love3400windµÄblog

import java.lang.Thread;
import java.lang.InterruptedException;
import java.util.concurrent.Semaphore;
public class Main{
	private static Semaphore A = new Semaphore(1);
	private static Semaphore B = new Semaphore(1);
	private static Semaphore C = new Semaphore(1);

	static class ThreadA extends Thread{
		public void run() {
			for (int i=0; i<10; i++){
				try{
					A.acquire();
				} catch(InterruptedException e) {}
				System.out.print("A");
				B.release();
			}
		}
	}

	static class ThreadB extends Thread {
		public void run() {
			for(int i=0; i<10; i++) {
				try {
					B.acquire();
				} catch (InterruptedException e) {

				}
				System.out.print("B");
				C.release();
			}
		}
	}

	static class ThreadC extends Thread{
		public void run() {
			for (int i=0; i<10; i++) {
				try {
					C.acquire();
				} catch(InterruptedException e) {}
				System.out.println("C");
				A.release();
			}
		}
	}

	public static void main(String [] args) throws InterruptedException{
		B.acquire();
		C.acquire();

		new ThreadA().start();
		new ThreadB().start();
		new ThreadC().start();
		
	}
	
}