Java多线程同步工具—Lock和Synchronized实例演示

原创小鱼儿 2024-11-21 17:15 25阅读 0赞

在Java中，多线程同步主要通过两种手段：Lock（锁）接口和synchronized关键字。

1. Lock接口示例：
```java
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class LockDemo {
    private Lock lock = new ReentrantLock();

public void threadSafeMethod() {
        // 使用lock获取锁，确保线程安全
        lock.lock();
        try {
            // 在锁保护的范围内执行操作
            System.out.println("Thread-safe method is executing.");
        } finally {
            // 无论是否发生异常，都需要解锁
            lock.unlock();
        }
    }

public static void main(String[] args) {
        LockDemo demo = new LockDemo();
        Thread thread1 = new Thread(demo::threadSafeMethod));
        Thread thread2 = new Thread(demo::threadSafeMethod));

thread1.start(); // 启动线程1
        thread2.start(); // 同理启动线程2

// 等待所有线程执行完毕
        try {
            thread1.join();
            thread2.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}
```
2. synchronized关键字示例：
```java
public class SynchronizedDemo {
    private Object lock = new Object();

public void synchronizedMethod() {
        synchronized(lock) { // 获取对象锁
            System.out.println("Synchronized method is executing.");
        }}
    }

public static void main(String[] args) {
        SynchronizedDemo demo = new SynchronizedDemo();
        Thread thread1 = new Thread(demo::synchronizedMethod));

thread1.start(); // 启动线程1

try {
            thread1.join(); // 等待线程执行完毕
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}
```
以上两个示例展示了如何在Java多线程中使用Lock和synchronized关键字进行同步控制。