如何使用synchronized修饰符定义Java中的函数

public synchronized void synchronizedMethod() {
    // 方法代码
}

public class Counter {
    private int counter = 0;

    public void increment() {
        counter++;
    }
}

public class TestCounter {

    public static void main(String[] args) {
        Counter counter = new Counter();

        // 创建并启动 10 个线程
        for (int i = 0; i < 10; i++) {
            new Thread(() -> {
                for (int j = 0; j < 1000; j++) {
                    counter.increment();
                }
            }).start();
        }

        // 等待所有线程完成
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        // 打印最终 counter 值
        System.out.println("最终 counter 值：" + counter.counter);
    }
}

public class Counter {

    private int counter = 0;

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

最终 counter 值：10000