added asf and javadocs on RenameAtomicityTestUtils

hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/RenameAtomicityTestUtils.java

@@ -1,3 +1,21 @@
+/**
+ * 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.hadoop.fs.azurebfs.services;
 
 import org.mockito.Mockito;
@@ -9,6 +27,13 @@
 
 public class RenameAtomicityTestUtils {
 
+  /**
+   * Creates a spied object of {@link BlobRenameHandler} and {@link RenameAtomicity}
+   * and adds mocked behavior to {@link RenameAtomicity#createRenamePendingJson(Path, byte[])}.
+   *
+   * @param client client that would supply BlobRenameHandler and RenameAtomicity.
+   * @param answer mocked behavior for {@link RenameAtomicity#createRenamePendingJson(Path, byte[])}.
+   */
   public static void addCreatePathMock(AbfsBlobClient client, Answer answer) {
     Mockito.doAnswer(clientHandlerAns -> {
           BlobRenameHandler renameHandler = Mockito.spy(
@@ -32,6 +57,15 @@ public static void addCreatePathMock(AbfsBlobClient client, Answer answer) {
                 TracingContext.class));
   }
 
+
+  /**
+   * Adds mocked behavior to {@link RenameAtomicity#readRenamePendingJson(Path, int)}.
+   *
+   * @param redoRenameAtomicity {@link RenameAtomicity} to be spied.
+   * @param answer mocked behavior for {@link RenameAtomicity#readRenamePendingJson(Path, int)}.
+   *
+   * @throws AzureBlobFileSystemException server error or error from mocked behavior.
+   */
   public static void addReadPathMock(RenameAtomicity redoRenameAtomicity,
       Answer answer)
       throws AzureBlobFileSystemException {