Github user HeartSaVioR commented on a diff in the pull request:
https://github.com/apache/storm/pull/2433#discussion_r152900152
--- Diff:
storm-server/src/main/java/org/apache/storm/nimbus/LeaderListenerCallback.java
---
@@ -0,0 +1,213 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.storm.nimbus;
+
+import com.google.common.base.Joiner;
+import com.google.common.collect.Sets;
+import org.apache.commons.io.IOUtils;
+import org.apache.curator.framework.CuratorFramework;
+import org.apache.curator.framework.recipes.leader.LeaderLatch;
+import org.apache.storm.Config;
+import org.apache.storm.blobstore.BlobStore;
+import org.apache.storm.blobstore.InputStreamWithMeta;
+import org.apache.storm.cluster.ClusterUtils;
+import org.apache.storm.cluster.IStormClusterState;
+import org.apache.storm.daemon.nimbus.TopoCache;
+import org.apache.storm.generated.AuthorizationException;
+import org.apache.storm.generated.KeyNotFoundException;
+import org.apache.storm.generated.StormTopology;
+import org.apache.storm.security.auth.ReqContext;
+import org.apache.storm.utils.ConfigUtils;
+import org.apache.storm.utils.Utils;
+import org.apache.storm.zookeeper.ClientZookeeper;
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.data.ACL;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.security.auth.Subject;
+import java.io.IOException;
+import java.util.*;
--- End diff --
avoid wildcard import
---
