java 删除与新增使用synchronized 给出示例

Synchronized 可以用来保证多线程环境下的安全，比如：

public class Test {
public static void main(String[] args) {
Test test = new Test();

// 创建一个锁对象
Object lock = new Object();

// 创建线程1
Thread thread1 = new Thread(new Runnable() {
@Override
public void run() {
synchronized (lock) {
test.delete();
}
}
});

// 创建线程2
Thread thread2 = new Thread(new Runnable() {
@Override
public void run() {
synchronized (lock) {
test.add();
}
}
});

// 启动线程
thread1.start();
thread2.start();
}

public void delete() {
System.out.println("删除操作");
}

public void add() {
System.out.println("新增操作");
}
}