| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.commons.compress.compressors.bzip2; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * Utility code for the BZip2 compression format. |
| * @ThreadSafe |
| * @since Commons Compress 1.1 |
| */ |
| public abstract class BZip2Utils { |
| |
| /** |
| * Map from common filename suffixes of bzip2ed files to the corresponding |
| * suffixes of uncompressed files. For example: from ".tbz2" to ".tar". |
| * <p> |
| * This map also contains bzip2-specific suffixes like ".bz2". These |
| * suffixes are mapped to the empty string, as they should simply be |
| * removed from the filename when the file is uncompressed. |
| */ |
| private static final Map uncompressSuffix = new HashMap(); |
| |
| static { |
| uncompressSuffix.put(".tbz2", ".tar"); |
| uncompressSuffix.put(".tbz", ".tar"); |
| uncompressSuffix.put(".bz2", ""); |
| uncompressSuffix.put(".bz", ""); |
| } |
| // N.B. if any shorter or longer keys are added, ensure the for loop limits are changed |
| |
| /** Private constructor to prevent instantiation of this utility class. */ |
| private BZip2Utils() { |
| } |
| |
| /** |
| * Detects common bzip2 suffixes in the given filename. |
| * |
| * @param filename name of a file |
| * @return <code>true</code> if the filename has a common bzip2 suffix, |
| * <code>false</code> otherwise |
| */ |
| public static boolean isCompressedFilename(String filename) { |
| String lower = filename.toLowerCase(); |
| int n = lower.length(); |
| // Shortest suffix is three letters (.bz), longest is five (.tbz2) |
| for (int i = 3; i <= 5 && i < n; i++) { |
| if (uncompressSuffix.containsKey(lower.substring(n - i))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Maps the given name of a bzip2-compressed file to the name that the |
| * file should have after uncompression. Commonly used file type specific |
| * suffixes like ".tbz" or ".tbz2" are automatically detected and |
| * correctly mapped. For example the name "package.tbz2" is mapped to |
| * "package.tar". And any filenames with the generic ".bz2" suffix |
| * (or any other generic bzip2 suffix) is mapped to a name without that |
| * suffix. If no bzip2 suffix is detected, then the filename is returned |
| * unmapped. |
| * |
| * @param filename name of a file |
| * @return name of the corresponding uncompressed file |
| */ |
| public static String getUncompressedFilename(String filename) { |
| String lower = filename.toLowerCase(); |
| int n = lower.length(); |
| // Shortest suffix is three letters (.bz), longest is five (.tbz2) |
| for (int i = 3; i <= 5 && i < n; i++) { |
| Object suffix = uncompressSuffix.get(lower.substring(n - i)); |
| if (suffix != null) { |
| return filename.substring(0, n - i) + suffix; |
| } |
| } |
| return filename; |
| } |
| |
| /** |
| * Maps the given filename to the name that the file should have after |
| * compression with bzip2. Currently this method simply appends the suffix |
| * ".bz2" to the filename based on the standard behaviour of the "bzip2" |
| * program, but a future version may implement a more complex mapping if |
| * a new widely used naming pattern emerges. |
| * |
| * @param filename name of a file |
| * @return name of the corresponding compressed file |
| */ |
| public static String getCompressedFilename(String filename) { |
| return filename + ".bz2"; |
| } |
| |
| } |