1. package com.lakala.mkst.service;
    3. import java.util.concurrent.locks.Condition;
    4. import java.util.concurrent.locks.ReentrantLock;
    6. public class Main {
    8.     static ReentrantLock lock = new ReentrantLock();
    9.     static Condition one = lock.newCondition();
    10.     static Condition two = lock.newCondition();
    11.     volatile static boolean printNum = true;
    13.     public static void main(String[] args) {
    15.         new Thread(() -> {
    16.             for (int a = 1; a < 27; a++) {
    17.                 lock.lock();
    18.                 try {
    19.                     while (!printNum) {
    20.                         one.await();
    21.                     }
    22.                     System.out.print(a);
    23.                     printNum = false;
    24.                     two.signal();
    25.                 } catch (InterruptedException e) {
    26.                     e.printStackTrace();
    27.                 } finally {
    28.                     lock.unlock();
    29.                 }
    31.             }
    32.         }).start();
    35.         new Thread(() -> {
    36.             for (int a = 65; a <= 90; a++) {
    37.                 lock.lock();
    38.                 try {
    39.                     while (printNum) {
    40.                         two.await();
    41.                     }
    42.                     System.out.print((char) a);
    43.                     printNum = true;
    44.                     one.signal();
    45.                 } catch (InterruptedException e) {
    46.                     e.printStackTrace();
    47.                 } finally {
    48.                     lock.unlock();
    49.                 }
    50.             }
    53.         }).start();
    55.     }
    56. }

    打印结果如下：
    1A2B3C4D5E6F7G8H9I10J11K12L13M14N15O16P17Q18R19S20T21U22V23W24X25Y26Z