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.Arrays; 020 021/** 022 * The (partially) supported compression/encryption methods used in 7z archives. 023 * 024 * <p>All methods with a _FILTER suffix are used as preprocessors with 025 * the goal of creating a better compression ratio with the compressor 026 * that comes next in the chain of methods. 7z will in general only 027 * allow them to be used together with a "real" compression method but 028 * Commons Compress doesn't enforce this.</p> 029 * 030 * <p>The BCJ_ filters work on executable files for the given platform 031 * and convert relative addresses to absolute addresses in CALL 032 * instructions. This means they are only useful when applied to 033 * executables of the chosen platform.</p> 034 */ 035public enum SevenZMethod { 036 /** no compression at all */ 037 COPY(new byte[] { (byte) 0x00 }), 038 /** LZMA - only supported when reading */ 039 LZMA(new byte[] { (byte) 0x03, (byte) 0x01, (byte) 0x01 }), 040 /** LZMA2 */ 041 LZMA2(new byte[] { (byte) 0x21 }), 042 /** Deflate */ 043 DEFLATE(new byte[] { (byte) 0x04, (byte) 0x01, (byte) 0x08 }), 044 /** 045 * Deflate64 046 * @since 1.16 047 */ 048 DEFLATE64(new byte[] { (byte) 0x04, (byte) 0x01, (byte) 0x09 }), 049 /** BZIP2 */ 050 BZIP2(new byte[] { (byte) 0x04, (byte) 0x02, (byte) 0x02 }), 051 /** 052 * AES encryption with a key length of 256 bit using SHA256 for 053 * hashes - only supported when reading 054 */ 055 AES256SHA256(new byte[] { (byte) 0x06, (byte) 0xf1, (byte) 0x07, (byte) 0x01 }), 056 /** 057 * BCJ x86 platform version 1. 058 * @since 1.8 059 */ 060 BCJ_X86_FILTER(new byte[] { 0x03, 0x03, 0x01, 0x03 }), 061 /** 062 * BCJ PowerPC platform. 063 * @since 1.8 064 */ 065 BCJ_PPC_FILTER(new byte[] { 0x03, 0x03, 0x02, 0x05 }), 066 /** 067 * BCJ I64 platform. 068 * @since 1.8 069 */ 070 BCJ_IA64_FILTER(new byte[] { 0x03, 0x03, 0x04, 0x01 }), 071 /** 072 * BCJ ARM platform. 073 * @since 1.8 074 */ 075 BCJ_ARM_FILTER(new byte[] { 0x03, 0x03, 0x05, 0x01 }), 076 /** 077 * BCJ ARM Thumb platform. 078 * @since 1.8 079 */ 080 BCJ_ARM_THUMB_FILTER(new byte[] { 0x03, 0x03, 0x07, 0x01 }), 081 /** 082 * BCJ Sparc platform. 083 * @since 1.8 084 */ 085 BCJ_SPARC_FILTER(new byte[] { 0x03, 0x03, 0x08, 0x05 }), 086 /** 087 * Delta filter. 088 * @since 1.8 089 */ 090 DELTA_FILTER(new byte[] { 0x03 }); 091 092 static SevenZMethod byId(final byte[] id) { 093 for (final SevenZMethod m : SevenZMethod.class.getEnumConstants()) { 094 if (Arrays.equals(m.id, id)) { 095 return m; 096 } 097 } 098 return null; 099 } 100 101 private final byte[] id; 102 103 SevenZMethod(final byte[] id) { 104 this.id = id; 105 } 106 107 byte[] getId() { 108 return Arrays.copyOf(id, id.length); 109 } 110}