1 files changed, 47 insertions, 0 deletions
diff --git a/framework/src/onos/utils/misc/src/main/java/org/onlab/util/NewConcurrentHashMap.java b/framework/src/onos/utils/misc/src/main/java/org/onlab/util/NewConcurrentHashMap.java
new file mode 100644
index 00000000..2d222eac
--- /dev/null
+++ b/framework/src/onos/utils/misc/src/main/java/org/onlab/util/NewConcurrentHashMap.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2014 Open Networking Laboratory
+ *
+ * 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.onlab.util;
+
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+import org.apache.commons.lang3.concurrent.ConcurrentInitializer;
+
+/**
+ * Creates an instance of new ConcurrentHashMap on each {@link #get()} call.
+ * <p>
+ * To be used with
+ * {@link org.apache.commons.lang3.concurrent.ConcurrentUtils#createIfAbsent}
+ * </p>
+ *
+ * @param <K> ConcurrentHashMap key type
+ * @param <V> ConcurrentHashMap value type
+ */
+public final class NewConcurrentHashMap<K, V>
+    implements  ConcurrentInitializer<ConcurrentMap<K, V>> {
+
+    public static final NewConcurrentHashMap<?, ?> INSTANCE = new NewConcurrentHashMap<>();
+
+    @SuppressWarnings("unchecked")
+    public static <K, V> NewConcurrentHashMap<K, V> ifNeeded() {
+        return (NewConcurrentHashMap<K, V>) INSTANCE;
+    }
+
+    @Override
+    public ConcurrentMap<K, V> get() {
+        return new ConcurrentHashMap<>();
+    }
+}