public void release() {
    underlying.unlock();
    isLocked = false;
  }
Releases the compile lock.

An underlying {@code Lock} implementation will usually impose restrictions on which
thread can release a lock (typically only the holder of the lock can release it)
and may throw an (unchecked) exception if the restriction is violated.
ql/src/java/org/apache/hadoop/hive/ql/lock/CompileLock.java