message();
 Producer producer = new Producer(message);
 Consumer consumer = new Consumer(message);

producer.start();
 consumer.start();
 }
}
```这些实例展示了Java多线程编程的基本方法和一些常见的模式。在实际应用中，你可能需要根据具体需求调整和优化代码。