add test: unit tests for MessageUtils utility class

common/src/test/java/org/apache/rocketmq/common/utils/MessageUtilsTest.java

@@ -0,0 +1,160 @@
+/*
+ * 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.common.utils;
+
+import java.util.Arrays;
+import java.util.Set;
+import org.apache.rocketmq.common.message.MessageExt;
+import org.apache.rocketmq.common.message.MessageConst;
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class MessageUtilsTest {
+
+    @Test
+    public void testGetShardingKeyIndex() {
+        String shardingKey = "test-key";
+        int indexSize = 10;
+        int index = MessageUtils.getShardingKeyIndex(shardingKey, indexSize);
+        assertThat(index).isBetween(0, indexSize - 1);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexWithEmptyKey() {
+        String shardingKey = "";
+        int indexSize = 5;
+        int index = MessageUtils.getShardingKeyIndex(shardingKey, indexSize);
+        assertThat(index).isBetween(0, indexSize - 1);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexWithChineseKey() {
+        String shardingKey = "测试分片键";
+        int indexSize = 100;
+        int index = MessageUtils.getShardingKeyIndex(shardingKey, indexSize);
+        assertThat(index).isBetween(0, indexSize - 1);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexConsistency() {
+        // Verify same input produces same output (deterministic)
+        String shardingKey = "test-key";
+        int indexSize = 10;
+        int index1 = MessageUtils.getShardingKeyIndex(shardingKey, indexSize);
+        int index2 = MessageUtils.getShardingKeyIndex(shardingKey, indexSize);
+        assertThat(index1).isEqualTo(index2);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexByMsg() {
+        MessageExt msg = new MessageExt();
+        msg.putUserProperty(MessageConst.PROPERTY_SHARDING_KEY, "sharding-123");
+        int index = MessageUtils.getShardingKeyIndexByMsg(msg, 10);
+        assertThat(index).isBetween(0, 9);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexByMsgWithNoShardingKey() {
+        // Verify fallback to empty string when no sharding key property is set
+        MessageExt msg = new MessageExt();
+        int index = MessageUtils.getShardingKeyIndexByMsg(msg, 10);
+        assertThat(index).isBetween(0, 9);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexes() {
+        MessageExt msg1 = new MessageExt();
+        msg1.putUserProperty(MessageConst.PROPERTY_SHARDING_KEY, "key-1");
+        MessageExt msg2 = new MessageExt();
+        msg2.putUserProperty(MessageConst.PROPERTY_SHARDING_KEY, "key-2");
+        MessageExt msg3 = new MessageExt();
+        msg3.putUserProperty(MessageConst.PROPERTY_SHARDING_KEY, "key-1");
+        Set<Integer> indexes = MessageUtils.getShardingKeyIndexes(Arrays.asList(msg1, msg2, msg3), 10);
+        assertThat(indexes).isNotEmpty();
+        assertThat(indexes).allMatch(i -> i >= 0 && i < 10);
+    }
+
+    @Test
+    public void testGetShardingKeyIndexesWithEmptyCollection() {
+        Set<Integer> indexes = MessageUtils.getShardingKeyIndexes(Arrays.asList(), 10);
+        assertThat(indexes).isEmpty();
+    }
+
+    @Test
+    public void testDeletePropertyFromSimpleString() {
+        String properties = "key1=value1;key2=value2;key3=value3";
+        String result = MessageUtils.deleteProperty(properties, "key2");
+        assertThat(result).isEqualTo("key1=value1;key3=value3");
+        assertThat(result).doesNotContain("key2");
+    }
+
+    @Test
+    public void testDeletePropertyFromNullString() {
+        String result = MessageUtils.deleteProperty(null, "key1");
+        assertThat(result).isNull();
+    }
+
+    @Test
+    public void testDeletePropertyKeyNotFound() {
+        String properties = "key1=value1;key2=value2";
+        String result = MessageUtils.deleteProperty(properties, "key3");
+        assertThat(result).isEqualTo("key1=value1;key2=value2");
+    }
+
+    @Test
+    public void testDeletePropertyDeleteFirstKey() {
+        String properties = "first=value1;second=value2";
+        String result = MessageUtils.deleteProperty(properties, "first");
+        assertThat(result).isEqualTo("second=value2");
+        assertThat(result).doesNotContain("first");
+    }
+
+    @Test
+    public void testDeletePropertyDeleteLastKey() {
+        String properties = "first=value1;last=value2";
+        String result = MessageUtils.deleteProperty(properties, "last");
+        assertThat(result).isEqualTo("first=value1");
+        assertThat(result).doesNotContain("last");
+    }
+
+    @Test
+    public void testDeletePropertyMultipleSameKeys() {
+        String properties = "key=value1;other=value2;key=value3";
+        String result = MessageUtils.deleteProperty(properties, "key");
+        assertThat(result).isEqualTo("other=value2");
+        assertThat(result).doesNotContain("key=");
+    }
+
+    @Test
+    public void testDeletePropertySubstringKeyMatch() {
+        // Deleting "key" should not affect "mykey"
+        String properties = "mykey=value1;key=value2;other=value3";
+        String result = MessageUtils.deleteProperty(properties, "key");
+        assertThat(result).contains("mykey=value1");
+        assertThat(result).doesNotContain("key=value2");
+    }
+
+    @Test
+    public void testDeletePropertyValueContainsKeyName() {
+        String properties = "topic=my-topic;msgId=abc123";
+        String result = MessageUtils.deleteProperty(properties, "msgId");
+        assertThat(result).isEqualTo("topic=my-topic");
+        assertThat(result).doesNotContain("msgId");
+    }
+}