001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.commons.compress.compressors.xz;
020
021import java.io.IOException;
022import java.io.OutputStream;
023
024import org.apache.commons.compress.compressors.CompressorOutputStream;
025import org.apache.commons.io.build.AbstractStreamBuilder;
026import org.tukaani.xz.LZMA2Options;
027import org.tukaani.xz.XZOutputStream;
028
029// @formatter:off
030/**
031 * Compresses an output stream using the XZ and LZMA2 compression options.
032 * <p>
033 * For example:
034 * </p>
035 * <pre>{@code
036 * XZCompressorOutputStream s = XZCompressorOutputStream.builder()
037 *   .setPath(path)
038 *   .setLzma2Options(new LZMA2Options(...))
039 *   .get();
040 * }
041 * </pre>
042 *
043 * <h2>Calling flush</h2>
044 * <p>
045 * Calling {@link #flush()} flushes the encoder and calls {@code outputStream.flush()}. All buffered pending data will then be decompressible from the output
046 * stream. Calling this function very often may increase the compressed file size a lot.
047 * </p>
048 *
049 * @since 1.4
050 */
051// @formatter:on
052public class XZCompressorOutputStream extends CompressorOutputStream<XZOutputStream> {
053
054    // @formatter:off
055    /**
056     * Builds a new {@link XZCompressorOutputStream}.
057     *
058     * <p>
059     * For example:
060     * </p>
061     * <pre>{@code
062     * XZCompressorOutputStream s = XZCompressorOutputStream.builder()
063     *   .setPath(path)
064     *   .setLzma2Options(new LZMA2Options(...))
065     *   .get();
066     * }
067     * </pre>
068     *
069     * @see #get()
070     * @since 1.28.0
071     */
072    // @formatter:on
073    public static class Builder extends AbstractStreamBuilder<XZCompressorOutputStream, Builder> {
074
075        private LZMA2Options lzma2Options = new LZMA2Options();
076
077        /**
078         * Constructs a new builder of {@link XZCompressorOutputStream}.
079         */
080        public Builder() {
081            // empty
082        }
083
084        @Override
085        public XZCompressorOutputStream get() throws IOException {
086            return new XZCompressorOutputStream(this);
087        }
088
089        /**
090         * Sets LZMA options.
091         * <p>
092         * Passing {@code null} resets to the default value {@link LZMA2Options#LZMA2Options()}.
093         * </p>
094         *
095         * @param lzma2Options LZMA options.
096         * @return this instance.
097         */
098        public Builder setLzma2Options(final LZMA2Options lzma2Options) {
099            this.lzma2Options = lzma2Options != null ? lzma2Options : new LZMA2Options();
100            return this;
101        }
102
103    }
104
105    /**
106     * Constructs a new builder of {@link XZCompressorOutputStream}.
107     *
108     * @return a new builder of {@link XZCompressorOutputStream}.
109     * @since 1.28.0
110     */
111    public static Builder builder() {
112        return new Builder();
113    }
114
115    @SuppressWarnings("resource") // Caller closes
116    private XZCompressorOutputStream(final Builder builder) throws IOException {
117        super(new XZOutputStream(builder.getOutputStream(), builder.lzma2Options));
118        }
119
120    /**
121     * Creates a new XZ compressor using the default LZMA2 options. This is equivalent to {@code XZCompressorOutputStream(outputStream, 6)}.
122     *
123     * @param outputStream the stream to wrap
124     * @throws IOException on error
125     */
126    public XZCompressorOutputStream(final OutputStream outputStream) throws IOException {
127        this(builder().setOutputStream(outputStream));
128    }
129
130    /**
131     * Creates a new XZ compressor using the specified LZMA2 preset level.
132     * <p>
133     * 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.
134     * </p>
135     * <p>
136     * The presets 7-9 are like the preset 6 but use bigger dictionaries and have higher compressor and decompressor memory requirements. Unless the
137     * uncompressed size of the file exceeds 8&nbsp;MiB, 16&nbsp;MiB, or 32&nbsp;MiB, it is waste of memory to use the presets 7, 8, or 9, respectively.
138     * </p>
139     *
140     * @param outputStream the stream to wrap
141     * @param preset       the preset
142     * @throws IOException on error
143     * @deprecated Use {@link #builder()}.
144     */
145    @Deprecated
146    @SuppressWarnings("resource") // Caller closes
147    public XZCompressorOutputStream(final OutputStream outputStream, final int preset) throws IOException {
148        super(new XZOutputStream(outputStream, new LZMA2Options(preset)));
149    }
150
151    /**
152     * Finishes compression without closing the underlying stream. No more data can be written to this stream after finishing.
153     *
154     * @throws IOException on error
155     */
156    @Override
157    @SuppressWarnings("resource") // instance variable access
158    public void finish() throws IOException {
159        out().finish();
160    }
161
162    @Override
163    public void write(final byte[] buf, final int off, final int len) throws IOException {
164        out.write(buf, off, len);
165    }
166
167}