ModuleGraphManipulator.java revision 1829:dbe6b239d681
1/* 2 * Copyright (c) 2016, 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 26package jdk.nashorn.internal.scripts; 27 28import java.lang.reflect.Module; 29import jdk.nashorn.api.scripting.JSObject; 30 31/** 32 * Nashorn's StructureLoader and ScriptLoader instances load 33 * this class in the respective dynamic modules created. This 34 * class is never loaded by Nashorn's own class loader. The 35 * .class bytes of this class are loaded as resource by the 36 * {@link jdk.nashorn.internal.runtime.NashornLoader} class. This class 37 * exists in this package because nashorn structures and scripts 38 * modules use this package name for the only exported package 39 * from those modules. 40 * 41 * Note that this class may be dynamically generated at runtime. 42 * But, this java source is used for ease of reading. 43 */ 44final class ModuleGraphManipulator { 45 private ModuleGraphManipulator() {} 46 47 private static final Module MY_MODULE; 48 private static final String MY_PKG_NAME; 49 50 static { 51 final Class<?> myClass = ModuleGraphManipulator.class; 52 MY_MODULE = myClass.getModule(); 53 final String myName = myClass.getName(); 54 MY_PKG_NAME = myName.substring(0, myName.lastIndexOf('.')); 55 56 // nashorn's module is the module of the class loader of current class 57 final Module nashornModule = myClass.getClassLoader().getClass().getModule(); 58 59 // Make sure this class was not loaded by Nashorn's own loader! 60 if (MY_MODULE == nashornModule) { 61 throw new IllegalStateException(myClass + " loaded by wrong loader!"); 62 } 63 64 // open package to nashorn module 65 MY_MODULE.addOpens(MY_PKG_NAME, nashornModule); 66 } 67 68 // The following method is reflectively invoked from Nashorn 69 // to add required module export edges. Because this package 70 // itself is qualified exported only to nashorn and this 71 // method is private, unsafe calls are not possible. 72 73 private static void addExport(final Module otherMod) { 74 MY_MODULE.addExports(MY_PKG_NAME, otherMod); 75 } 76} 77