| /** |
| * 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.*; |
| |
| /** Utility that wraps a {@link OutputStream} in a {@link DataOutputStream}, |
| * buffers output through a {@link BufferedOutputStream} and creates a checksum |
| * file. */ |
| public class FSDataOutputStream extends DataOutputStream implements Syncable { |
| private OutputStream wrappedStream; |
| |
| private static class PositionCache extends FilterOutputStream { |
| private FileSystem.Statistics statistics; |
| long position; |
| |
| public PositionCache(OutputStream out, |
| FileSystem.Statistics stats, |
| long pos) throws IOException { |
| super(out); |
| statistics = stats; |
| position = pos; |
| } |
| |
| public void write(int b) throws IOException { |
| out.write(b); |
| position++; |
| if (statistics != null) { |
| statistics.incrementBytesWritten(1); |
| } |
| } |
| |
| public void write(byte b[], int off, int len) throws IOException { |
| out.write(b, off, len); |
| position += len; // update position |
| if (statistics != null) { |
| statistics.incrementBytesWritten(len); |
| } |
| } |
| |
| public long getPos() throws IOException { |
| return position; // return cached position |
| } |
| |
| public void close() throws IOException { |
| out.close(); |
| } |
| } |
| |
| @Deprecated |
| public FSDataOutputStream(OutputStream out) throws IOException { |
| this(out, null); |
| } |
| |
| public FSDataOutputStream(OutputStream out, FileSystem.Statistics stats) |
| throws IOException { |
| this(out, stats, 0); |
| } |
| |
| public FSDataOutputStream(OutputStream out, FileSystem.Statistics stats, |
| long startPosition) throws IOException { |
| super(new PositionCache(out, stats, startPosition)); |
| wrappedStream = out; |
| } |
| |
| public long getPos() throws IOException { |
| return ((PositionCache)out).getPos(); |
| } |
| |
| public void close() throws IOException { |
| out.close(); // This invokes PositionCache.close() |
| } |
| |
| // Returns the underlying output stream. This is used by unit tests. |
| public OutputStream getWrappedStream() { |
| return wrappedStream; |
| } |
| |
| /** {@inheritDoc} */ |
| public void sync() throws IOException { |
| if (wrappedStream instanceof Syncable) { |
| ((Syncable)wrappedStream).sync(); |
| } |
| } |
| } |