1 /* 2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nio.zipfs; 27 28 import java.io.IOException; 29 import java.io.InputStream; 30 import java.nio.file.Path; 31 import java.util.Arrays; 32 import java.util.HashMap; 33 import java.util.Map; 34 import java.util.TreeMap; 35 import java.util.function.Consumer; 36 import java.util.function.Function; 37 import java.util.jar.Attributes; 38 import java.util.jar.Manifest; 39 40 /** 41 * Adds aliasing to ZipFileSystem to support multi-release jar files. An alias map 42 * is created by {@link JarFileSystem#createVersionedLinks(int)}. The map is then 43 * consulted when an entry is looked up in {@link JarFileSystem#getEntry(byte[])} 44 * to determine if the entry has a corresponding versioned entry. If so, the 45 * versioned entry is returned. 46 * 47 * @author Steve Drach 48 */ 49 50 class JarFileSystem extends ZipFileSystem { 51 private Function<byte[],byte[]> lookup; 52 53 @Override 54 Entry getEntry(byte[] path) throws IOException { 55 // check for an alias to a versioned entry 56 byte[] versionedPath = lookup.apply(path); 57 return versionedPath == null ? super.getEntry(path) : super.getEntry(versionedPath); 58 } 59 60 JarFileSystem(ZipFileSystemProvider provider, Path zfpath, Map<String,?> env) 61 throws IOException { 62 super(provider, zfpath, env); 63 lookup = path -> path; // lookup needs to be set before isMultiReleaseJar is called 64 // because it eventually calls getEntry 65 if (isMultiReleaseJar()) { 66 int version; 67 Object o = env.get("multi-release"); 68 if (o instanceof String) { 69 String s = (String)o; 70 if (s.equals("runtime")) { 71 version = sun.misc.Version.jdkMajorVersion(); // fixme waiting for jdk.util.Version 72 } else { 73 version = Integer.parseInt(s); 74 } 75 } else if (o instanceof Integer) { 76 version = (Integer)o; 77 } else if (false /*o instanceof Version*/) { // fixme waiting for jdk.util.Version 78 // version = ((Version)o).major(); 79 } else { 80 throw new IllegalArgumentException("env parameter must be String, Integer, " 81 + "or Version"); 82 } 83 lookup = createVersionedLinks(version < 0 ? 0 : version); 84 setReadOnly(); 85 } 86 } 87 88 private boolean isMultiReleaseJar() { 89 try (InputStream is = newInputStream(getBytes("META-INF/MANIFEST.MF"))) { 90 return (new Manifest(is)).getMainAttributes() 91 .containsKey(new Attributes.Name("Multi-Release")); 92 // fixme change line above after JarFile integration to contain Attributes.Name.MULTI_RELEASE 93 } catch (IOException x) { 94 return false; 95 } 96 } 97 98 /** 99 * create a map of aliases for versioned entries, for example: 100 * version/PackagePrivate.class -> META-INF/versions/9/version/PackagePrivate.class 101 * version/PackagePrivate.java -> META-INF/versions/9/version/PackagePrivate.java 102 * version/Version.class -> META-INF/versions/10/version/Version.class 103 * version/Version.java -> META-INF/versions/10/version/Version.java 104 * 105 * then wrap the map in a function that getEntry can use to override root 106 * entry lookup for entries that have corresponding versioned entries 107 */ 108 private Function<byte[],byte[]> createVersionedLinks(int version) { 109 HashMap<IndexNode,byte[]> aliasMap = new HashMap<>(); 110 getVersionMap(version, getInode(getBytes("META-INF/versions"))).values() 111 .forEach(versionNode -> { // for each META-INF/versions/{n} directory 112 // put all the leaf inodes, i.e. entries, into the alias map 113 // possibly shadowing lower versioned entries 114 walk(versionNode, entryNode -> { 115 byte[] rootName = getRootName(versionNode, entryNode); 116 if (rootName != null) { 117 IndexNode rootNode = getInode(rootName); 118 if (rootNode == null) { // no matching root node, make a virtual one 119 rootNode = IndexNode.keyOf(rootName); 120 } 121 aliasMap.put(rootNode, entryNode.name); 122 } 123 }); 124 }); 125 return path -> aliasMap.get(IndexNode.keyOf(path)); 126 } 127 128 /** 129 * create a sorted version map of version -> inode, for inodes <= max version 130 * 9 -> META-INF/versions/9 131 * 10 -> META-INF/versions/10 132 */ 133 private TreeMap<Integer, IndexNode> getVersionMap(int version, IndexNode metaInfVersions) { 134 TreeMap<Integer,IndexNode> map = new TreeMap<>(); 135 IndexNode child = metaInfVersions.child; 136 while (child != null) { 137 Integer key = getVersion(child.name, metaInfVersions.name.length); 138 if (key != null && key <= version) { 139 map.put(key, child); 140 } 141 child = child.sibling; 142 } 143 return map; 144 } 145 146 /** 147 * extract the integer version number -- META-INF/versions/9 returns 9 148 */ 149 private Integer getVersion(byte[] name, int offset) { 150 try { 151 return Integer.parseInt(getString(Arrays.copyOfRange(name, offset, name.length-1))); 152 } catch (NumberFormatException x) { 153 // ignore this even though it might indicate issues with the JAR structure 154 return null; 155 } 156 } 157 158 /** 159 * walk the IndexNode tree processing all leaf nodes 160 */ 161 private void walk(IndexNode inode, Consumer<IndexNode> process) { 162 if (inode == null) return; 163 if (inode.isDir()) { 164 walk(inode.child, process); 165 } else { 166 process.accept(inode); 167 walk(inode.sibling, process); 168 } 169 } 170 171 /** 172 * extract the root name from a versioned entry name 173 * given inode for META-INF/versions/9/foo/bar.class 174 * and prefix META-INF/versions/9/ 175 * returns foo/bar.class 176 */ 177 private byte[] getRootName(IndexNode prefix, IndexNode inode) { 178 int offset = prefix.name.length; 179 byte[] fullName = inode.name; 180 return Arrays.copyOfRange(fullName, offset, fullName.length); 181 } 182 }