1 /*
   2  * Copyright (c) 2014, 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.internal.jimage;
  27 
  28 import java.io.IOException;
  29 import java.nio.ByteBuffer;
  30 import java.nio.IntBuffer;
  31 import java.util.ArrayList;
  32 import java.util.HashMap;
  33 import java.util.List;
  34 import java.util.Map;
  35 
  36 // Utility to read module info from .jimage file.
  37 
  38 public final class PackageModuleMap {
  39     private PackageModuleMap() {}
  40 
  41     public static final String MODULES_ENTRY = "module/modules.offsets";
  42     public static final String PACKAGES_ENTRY = "packages.offsets";
  43 
  44     /*
  45      * Returns a package-to-module map.
  46      *
  47      * The package name is in binary name format.
  48      */
  49     static Map<String,String> readFrom(ImageReader reader) throws IOException {
  50         Map<String,String> result = new HashMap<>();
  51         List<String> moduleNames = reader.getNames(MODULES_ENTRY);
  52 
  53         for (String moduleName : moduleNames) {
  54             List<String> packageNames = reader.getNames(moduleName + "/" + PACKAGES_ENTRY);
  55 
  56             for (String packageName : packageNames) {
  57                 result.put(packageName, moduleName);
  58             }
  59         }
  60         return result;
  61     }
  62 }