今天看了一个有BUG的多线程代码，但是怎么看也没看出问题来，高手来解释解释吧.
代码：
import java.util.*;
public class PrintQueue {
private LinkedList<String> queue = new LinkedList<String>();
private final Object lock = new Object();
public void enqueue(String str) {
synchronized (lock) {
queue.addLast(str);
lock.notifyAll();
}
}
public void work() {
String current;
synchronized(lock) {
if (queue.isEmpty()) {
try {
lock.wait();
} catch (InterruptedException e) {
assert (false);
}
}
current = queue.removeFirst();
}
System.out.println(current);
}
public static void main(String[] args) {
final PrintQueue pq = new PrintQueue();
Thread producer1 = new Thread() {
public void run() {
pq.enqueue("anemone");
pq.enqueue("tulip");
pq.enqueue("cyclamen");
}
};
Thread producer2 = new Thread() {
public void run() {
pq.enqueue("iris");
pq.enqueue("narcissus");
pq.enqueue("daffodil");
}
};
Thread consumer1 = new Thread() {
public void run() {
pq.work();
pq.work();
pq.work();
pq.work();
}
};
Thread consumer2 = new Thread() {
public void run() {
pq.work();
pq.work();
}
};
producer1.start();
consumer1.start();
consumer2.start();
producer2.start();
}
}
问题补充
这个是有同步锁的怎么可能两个都进呢？
synchronized(lock)
