1 /* 2 * Copyright (c) 2018, 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.module; 27 28 import java.lang.module.ModuleFinder; 29 import java.util.Objects; 30 import jdk.internal.misc.VM; 31 32 /** 33 * Used by ModuleBootstrap to obtain the archived system modules and finder. 34 */ 35 final class ArchivedModuleGraph { 36 private static String archivedMainModule; 37 private static SystemModules archivedSystemModules; 38 private static ModuleFinder archivedModuleFinder; 39 40 private final SystemModules systemModules; 41 private final ModuleFinder finder; 42 43 private ArchivedModuleGraph(SystemModules modules, ModuleFinder finder) { 44 this.systemModules = modules; 45 this.finder = finder; 46 } 47 48 SystemModules systemModules() { 49 return systemModules; 50 } 51 52 ModuleFinder finder() { 53 return finder; 54 } 55 56 // A factory method that ModuleBootstrap can use to obtain the 57 // ArchivedModuleGraph. 58 static ArchivedModuleGraph get(String mainModule) { 59 if (Objects.equals(mainModule, archivedMainModule) 60 && archivedSystemModules != null 61 && archivedModuleFinder != null) { 62 return new ArchivedModuleGraph(archivedSystemModules, 63 archivedModuleFinder); 64 } else { 65 return null; 66 } 67 } 68 69 // Used at CDS dump time 70 static void archive(String mainModule, SystemModules systemModules, 71 ModuleFinder finder) { 72 if (archivedMainModule != null) 73 throw new UnsupportedOperationException(); 74 archivedMainModule = mainModule; 75 archivedSystemModules = systemModules; 76 archivedModuleFinder = finder; 77 } 78 79 static { 80 VM.initializeFromArchive(ArchivedModuleGraph.class); 81 } 82 }