CompressorStream.java
上传用户:quxuerui
上传日期:2018-01-08
资源大小:41811k
文件大小:3k
- /*
- * 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.io.compress;
- import java.io.IOException;
- import java.io.OutputStream;
- import org.apache.hadoop.io.compress.CompressionOutputStream;
- import org.apache.hadoop.io.compress.Compressor;
- public class CompressorStream extends CompressionOutputStream {
- protected Compressor compressor;
- protected byte[] buffer;
- protected boolean closed = false;
-
- public CompressorStream(OutputStream out, Compressor compressor, int bufferSize) {
- super(out);
- if (out == null || compressor == null) {
- throw new NullPointerException();
- } else if (bufferSize <= 0) {
- throw new IllegalArgumentException("Illegal bufferSize");
- }
- this.compressor = compressor;
- buffer = new byte[bufferSize];
- }
- public CompressorStream(OutputStream out, Compressor compressor) {
- this(out, compressor, 512);
- }
-
- /**
- * Allow derived classes to directly set the underlying stream.
- *
- * @param out Underlying output stream.
- */
- protected CompressorStream(OutputStream out) {
- super(out);
- }
- public void write(byte[] b, int off, int len) throws IOException {
- // Sanity checks
- if (compressor.finished()) {
- throw new IOException("write beyond end of stream");
- }
- if ((off | len | (off + len) | (b.length - (off + len))) < 0) {
- throw new IndexOutOfBoundsException();
- } else if (len == 0) {
- return;
- }
- compressor.setInput(b, off, len);
- while (!compressor.needsInput()) {
- compress();
- }
- }
- protected void compress() throws IOException {
- int len = compressor.compress(buffer, 0, buffer.length);
- if (len > 0) {
- out.write(buffer, 0, len);
- }
- }
- public void finish() throws IOException {
- if (!compressor.finished()) {
- compressor.finish();
- while (!compressor.finished()) {
- compress();
- }
- }
- }
- public void resetState() throws IOException {
- compressor.reset();
- }
-
- public void close() throws IOException {
- if (!closed) {
- finish();
- out.close();
- closed = true;
- }
- }
- private byte[] oneByte = new byte[1];
- public void write(int b) throws IOException {
- oneByte[0] = (byte)(b & 0xff);
- write(oneByte, 0, oneByte.length);
- }
- }