在学同步时候练习用的
目的是:pro put 0
con get 0
pro put 1
con get 1
...
但是做出来后发现运行结果是随机的~虽然有时候能对上
求教错在哪里?
我怀疑两个synchronized方法是不是用的一个this的锁
但是我看不出怎么改
求教求教
代码如下:
public class Wait
{
public static void main(String[] args)
{
Queue q = new Queue();
Producer pro = new Producer(q);
Consumer con = new Consumer(q);
pro.start();
con.start();
}
}
class Queue
{
int value;
boolean full = false;
public synchronized void input(int i)
{
if(!full)
{
value=i;
full=true;
notify();
}
else
{
try
{
wait();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
public synchronized int output()
{
if(!full)
{
try
{
wait();
}
catch(Exception e)
{
e.printStackTrace();
}
}
else
{
full = false;
notify();
}
return value;
}
}
class Producer extends Thread
{
Queue q;
Producer(Queue q)
{
this.q = q;
}
public void run()
{
for(int i=0;i<10;i++)
{
q.input(i);
System.out.println("Producer input "+i);
}
}
}
class Consumer extends Thread
{
Queue q;
Consumer(Queue q)
{
this.q = q;
}
public void run()
{
while(true)
{
System.out.println("Consumer get "+q.output());
}
}
}
------解决方案--------------------
- Java code
public class Wait { public static void main(String[] args) { Queue q = new Queue(); Producer pro = new Producer(q); Consumer con = new Consumer(q); pro.start(); con.start(); }}class Queue { int value; boolean full = false; public synchronized void input(int i) { if (!full) { value = i; full = true; notify(); } else { try { wait(); } catch (Exception e) { e.printStackTrace(); } } } public synchronized int output() { if (!full) { try { wait(); } catch (Exception e) { e.printStackTrace(); } } else { full = false; notify(); } return value; }}class Producer extends Thread { Queue q; Producer(Queue q) { this.q = q; } public void run() { for (int i = 0; i < 10; i++) { synchronized (this) { while (q.full == true); q.input(i); System.out.println("Producer input " + i); } } }}class Consumer extends Thread { Queue q; Consumer(Queue q) { this.q = q; } public void run() { while (true) { synchronized (this) { while (q.full == false) ; int temp = q.output();//这里顺便将值保存起来，以便退出这个线程,否则你的CPU很生气 System.out.println("Consumer get " + temp); if(temp >=9) System.exit(0); } } }}