请教：java多线程问题

   java中有没有类似windows c++编程中的WaitForMultiObjects()的机制，同时等待多个条件，而不是一次等待一个
   比如，java中lock和conditon问题，假如有一个lock，有此lock生成了多个condition,c1,c2,...cn,假如存在两个线程，其中一个线程按如下等待条件，如
    c1.wait();
   c2.wait();
   ...
   cn.wait();

   而另一个线程如下等待条件
    cn.wait();
   ...
   c2.wait();
   c1.wait();
   这样就容易造成死锁，随着condition的增多和线程数量的增多，越是容易造成死锁，有没有个办法，要么可以同时获得c1，c2,...,cn,要么都不获得，即使有个别condition可以获得？

不是很明白你的意思，你可以试试看java.util.concurrent.CountDownLatch是不是满足你的需求

通过Object类里的notify能不能得到解决呢？

好像另外还有关于线程的设计模式，我也记不大清了，希望这个链接可以有所帮助：http://hi.baidu.com/hibydu/blog/item/54e8d61f6bc99362f724e415.html

另处补充一句，那个博客是我刚粟出来的。

一个用CountDownLatch实现的MultiThreadManager
http://www.google.com/codesearch?hl=en&q=+MultiThreadManager+show:ZtTNYs-zcMM:m7pjry2CcK8:xoFWM7LeQ8c&sa=N&cd=1&ct=rc&cs_p=http://jira.codehaus.org/secure/attachment/17644/modules.zip&cs_f=utils/utils-lang-jar/src/main/com/barcoview/mis/utils/lang/thread/MultiThreadManager.java#first
使用示例

 try
 {
    // runables 是要运行的线程列表
    MultiThreadManager manager = new MultiThreadManager( runnables, "MyRunnables-" );
    manager.runAndWait();
 }
 catch( MultiThreadManagerException e )
 {
    MyLogicalException ex = (MyLogicalException)e.getCause();
 }

一下是我的测试程序，如下所示，这个程序很快就会死锁，假如执行add函数的那个线程等待到了c1,c2,c3,c4,而执行rem（）函数的那个线程等到了c7,c6,c5,这时就产生了死锁，我想问的是java中有没有一种机制保证，要么c1,c2,c3,c4,c5,c6,c7全部同时得到，要么就同时放弃，这样就避免了死锁的发生？
public class Test {
private int[] elems = new int[5];
Lock lock1 = new ReentrantLock(true);
Condition c1 = lock1.newCondition();
Condition c2 = lock1.newCondition();
Condition c3 = lock1.newCondition();
Condition c4 = lock1.newCondition();
Condition c5 = lock1.newCondition();
Condition c6 = lock1.newCondition();
Condition c7 = lock1.newCondition();
private int addIndex = 0;
private int remIndex = 0;
private int count = 0;

public void add(int i) {
lock1.lock();
try {
while (elems.length == count) {
try {
c1.await();
c2.await();
c3.await();
c4.await();
c5.await();
c6.await();
c7.await();
} catch (Exception e) {
e.printStackTrace();
}
}
elems[addIndex++] = i;
count++;
addIndex = addIndex % elems.length;
System.out.println(Thread.currentThread().getName()
+ " add  count=" + count);
c1.signal();
c2.signal();
c3.signal();
c4.signal();
c5.signal();
c6.signal();
c7.signal();
} finally {
lock1.unlock();
}
}

public int rem() {
int res = 0;
lock1.lock();
try {
while (0 == count) {
try {
c7.await();
c6.await();
c5.await();
c4.await();
c3.await();
c2.await();
c1.await();

} catch (Exception e) {
e.printStackTrace();
}
}
res = elems[remIndex++];

count--;
remIndex = remIndex % elems.length;
System.out.println(Thread.currentThread().getName()
+ " remove  count=" + count);

c7.signal();
c6.signal();
c5.signal();
c4.signal();
c3.signal();
c2.signal();
c1.signal();

} finally {
lock1.unlock();
}
return res;
}

public void start() {
for (int i = 0; i < 3000; i++) {
Thread t = new Thread(new producer(this));
t.start();
}
for (int i = 0; i < 3; i++) {
Thread t = new Thread(new consumer(this));
t.start();
}
}

/**
* @param args
*/
public static void main(String[] args) {
Test test = new Test();
test.start();
}
}

class producer implements Runnable {
Test t;

producer(Test t) {
this.t = t;
}

public void run() {
// TODO Auto-generated method stub
Random r = new Random();
while (true) {
int temp = Math.abs(r.nextInt() % 100);
if (temp < 10) {
// break;
}
t.add(temp);
try {
Thread.sleep(Math.abs(r.nextInt()) % 100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

}

class consumer implements Runnable {

Test t;

consumer(Test t) {
this.t = t;
}

public void run() {
Random r = new Random();
while (true) {
int temp = t.rem();

try {
Thread.sleep(Math.abs(r.nextInt()) % 100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

}

请大家讨论讨论，谢了。