当连接失败的时候，acquire会马上抛出异常的，你只要把异常catch住就好

public boolean acquire(long time,
                       TimeUnit unit)
                throws Exception
                
Acquire the mutex - blocks until it's available or the given time expires. Note: the same thread can call acquire re-entrantly. Each call to acquire that returns true must be balanced by a call to release()

Specified by:
acquire in interface InterProcessLock

Parameters:
time - time to wait
unit - time unit

Returns:
true if the mutex was acquired, false if not

Throws:
Exception - ZK errors, connection interruptions