1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 package org.apache.commons.compress.compressors.xz; 20 21 import java.io.IOException; 22 import java.io.OutputStream; 23 24 import org.apache.commons.compress.compressors.CompressorOutputStream; 25 import org.tukaani.xz.LZMA2Options; 26 import org.tukaani.xz.XZOutputStream; 27 28 /** 29 * XZ compressor. 30 * 31 * @since 1.4 32 */ 33 public class XZCompressorOutputStream extends CompressorOutputStream { 34 private final XZOutputStream out; 35 36 /** 37 * Creates a new XZ compressor using the default LZMA2 options. This is equivalent to {@code XZCompressorOutputStream(outputStream, 6)}. 38 * 39 * @param outputStream the stream to wrap 40 * @throws IOException on error 41 */ 42 public XZCompressorOutputStream(final OutputStream outputStream) throws IOException { 43 out = new XZOutputStream(outputStream, new LZMA2Options()); 44 } 45 46 /** 47 * Creates a new XZ compressor using the specified LZMA2 preset level. 48 * <p> 49 * The presets 0-3 are fast presets with medium compression. The presets 4-6 are fairly slow presets with high compression. The default preset is 6. 50 * <p> 51 * The presets 7-9 are like the preset 6 but use bigger dictionaries and have higher compressor and decompressor memory requirements. Unless the 52 * uncompressed size of the file exceeds 8 MiB, 16 MiB, or 32 MiB, it is waste of memory to use the presets 7, 8, or 9, respectively. 53 * 54 * @param outputStream the stream to wrap 55 * @param preset the preset 56 * @throws IOException on error 57 */ 58 public XZCompressorOutputStream(final OutputStream outputStream, final int preset) throws IOException { 59 out = new XZOutputStream(outputStream, new LZMA2Options(preset)); 60 } 61 62 @Override 63 public void close() throws IOException { 64 out.close(); 65 } 66 67 /** 68 * Finishes compression without closing the underlying stream. No more data can be written to this stream after finishing. 69 * 70 * @throws IOException on error 71 */ 72 public void finish() throws IOException { 73 out.finish(); 74 } 75 76 /** 77 * Flushes the encoder and calls {@code outputStream.flush()}. All buffered pending data will then be decompressible from the output stream. Calling this 78 * function very often may increase the compressed file size a lot. 79 */ 80 @Override 81 public void flush() throws IOException { 82 out.flush(); 83 } 84 85 @Override 86 public void write(final byte[] buf, final int off, final int len) throws IOException { 87 out.write(buf, off, len); 88 } 89 90 @Override 91 public void write(final int b) throws IOException { 92 out.write(b); 93 } 94 }