多个线程顺序打印问题

今天看到了一道题：
三个线程分别打印A，B，C，要求这三个线程一起运行，打印n次，输出形如“ABCABCABC....”的字符串
由于本人没有开发过关于多线程的项目，所以对线程的了解，更多的偏向于网络资料以及个人理解！
以我的角度来说，线程排序打印，三种方式：
1、用join方法，强行让线程加入运行行列：

Thread t1 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("A");
                } catch (Exception e) {
                     e.printStackTrace();
                }
                
            }
        });
         Thread t2 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("B");
                } catch (Exception e) {
                     e.printStackTrace();
                }
                
            }
        });
         
         Thread t3 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("C");
                } catch (Exception e) {
                    // TODO: handle exception
                }
                
            }
        });
         t1.start();
         t1.join();
         t2.start();
         t2.join();
         t3.start();
         t3.join();

2、借于https://blog.csdn.net/zy90101...，concurrent包里面有个CountDownLatch计数器，这里面有2个方法：c.countDown()：作用是计数器减1，c1.await()，如果计数器暂时没有到0，则阻塞线程。

    CountDownLatch c1 = new CountDownLatch(1);
    CountDownLatch c2 = new CountDownLatch(1);
    CountDownLatch call = new CountDownLatch(3);
    Thread t1 = new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                c2.await();
                System.out.println("A");
                call.countDown();
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    });
    Thread t2 = new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                c1.await();
                System.out.println("B");
                c2.countDown();
                call.countDown();
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    });
    Thread t3 = new Thread(new Runnable() {
        @Override
        public void run() {
            System.out.println("C");
            c1.countDown();
            call.countDown();
        }
    });
    t1.start();
    t2.start();
    t3.start();
    try {
        call.await();
    }catch (Exception e){
        e.printStackTrace();
    }

3、用线程池：

static ExecutorService executors =           Executors.newSingleThreadExecutor();
public static void main(String[] args){
         Thread t1 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("A");
                } catch (Exception e) {
                     e.printStackTrace();
                }
                
            }
        });
         Thread t2 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("B");
                } catch (Exception e) {
                     e.printStackTrace();
                }
                
            }
        });
         
         Thread t3 = new Thread(new Runnable() {
            
            @Override
            public void run() {
                try {
                    System.out.print("C");
                } catch (Exception e) {
                    // TODO: handle exception
                }
                
            }
        });
         for (int i = 0; i < 10; i++) {
             executors.submit(new Thread(t1));
             executors.submit(new Thread(t2));
             executors.submit(new Thread(t3));
        }
             
             executors.shutdown();

总结：不做循环打印的话，三种都可以实现！唯独第三种实现了循环打印，我实力有限，而且借此机会对线程的运用多了一些理解！只是个人记录，做备忘用而已