init code

[vfc/nfvo/wfengine.git] / wso2 / wso2bpel-ext / wso2bpel-core / wso2bpel-mgr / src / main / java / org / openo / carbon / bpel / util / LRULinkedHashMap.java

diff --git a/wso2/wso2bpel-ext/wso2bpel-core/wso2bpel-mgr/src/main/java/org/openo/carbon/bpel/util/LRULinkedHashMap.java b/wso2/wso2bpel-ext/wso2bpel-core/wso2bpel-mgr/src/main/java/org/openo/carbon/bpel/util/LRULinkedHashMap.java
new file mode 100644 (file)
index 0000000..deb07c6
--- /dev/null
+++ b/wso2/wso2bpel-ext/wso2bpel-core/wso2bpel-mgr/src/main/java/org/openo/carbon/bpel/util/LRULinkedHashMap.java
@@ -0,0 +1,106 @@
+/**
+ * Copyright 2016 ZTE Corporation.
+ *
+ * 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.openo.carbon.bpel.util;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+/**
+ * 
+ * @author bsli
+ * 
+ * @param <K>
+ * @param <V>
+ */
+@SuppressWarnings("serial")
+public class LRULinkedHashMap<K, V> extends LinkedHashMap<K, V> {
+  private final int maxCapacity;
+
+  private static final float DEFAULT_LOAD_FACTOR = 0.75f;
+
+  private final Lock lock = new ReentrantLock();
+
+  public LRULinkedHashMap(int maxCapacity) {
+    super(maxCapacity, DEFAULT_LOAD_FACTOR, true);
+    this.maxCapacity = maxCapacity;
+  }
+
+  @Override
+  protected boolean removeEldestEntry(java.util.Map.Entry<K, V> eldest) {
+    return size() > maxCapacity;
+  }
+
+  @Override
+  public boolean containsKey(Object key) {
+    try {
+      lock.lock();
+      return super.containsKey(key);
+    } finally {
+      lock.unlock();
+    }
+  }
+
+  @Override
+  public V get(Object key) {
+    try {
+      lock.lock();
+      return super.get(key);
+    } finally {
+      lock.unlock();
+    }
+  }
+
+  @Override
+  public V put(K key, V value) {
+    try {
+      lock.lock();
+      return super.put(key, value);
+    } finally {
+      lock.unlock();
+    }
+  }
+
+  public int size() {
+    try {
+      lock.lock();
+      return super.size();
+    } finally {
+      lock.unlock();
+    }
+  }
+
+  public void clear() {
+    try {
+      lock.lock();
+      super.clear();
+    } finally {
+      lock.unlock();
+    }
+  }
+
+  public Collection<Map.Entry<K, V>> getAll() {
+    try {
+      lock.lock();
+      return new ArrayList<Map.Entry<K, V>>(super.entrySet());
+    } finally {
+      lock.unlock();
+    }
+  }
+}