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diff --git a/src/main/java/org/apache/commons/lang3/concurrent/AtomicInitializer.java b/src/main/java/org/apache/commons/lang3/concurrent/AtomicInitializer.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.commons.lang3.concurrent;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+/**
+ * A specialized implementation of the {@link ConcurrentInitializer} interface
+ * based on an {@link AtomicReference} variable.
+ *
+ * <p>
+ * This class maintains a member field of type {@link AtomicReference}. It
+ * implements the following algorithm to create and initialize an object in its
+ * {@link #get()} method:
+ * </p>
+ * <ul>
+ * <li>First it is checked whether the {@link AtomicReference} variable contains
+ * already a value. If this is the case, the value is directly returned.</li>
+ * <li>Otherwise the {@link #initialize()} method is called. This method must be
+ * defined in concrete subclasses to actually create the managed object.</li>
+ * <li>After the object was created by {@link #initialize()} it is checked
+ * whether the {@link AtomicReference} variable is still undefined. This has to
+ * be done because in the meantime another thread may have initialized the
+ * object. If the reference is still empty, the newly created object is stored
+ * in it and returned by this method.</li>
+ * <li>Otherwise the value stored in the {@link AtomicReference} is returned.</li>
+ * </ul>
+ * <p>
+ * Because atomic variables are used this class does not need any
+ * synchronization. So there is no danger of deadlock, and access to the managed
+ * object is efficient. However, if multiple threads access the {@code
+ * AtomicInitializer} object before it has been initialized almost at the same
+ * time, it can happen that {@link #initialize()} is called multiple times. The
+ * algorithm outlined above guarantees that {@link #get()} always returns the
+ * same object though.
+ * </p>
+ * <p>
+ * Compared with the {@link LazyInitializer} class, this class can be more
+ * efficient because it does not need synchronization. The drawback is that the
+ * {@link #initialize()} method can be called multiple times which may be
+ * problematic if the creation of the managed object is expensive. As a rule of
+ * thumb this initializer implementation is preferable if there are not too many
+ * threads involved and the probability that multiple threads access an
+ * uninitialized object is small. If there is high parallelism,
+ * {@link LazyInitializer} is more appropriate.
+ * </p>
+ *
+ * @since 3.0
+ * @param <T> the type of the object managed by this initializer class
+ */
+public abstract class AtomicInitializer<T> implements ConcurrentInitializer<T> {
+    /** Holds the reference to the managed object. */
+    private final AtomicReference<T> reference = new AtomicReference<>();
+
+    /**
+     * Returns the object managed by this initializer. The object is created if
+     * it is not available yet and stored internally. This method always returns
+     * the same object.
+     *
+     * @return the object created by this {@link AtomicInitializer}
+     * @throws ConcurrentException if an error occurred during initialization of
+     * the object
+     */
+    @Override
+    public T get() throws ConcurrentException {
+        T result = reference.get();
+
+        if (result == null) {
+            result = initialize();
+            if (!reference.compareAndSet(null, result)) {
+                // another thread has initialized the reference
+                result = reference.get();
+            }
+        }
+
+        return result;
+    }
+
+    /**
+     * Creates and initializes the object managed by this {@code
+     * AtomicInitializer}. This method is called by {@link #get()} when the
+     * managed object is not available yet. An implementation can focus on the
+     * creation of the object. No synchronization is needed, as this is already
+     * handled by {@code get()}. As stated by the class comment, it is possible
+     * that this method is called multiple times.
+     *
+     * @return the managed data object
+     * @throws ConcurrentException if an error occurs during object creation
+     */
+    protected abstract T initialize() throws ConcurrentException;
+}