| /** |
| * 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; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| /** |
| * Abort data being written to a stream, so that close() does |
| * not write the data. It is implemented by output streams in |
| * some object stores, and passed through {@link FSDataOutputStream}. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Unstable |
| public interface Abortable { |
| |
| /** |
| * Abort the active operation without the output becoming visible. |
| * |
| * This is to provide ability to cancel the write on stream; once |
| * a stream is aborted, the write MUST NOT become visible. |
| * |
| * @throws UnsupportedOperationException if the operation is not supported. |
| * @return the result. |
| */ |
| AbortableResult abort(); |
| |
| /** |
| * Interface for the result of aborts; allows subclasses to extend |
| * (IOStatistics etc) or for future enhancements if ever needed. |
| */ |
| interface AbortableResult { |
| |
| /** |
| * Was the stream already closed/aborted? |
| * @return true if a close/abort operation had already |
| * taken place. |
| */ |
| boolean alreadyClosed(); |
| |
| /** |
| * Any exception caught during cleanup operations, |
| * exceptions whose raising/catching does not change |
| * the semantics of the abort. |
| * @return an exception or null. |
| */ |
| IOException anyCleanupException(); |
| } |
| } |