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 * http://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.bzip2; 020 021import java.util.LinkedHashMap; 022import java.util.Map; 023import org.apache.commons.compress.compressors.FileNameUtil; 024 025/** 026 * Utility code for the BZip2 compression format. 027 * @ThreadSafe 028 * @since 1.1 029 */ 030public abstract class BZip2Utils { 031 032 private static final FileNameUtil fileNameUtil; 033 034 static { 035 final Map<String, String> uncompressSuffix = 036 new LinkedHashMap<>(); 037 // backwards compatibilty: BZip2Utils never created the short 038 // tbz form, so .tar.bz2 has to be added explicitly 039 uncompressSuffix.put(".tar.bz2", ".tar"); 040 uncompressSuffix.put(".tbz2", ".tar"); 041 uncompressSuffix.put(".tbz", ".tar"); 042 uncompressSuffix.put(".bz2", ""); 043 uncompressSuffix.put(".bz", ""); 044 fileNameUtil = new FileNameUtil(uncompressSuffix, ".bz2"); 045 } 046 047 /** Private constructor to prevent instantiation of this utility class. */ 048 private BZip2Utils() { 049 } 050 051 /** 052 * Detects common bzip2 suffixes in the given filename. 053 * 054 * @param filename name of a file 055 * @return {@code true} if the filename has a common bzip2 suffix, 056 * {@code false} otherwise 057 */ 058 public static boolean isCompressedFilename(final String filename) { 059 return fileNameUtil.isCompressedFilename(filename); 060 } 061 062 /** 063 * Maps the given name of a bzip2-compressed file to the name that the 064 * file should have after uncompression. Commonly used file type specific 065 * suffixes like ".tbz" or ".tbz2" are automatically detected and 066 * correctly mapped. For example the name "package.tbz2" is mapped to 067 * "package.tar". And any filenames with the generic ".bz2" suffix 068 * (or any other generic bzip2 suffix) is mapped to a name without that 069 * suffix. If no bzip2 suffix is detected, then the filename is returned 070 * unmapped. 071 * 072 * @param filename name of a file 073 * @return name of the corresponding uncompressed file 074 */ 075 public static String getUncompressedFilename(final String filename) { 076 return fileNameUtil.getUncompressedFilename(filename); 077 } 078 079 /** 080 * Maps the given filename to the name that the file should have after 081 * compression with bzip2. Currently this method simply appends the suffix 082 * ".bz2" to the filename based on the standard behaviour of the "bzip2" 083 * program, but a future version may implement a more complex mapping if 084 * a new widely used naming pattern emerges. 085 * 086 * @param filename name of a file 087 * @return name of the corresponding compressed file 088 */ 089 public static String getCompressedFilename(final String filename) { 090 return fileNameUtil.getCompressedFilename(filename); 091 } 092 093}