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diff --git a/src/test/java/org/apache/commons/lang3/concurrent/AtomicSafeInitializerTest.java b/src/test/java/org/apache/commons/lang3/concurrent/AtomicSafeInitializerTest.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 static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test class for {@code AtomicSafeInitializer} which also serves as a simple example.
+ */
+public class AtomicSafeInitializerTest extends AbstractConcurrentInitializerTest {
+
+    /** The instance to be tested. */
+    private AtomicSafeInitializerTestImpl initializer;
+
+    @BeforeEach
+    public void setUp() {
+        initializer = new AtomicSafeInitializerTestImpl();
+    }
+
+    /**
+     * Returns the initializer to be tested.
+     *
+     * @return the {@code AtomicSafeInitializer} under test
+     */
+    @Override
+    protected ConcurrentInitializer<Object> createInitializer() {
+        return initializer;
+    }
+
+    /**
+     * Tests that initialize() is called only once.
+     *
+     * @throws org.apache.commons.lang3.concurrent.ConcurrentException because {@link #testGetConcurrent()} may throw it
+     * @throws InterruptedException because {@link #testGetConcurrent()} may throw it
+     */
+    @Test
+    public void testNumberOfInitializeInvocations() throws ConcurrentException, InterruptedException {
+        testGetConcurrent();
+        assertEquals(1, initializer.initCounter.get(), "Wrong number of invocations");
+    }
+
+    /**
+     * A concrete test implementation of {@code AtomicSafeInitializer} which also serves as a simple example.
+     * <p>
+     * This implementation also counts the number of invocations of the initialize() method.
+     * </p>
+     */
+    private static class AtomicSafeInitializerTestImpl extends AtomicSafeInitializer<Object> {
+        /** A counter for initialize() invocations. */
+        final AtomicInteger initCounter = new AtomicInteger();
+
+        @Override
+        protected Object initialize() {
+            initCounter.incrementAndGet();
+            return new Object();
+        }
+    }
+}