Add more test cases on DistinctProjectionPrefixToken (#33684)

features/sharding/core/src/main/java/org/apache/shardingsphere/sharding/rewrite/token/pojo/DistinctProjectionPrefixToken.java

@@ -30,12 +30,12 @@ public DistinctProjectionPrefixToken(final int startIndex) {
     }
 
     @Override
-    public String toString() {
-        return "DISTINCT ";
+    public int getStopIndex() {
+        return getStartIndex();
     }
 
     @Override
-    public int getStopIndex() {
-        return getStartIndex();
+    public String toString() {
+        return "DISTINCT ";
     }
 }

features/sharding/core/src/test/java/org/apache/shardingsphere/sharding/rewrite/token/pojo/DistinctProjectionPrefixTokenTest.java

@@ -0,0 +1,36 @@
+/*
+ * 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.shardingsphere.sharding.rewrite.token.pojo;
+
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+class DistinctProjectionPrefixTokenTest {
+
+    @Test
+    void assertGetStopIndex() {
+        assertThat(new DistinctProjectionPrefixToken(10).getStopIndex(), is(10));
+    }
+
+    @Test
+    void assertToString() {
+        assertThat(new DistinctProjectionPrefixToken(0).toString(), is("DISTINCT "));
+    }
+}