[ISSUE #8547] Add UnitTest of ControllableOffset (#8548)

client/src/test/java/org/apache/rocketmq/client/consumer/store/ControllableOffsetTest.java

@@ -0,0 +1,69 @@
+/*
+ * 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.rocketmq.client.consumer.store;
+
+
+import org.junit.Before;
+import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+
+public class ControllableOffsetTest {
+
+    private ControllableOffset controllableOffset;
+
+    @Before
+    public void setUp() {
+        controllableOffset = new ControllableOffset(0);
+    }
+
+    @Test
+    public void testUpdateAndFreeze_ShouldFreezeOffsetAtTargetValue() {
+        controllableOffset.updateAndFreeze(100);
+        assertEquals(100, controllableOffset.getOffset());
+        controllableOffset.update(200);
+        assertEquals(100, controllableOffset.getOffset());
+    }
+
+    @Test
+    public void testUpdate_ShouldUpdateOffsetWhenNotFrozen() {
+        controllableOffset.update(200);
+        assertEquals(200, controllableOffset.getOffset());
+    }
+
+    @Test
+    public void testUpdate_ShouldNotUpdateOffsetWhenFrozen() {
+        controllableOffset.updateAndFreeze(100);
+        controllableOffset.update(200);
+        assertEquals(100, controllableOffset.getOffset());
+    }
+
+    @Test
+    public void testUpdate_ShouldNotDecreaseOffsetWhenIncreaseOnly() {
+        controllableOffset.update(200);
+        controllableOffset.update(100, true);
+        assertEquals(200, controllableOffset.getOffset());
+    }
+
+    @Test
+    public void testUpdate_ShouldUpdateOffsetToGreaterValueWhenIncreaseOnly() {
+        controllableOffset.update(100);
+        controllableOffset.update(200, true);
+        assertEquals(200, controllableOffset.getOffset());
+    }
+
+}