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我一直在研究PC问题以了解Java同步和线程间通信。使用代码在底部，产量为使用java同步了解生产者 - 使用者
Producer produced-0
Producer produced-1
Producer produced-2
Consumer consumed-0
Consumer consumed-1
Consumer consumed-2
Producer produced-3
Producer produced-4
Producer produced-5
Consumer consumed-3
Consumer consumed-4
但不宜输出是类似如下
Producer produced-0
Consumer consumed-0
Producer produced-1
Consumer consumed-1
Producer produced-2
Consumer consumed-2
Producer produced-3
我希望这样的输出，因为我的理解是，消费者被通知当方法终止时，生产方法释放后立即生成的值将被锁定。结果等待的用户块，进入同步状态获取锁定消耗产生的值，同时生成器方法被阻塞。该锁在由生产者线程获取的消耗方法的末尾被释放，该线程由于同步而被阻塞，并且随着每个方法由于获取的锁而被阻塞，周期继续。
请让我知道我误解了什么？由于
package MultiThreading;
//Java program to implement solution of producer
//consumer problem.
import java.util.LinkedList;
public class PCExample2
{
public static void main(String[] args)
throws InterruptedException
{
// Object of a class that has both produce()
// and consume() methods
final PC pc = new PC();
// Create producer thread
Thread t1 = new Thread(new Runnable()
{
@Override
public void run()
{
try
{
while (true) {
pc.produce();
}
}
catch(InterruptedException e)
{
e.printStackTrace();
}
}
});
// Create consumer thread
Thread t2 = new Thread(new Runnable()
{
@Override
public void run()
{
try
{
while (true) {
pc.consume();
}
}
catch(InterruptedException e)
{
e.printStackTrace();
}
}
});
// Start both threads
t1.start();
t2.start();
// t1 finishes before t2
t1.join();
t2.join();
}
// This class has a list, producer (adds items to list
// and consumber (removes items).
public static class PC
{
// Create a list shared by producer and consumer
// Size of list is 2.
LinkedList<Integer> list = new LinkedList<>();
int capacity = 12;
int value = 0;
// Function called by producer thread
public void produce() throws InterruptedException
{
synchronized (this)
{
// producer thread waits while list
// is full
while (list.size()==capacity)
wait();
System.out.println("Producer produced-"
+ value);
// to insert the jobs in the list
list.add(value++);
// notifies the consumer thread that
// now it can start consuming
notify();
// makes the working of program easier
// to understand
Thread.sleep(1000);
}
}
// Function called by consumer thread
public void consume() throws InterruptedException
{
synchronized (this)
{
// consumer thread waits while list
// is empty
while (list.size()==0)
wait();
//to retrive the ifrst job in the list
int val = list.removeFirst();
System.out.println("Consumer consumed-"
+ val);
// Wake up producer thread
notify();
// and sleep
Thread.sleep(1000);
}
}
}
}
看看：https：//stackoverflow.com/questions/2332537/producer-consumer-threads-using-a-queue/37767243#37767243 –
你可能想看看会发生什么，如果你移动这些线程。睡眠（1000）'调出'同步的'块。 –