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.archivers.jar; 020 021import java.io.IOException; 022import java.io.InputStream; 023 024import org.apache.commons.compress.archivers.ArchiveEntry; 025import org.apache.commons.compress.archivers.zip.ZipArchiveEntry; 026import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream; 027 028/** 029 * Implements an input stream that can read entries from jar files. 030 * 031 * @NotThreadSafe 032 */ 033public class JarArchiveInputStream extends ZipArchiveInputStream { 034 035 /** 036 * Checks if the signature matches what is expected for a jar file 037 * (in this case it is the same as for a ZIP file). 038 * 039 * @param signature 040 * the bytes to check 041 * @param length 042 * the number of bytes to check 043 * @return true, if this stream is a jar archive stream, false otherwise 044 */ 045 public static boolean matches(final byte[] signature, final int length ) { 046 return ZipArchiveInputStream.matches(signature, length); 047 } 048 049 /** 050 * Creates an instance from the input stream using the default encoding. 051 * 052 * @param inputStream the input stream to wrap 053 */ 054 public JarArchiveInputStream( final InputStream inputStream ) { 055 super(inputStream); 056 } 057 058 /** 059 * Creates an instance from the input stream using the specified encoding. 060 * 061 * @param inputStream the input stream to wrap 062 * @param encoding the encoding to use 063 * @since 1.10 064 */ 065 public JarArchiveInputStream( final InputStream inputStream, final String encoding ) { 066 super(inputStream, encoding); 067 } 068 069 @Override 070 public ArchiveEntry getNextEntry() throws IOException { 071 return getNextJarEntry(); 072 } 073 074 public JarArchiveEntry getNextJarEntry() throws IOException { 075 final ZipArchiveEntry entry = getNextZipEntry(); 076 return entry == null ? null : new JarArchiveEntry(entry); 077 } 078}