Cleanup cache state from failed attempts of cluster discovering

Author: Spikhalskiy

src/main/java/redis/clients/jedis/BinaryJedisCluster.java

@@ -54,15 +54,7 @@ public BinaryJedisCluster(Set<HostAndPort> jedisClusterNode, int connectionTimeo
   @Override
   public void close() {
     if (connectionHandler != null) {
-      for (JedisPool pool : connectionHandler.getNodes().values()) {
-        try {
-          if (pool != null) {
-            pool.destroy();
-          }
-        } catch (Exception e) {
-          // pass
-        }
-      }
+      connectionHandler.close();
     }
   }
 

src/main/java/redis/clients/jedis/JedisClusterConnectionHandler.java

@@ -1,5 +1,6 @@
 package redis.clients.jedis;
 
+import java.io.Closeable;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -10,7 +11,7 @@
 
 import redis.clients.jedis.exceptions.JedisConnectionException;
 
-public abstract class JedisClusterConnectionHandler {
+public abstract class JedisClusterConnectionHandler implements Closeable {
   protected final JedisClusterInfoCache cache;
 
   public JedisClusterConnectionHandler(Set<HostAndPort> nodes,
@@ -73,6 +74,11 @@ public void renewSlotCache(Jedis jedis) {
     }
   }
 
+  @Override
+  public void close() {
+    cache.reset();
+  }
+
   protected List<JedisPool> getShuffledNodesPool() {
     List<JedisPool> pools = new ArrayList<JedisPool>();
     pools.addAll(cache.getNodes().values());

src/main/java/redis/clients/jedis/JedisClusterInfoCache.java

@@ -16,8 +16,8 @@
 import redis.clients.util.SafeEncoder;
 
 public class JedisClusterInfoCache {
-  private Map<String, JedisPool> nodes = new HashMap<String, JedisPool>();
-  private Map<Integer, JedisPool> slots = new HashMap<Integer, JedisPool>();
+  private final Map<String, JedisPool> nodes = new HashMap<String, JedisPool>();
+  private final Map<Integer, JedisPool> slots = new HashMap<Integer, JedisPool>();
 
   private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
   private final Lock r = rwl.readLock();
@@ -45,9 +45,7 @@ public void discoverClusterNodesAndSlots(Jedis jedis) {
     w.lock();
 
     try {
-      this.nodes.clear();
-      this.slots.clear();
-
+      reset();
       List<Object> slots = jedis.clusterSlots();
 
       for (Object slotInfoObj : slots) {
@@ -227,6 +225,28 @@ public Map<String, JedisPool> getNodes() {
     }
   }
 
+  /**
+   * Clear discovered nodes collections and gently release allocated resources
+   */
+  public void reset() {
+    w.lock();
+    try {
+      for (JedisPool pool : nodes.values()) {
+        try {
+          if (pool != null) {
+            pool.destroy();
+          }
+        } catch (Exception e) {
+          // pass
+        }
+      }
+      nodes.clear();
+      slots.clear();
+    } finally {
+      w.unlock();
+    }
+  }
+
   public static String getNodeKey(HostAndPort hnp) {
     return hnp.getHost() + ":" + hnp.getPort();
   }