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diff --git a/src/main/java/com/amazon/carbonado/util/AbstractPool.java b/src/main/java/com/amazon/carbonado/util/AbstractPool.java
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+/*
+ * Copyright 2006 Amazon Technologies, Inc. or its affiliates.
+ * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks
+ * of Amazon Technologies, Inc. or its affiliates.  All rights reserved.
+ *
+ * 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 com.amazon.carbonado.util;
+
+import java.util.Collection;
+
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.locks.Lock;
+
+/**
+ * A concurrent pool of strongly referenced values mapped by key. Values are
+ * lazily created and pooled.
+ *
+ * @author Brian S O'Neill
+ */
+public abstract class AbstractPool<K, V, E extends Exception> {
+    private final ConcurrentMap<K, V> mValues;
+    private final WeakReentrantLockPool<K> mLockPool;
+
+    protected AbstractPool() {
+        mValues = new ConcurrentHashMap<K, V>();
+        mLockPool = new WeakReentrantLockPool<K>();
+    }
+
+    /**
+     * Returns a value for the given key, which is lazily created and
+     * pooled. If multiple threads are requesting upon the same key
+     * concurrently, at most one thread attempts to lazily create the
+     * value. The others wait for it to become available.
+     */
+    public V get(K key) throws E {
+        // Quick check without locking.
+        V value = mValues.get(key);
+        if (value != null) {
+            return value;
+        }
+
+        // Check again with key lock held.
+        Lock lock = mLockPool.get(key);
+        lock.lock();
+        try {
+            value = mValues.get(key);
+            if (value == null) {
+                try {
+                    value = create(key);
+                    mValues.put(key, value);
+                } catch (Exception e) {
+                    // Workaround compiler bug.
+                    ThrowUnchecked.fire(e);
+                }
+            }
+        } finally {
+            lock.unlock();
+        }
+
+        return value;
+    }
+
+    /**
+     * Remove a value, returning the old value.
+     */
+    public V remove(Object key) {
+        return mValues.remove(key);
+    }
+
+    /**
+     * Returns the pool values, which may be concurrently modified.
+     */
+    public Collection<V> values() {
+        return mValues.values();
+    }
+
+    /**
+     * Return a new value instance.
+     */
+    protected abstract V create(K key) throws E;
+}