Java 中的 线程之间通信函数

如果您知道进程间如何通信，那么您将很容易理解线程之间通信，在开发两个或多个线程交换某些信息的应用程序时，线程间通信非常重要。

有三种简单的方法和一些使线程通信成为可能的小技巧。这三种方法都在下面列出-

这些方法已在对象(Object)中作为 final 方法实现，因此在所有类中都可用。

此示例显示了两个线程如何使用 wait()和 notify()方法进行通信。

class Chat {
   boolean flag = false;

   public synchronized void Question(String msg) {
      if (flag) {
         try {
            wait();
         } catch (InterruptedException e) {
            e.printStackTrace();
         }
      }
      System.out.println(msg);
      flag = true;
      notify();
   }

   public synchronized void Answer(String msg) {
      if (!flag) {
         try {
            wait();
         } catch (InterruptedException e) {
            e.printStackTrace();
         }
      }

      System.out.println(msg);
      flag = false;
      notify();
   }
}

class T1 implements Runnable {
   Chat m;
   String[] s1 = { "Hi", "How are you ?", "I am also doing fine!" };

   public T1(Chat m1) {
      this.m = m1;
      new Thread(this, "Question").start();
   }

   public void run() {
      for (int i = 0; i < s1.length; i++) {
         m.Question(s1[i]);
      }
   }
}

class T2 implements Runnable {
   Chat m;
   String[] s2 = { "Hi", "I am good, what about you?", "Great!" };

   public T2(Chat m2) {
      this.m = m2;
      new Thread(this, "Answer").start();
   }

   public void run() {
      for (int i = 0; i < s2.length; i++) {
         m.Answer(s2[i]);
      }
   }
}
public class TestThread {
   public static void main(String[] args) {
      Chat m = new Chat();
      new T1(m);
      new T2(m);
   }
}

编译并执行上述程序后，将产生以下输出-

Hi
Hi
How are you ?
I am good, what about you?
I am also doing fine!
Great!