public PriorityBlockingQueue<Path> getQueue(String walGroupId) {
    return queues.get(walGroupId);
  }
Return queue for the given walGroupId Please don't add or remove elements from the returned
queue. Use {@link #enqueueLog(Path, String)} and {@link #remove(String)} methods respectively.
@param walGroupId walGroupId
hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSourceLogQueue.java