/*
生产者，消费者。
多生产者，多消费者的问题。
if判断标记，只有一次，会导致不该运行的线程运行了。出现了数据错误的情况。
while判断标记，解决了线程获取执行权后，是否要运行！
notify:只能唤醒一个线程，如果本方唤醒了本方，没有意义。而且while判断标记+notify会导致死锁。
notifyAll解决了本方线程一定会唤醒对方线程的问题。
*/
class Resource
{
private String name
;
private int count
= 1
;
private boolean flag
= false;
public synchronized void set
(String name
)//
{
while
(flag
)
try
{this.wait
();}catch
(InterruptedException e
){}// t1 t0
this.name
= name + count
;//烤鸭1 烤鸭2 烤鸭3
count++
;//2 3 4
System.out.println
(Thread.currentThread
().getName
()+
"...生产者..."+this.name
);//生产烤鸭1 生产烤鸭2 生产烤鸭3
flag
= true;
notifyAll
();
}
public synchronized void out
()// t3
{
while
(!flag
)
try
{this.wait
();}catch
(InterruptedException e
){} //t2 t3
System.out.println
(Thread.currentThread
().getName
()+
"...消费者........"+this.name
);//消费烤鸭1
flag
= false;
notifyAll
();
}
}
class Producer implements Runnable
{
private Resource r
;
Producer
(Resource r
)
{
this.r
= r
;
}
public void run
()
{
while
(true
)
{
r.set
("烤鸭");
}
}
}
class Consumer implements Runnable
{
private Resource r
;
Consumer
(Resource r
)
{
this.r
= r
;
}
public void run
()
{
while
(true
)
{
r.out
();
}
}
}
class ProducerConsumerDemo
{
public static void main
(String
[] args
)
{
Resource r
= new Resource
();
Producer pro
= new Producer
(r
);
Consumer con
= new Consumer
(r
);
Thread t0
= new Thread
(pro
);
Thread t1
= new Thread
(pro
);
Thread t2
= new Thread
(con
);
Thread t3
= new Thread
(con
);
t0.start
();
t1.start
();
t2.start
();
t3.start
();
}
}
