001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one or more
003 *  contributor license agreements.  See the NOTICE file distributed with
004 *  this work for additional information regarding copyright ownership.
005 *  The ASF licenses this file to You under the Apache License, Version 2.0
006 *  (the "License"); you may not use this file except in compliance with
007 *  the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 */
017package org.apache.commons.compress.archivers.sevenz;
018
019import java.util.Objects;
020
021/**
022 * Combines a SevenZMethod with configuration options for the method.
023 *
024 * <p>
025 * The exact type and interpretation of options depends on the method being configured. Currently supported are:
026 * </p>
027 *
028 * <table>
029 * <caption>Options</caption>
030 * <tr>
031 * <th>Method</th>
032 * <th>Option Type</th>
033 * <th>Description</th>
034 * </tr>
035 * <tr>
036 * <td>BZIP2</td>
037 * <td>Number</td>
038 * <td>Block Size - an number between 1 and 9</td>
039 * </tr>
040 * <tr>
041 * <td>DEFLATE</td>
042 * <td>Number</td>
043 * <td>Compression Level - an number between 1 and 9</td>
044 * </tr>
045 * <tr>
046 * <td>LZMA2</td>
047 * <td>Number</td>
048 * <td>Dictionary Size - a number between 4096 and 768 MiB (768 &lt;&lt; 20)</td>
049 * </tr>
050 * <tr>
051 * <td>LZMA2</td>
052 * <td>org.tukaani.xz.LZMA2Options</td>
053 * <td>Whole set of LZMA2 options.</td>
054 * </tr>
055 * <tr>
056 * <td>DELTA_FILTER</td>
057 * <td>Number</td>
058 * <td>Delta Distance - a number between 1 and 256</td>
059 * </tr>
060 * </table>
061 *
062 * @Immutable
063 * @since 1.8
064 */
065public class SevenZMethodConfiguration {
066    private final SevenZMethod method;
067    private final Object options;
068
069    /**
070     * Doesn't configure any additional options.
071     *
072     * @param method the method to use
073     */
074    public SevenZMethodConfiguration(final SevenZMethod method) {
075        this(method, null);
076    }
077
078    /**
079     * Specifies and method plus configuration options.
080     *
081     * @param method  the method to use
082     * @param options the options to use
083     * @throws IllegalArgumentException if the method doesn't understand the options specified.
084     */
085    public SevenZMethodConfiguration(final SevenZMethod method, final Object options) {
086        this.method = method;
087        this.options = options;
088        if (options != null && !Coders.findByMethod(method).isOptionInstance(options)) {
089            throw new IllegalArgumentException("The " + method + " method doesn't support options of type " + options.getClass());
090        }
091    }
092
093    @Override
094    public boolean equals(final Object obj) {
095        if (this == obj) {
096            return true;
097        }
098        if (obj == null || getClass() != obj.getClass()) {
099            return false;
100        }
101        final SevenZMethodConfiguration other = (SevenZMethodConfiguration) obj;
102        return Objects.equals(method, other.method) && Objects.equals(options, other.options);
103    }
104
105    /**
106     * The specified method.
107     *
108     * @return the method
109     */
110    public SevenZMethod getMethod() {
111        return method;
112    }
113
114    /**
115     * The specified options.
116     *
117     * @return the options
118     */
119    public Object getOptions() {
120        return options;
121    }
122
123    @Override
124    public int hashCode() {
125        return method == null ? 0 : method.hashCode();
126    }
127}