两个线程交替打印A1B2C3 ... 的几种实现方式

有以下需求:
两个线程,需要打印字母和数字,格式A1B2C3 …
这个问题涉及到线程的等待,唤醒,线程间通信等知识。
下面看看实现代码:

方法1:LockSupport

import java.util.concurrent.locks.LockSupport;

/**
 * @author liming
 * @date 2020/10
 * @description 交替打印 A1B2C3 ...
 */
public class AlternatePrint {
    

    static Thread t1 = null, t2 = null;

    public static void main(String[] args) {
    
        char[] aI = "1234567".toCharArray();
        char[] aC = "ABCDEFG".toCharArray();

        t1 = new Thread(new Runnable() {
    
            @Override
            public void run() {
    
                for (int i = 0; i < aC.length; i++) {
    
                    // 起始先打印一个字母
                    System.out.println(aC[i]);
                    // 打印完唤醒t2打印数字
                    LockSupport.unpark(t2);
                    // 自己阻塞,等待唤醒
                    LockSupport.park();
                }
            }
        });

        t2 = new Thread(new Runnable() {
    
            @Override
            public void run() {
    
                for (int i = 0; i < aI.length; i++) {
    
                    // 起始先阻塞等待
                    LockSupport.park();
                    // 被唤醒后打印数字
                    System.out.println(aI[i]);
                    // 唤醒t1
                    LockSupport.unpark(t1);
                }
            }
        });

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

}

方法2:synchronized

import org.junit.Test;

/**
 * @author liming
 * @date 2020/10/14
 * @description 交替打印 A1B2C3 ...
 */

public class AlternatePrint {
    

    static Thread t1 = null, t2 = null;

    /**
     * 使用 synchronized
     */
    @Test
    public void alternatePrint() {
    
        Object lock = new Object();
        char[] aI = "1234567".toCharArray();
        char[] aC = "ABCDEFG".toCharArray();

        t1 = new Thread(new Runnable() {
    
            @Override
            public void run() {
    
                for (int i = 0; i < aC.length; i++) {
    
                    synchronized (lock) {
    
                        System.out.println(aC[i]);
                        lock.notify();
                        try {
    
                            lock.wait();
                        } catch (InterruptedException e) {
    
                            e.printStackTrace();
                        }
                    }
                }
            }
        });

        t2 = new Thread(new Runnable() {
    
            @Override
            public void run() {
    
                for (int i = 0; i < aI.length; i++) {
    
                    synchronized (lock) {
    
                        System.out.println(aI[i]);
                        lock.notify();
                        try {
    
                            lock.wait();
                        } catch (InterruptedException e) {
    
                            e.printStackTrace();
                        }
                    }
                }
            }
        });

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

}

测试结果:

测试结果

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转载自blog.csdn.net/wandou9527/article/details/109059336