谈synchronzied和Thread通信

在线程开发中，常常会遇到资源共享与同步的问题，synchronized就是来解决这个问题的，可是当谈到Thread通信，它就不能全部胜任了，还需要notify、wait等来配合。

public class Demo {

	private String msg = "";
	
	private boolean isend = false;

	public String getMsg() {
		return msg;
	}

	public synchronized void setMsg(String msg) {
		isend = false;
		this.msg += msg;
		System.out.println(this.msg);
		if(this.msg.length()==4){
			notify();
			System.out.println(Thread.currentThread().getName()+ "...好了");
			isend = true;
			try {
				System.out.println(Thread.currentThread().getName()+ "...wait");
				wait();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
			
			System.out.println(Thread.currentThread().getName()+"...notify");
			
		}
	}
	
	public synchronized void checkMsg(){
		if(this.msg.length()==4 || isend){
			this.msg = "";
			System.out.println(Thread.currentThread().getName()+ "...收到");
			notify();
			try {
				System.out.println(Thread.currentThread().getName()+"...wait");
				wait();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}
	
}