expose key and value iterators in ImmutableOpenMap

src/main/java/org/elasticsearch/cluster/node/DiscoveryNodes.java

@@ -34,7 +34,6 @@ import org.elasticsearch.common.regex.Regex;
 import org.elasticsearch.common.transport.TransportAddress;
 
 import java.io.IOException;
-import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -42,7 +41,7 @@ import java.util.Set;
 import static com.google.common.collect.Lists.newArrayList;
 
 /**
- * This class holds all {@link DiscoveryNode} in the cluster and provides convinience methods to
+ * This class holds all {@link DiscoveryNode} in the cluster and provides convenience methods to
  * access, modify merge / diff discovery nodes.
  */
 public class DiscoveryNodes implements Iterable<DiscoveryNode> {
@@ -50,13 +49,10 @@ public class DiscoveryNodes implements Iterable<DiscoveryNode> {
     public static final DiscoveryNodes EMPTY_NODES = builder().build();
 
     private final ImmutableOpenMap<String, DiscoveryNode> nodes;
-
     private final ImmutableOpenMap<String, DiscoveryNode> dataNodes;
-
     private final ImmutableOpenMap<String, DiscoveryNode> masterNodes;
 
     private final String masterNodeId;
-
     private final String localNodeId;
 
     private DiscoveryNodes(ImmutableOpenMap<String, DiscoveryNode> nodes, ImmutableOpenMap<String, DiscoveryNode> dataNodes, ImmutableOpenMap<String, DiscoveryNode> masterNodes, String masterNodeId, String localNodeId) {
@@ -69,18 +65,7 @@ public class DiscoveryNodes implements Iterable<DiscoveryNode> {
 
     @Override
     public UnmodifiableIterator<DiscoveryNode> iterator() {
-        final Iterator<ObjectCursor<DiscoveryNode>> cursor = nodes.values().iterator();
+        return nodes.valuesIt();
-        return new UnmodifiableIterator<DiscoveryNode>() {
-            @Override
-            public boolean hasNext() {
-                return cursor.hasNext();
-            }
-
-            @Override
-            public DiscoveryNode next() {
-                return cursor.next().value;
-            }
-        };
     }
 
     /**

src/main/java/org/elasticsearch/common/collect/ImmutableOpenMap.java

@@ -20,9 +20,11 @@
 package org.elasticsearch.common.collect;
 
 import com.carrotsearch.hppc.*;
+import com.carrotsearch.hppc.cursors.ObjectCursor;
 import com.carrotsearch.hppc.cursors.ObjectObjectCursor;
 import com.carrotsearch.hppc.predicates.ObjectPredicate;
 import com.carrotsearch.hppc.procedures.ObjectObjectProcedure;
+import com.google.common.collect.UnmodifiableIterator;
 
 import java.util.Iterator;
 import java.util.Map;
@@ -43,11 +45,11 @@ public final class ImmutableOpenMap<KType, VType> implements Iterable<ObjectObje
 
     /**
      * @return Returns the value associated with the given key or the default value
-     *         for the key type, if the key is not associated with any value.
+     * for the key type, if the key is not associated with any value.
-     *         <p/>
+     * <p/>
-     *         <b>Important note:</b> For primitive type values, the value returned for a non-existing
+     * <b>Important note:</b> For primitive type values, the value returned for a non-existing
-     *         key may not be the default value of the primitive type (it may be any value previously
+     * key may not be the default value of the primitive type (it may be any value previously
-     *         assigned to that slot).
+     * assigned to that slot).
      */
     public VType get(KType key) {
         return map.get(key);
@@ -106,6 +108,24 @@ public final class ImmutableOpenMap<KType, VType> implements Iterable<ObjectObje
         return map.keys();
     }
 
+    /**
+     * Returns a direct iterator over the keys.
+     */
+    public UnmodifiableIterator<KType> keysIt() {
+        final Iterator<ObjectCursor<KType>> iterator = map.keys().iterator();
+        return new UnmodifiableIterator<KType>() {
+            @Override
+            public boolean hasNext() {
+                return iterator.hasNext();
+            }
+
+            @Override
+            public KType next() {
+                return iterator.next().value;
+            }
+        };
+    }
+
     /**
      * @return Returns a container with all values stored in this map.
      */
@@ -113,6 +133,24 @@ public final class ImmutableOpenMap<KType, VType> implements Iterable<ObjectObje
         return map.values();
     }
 
+    /**
+     * Returns a direct iterator over the keys.
+     */
+    public UnmodifiableIterator<VType> valuesIt() {
+        final Iterator<ObjectCursor<VType>> iterator = map.values().iterator();
+        return new UnmodifiableIterator<VType>() {
+            @Override
+            public boolean hasNext() {
+                return iterator.hasNext();
+            }
+
+            @Override
+            public VType next() {
+                return iterator.next().value;
+            }
+        };
+    }
+
     @Override
     public String toString() {
         return map.toString();

src/main/java/org/elasticsearch/common/inject/internal/UnmodifiableIterator.java

@@ -1,36 +0,0 @@
-/*
- * Copyright (C) 2008 Google Inc.
- *
- * Licensed 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
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * 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.elasticsearch.common.inject.internal;
-
-import java.util.Iterator;
-
-/**
- * An iterator that does not support {@link #remove}.
- *
- * @author Jared Levy
- */
-public abstract class UnmodifiableIterator<E> implements Iterator<E> {
-
-    /**
-     * Guaranteed to throw an exception and leave the underlying data unmodified.
-     *
-     * @throws UnsupportedOperationException always
-     */
-    public final void remove() {
-        throw new UnsupportedOperationException();
-    }
-}