| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.runtime; |
| |
| import static jdk.nashorn.internal.codegen.Compiler.SCRIPTS_PACKAGE; |
| import static jdk.nashorn.internal.codegen.Compiler.binaryName; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.JS_OBJECT_DUAL_FIELD_PREFIX; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.JS_OBJECT_SINGLE_FIELD_PREFIX; |
| |
| import java.security.ProtectionDomain; |
| import jdk.nashorn.internal.codegen.ObjectClassGenerator; |
| |
| /** |
| * Responsible for on the fly construction of structure classes. |
| */ |
| final class StructureLoader extends NashornLoader { |
| private static final String SINGLE_FIELD_PREFIX = binaryName(SCRIPTS_PACKAGE) + '.' + JS_OBJECT_SINGLE_FIELD_PREFIX.symbolName(); |
| private static final String DUAL_FIELD_PREFIX = binaryName(SCRIPTS_PACKAGE) + '.' + JS_OBJECT_DUAL_FIELD_PREFIX.symbolName(); |
| |
| /** |
| * Constructor. |
| */ |
| StructureLoader(final ClassLoader parent) { |
| super(parent); |
| } |
| |
| /** |
| * Returns true if the class name represents a structure object with dual primitive/object fields. |
| * @param name a class name |
| * @return true if a dual field structure class |
| */ |
| private static boolean isDualFieldStructure(final String name) { |
| return name.startsWith(DUAL_FIELD_PREFIX); |
| } |
| |
| /** |
| * Returns true if the class name represents a structure object with single object-only fields. |
| * @param name a class name |
| * @return true if a single field structure class |
| */ |
| static boolean isSingleFieldStructure(final String name) { |
| return name.startsWith(SINGLE_FIELD_PREFIX); |
| } |
| |
| /** |
| * Returns true if the class name represents a Nashorn structure object. |
| * @param name a class name |
| * @return true if a structure class |
| */ |
| static boolean isStructureClass(final String name) { |
| return isDualFieldStructure(name) || isSingleFieldStructure(name); |
| } |
| |
| @Override |
| protected Class<?> findClass(final String name) throws ClassNotFoundException { |
| if (isDualFieldStructure(name)) { |
| return generateClass(name, name.substring(DUAL_FIELD_PREFIX.length()), true); |
| } else if (isSingleFieldStructure(name)) { |
| return generateClass(name, name.substring(SINGLE_FIELD_PREFIX.length()), false); |
| } |
| return super.findClass(name); |
| } |
| |
| /** |
| * Generate a layout class. |
| * @param name Name of class. |
| * @param descriptor Layout descriptor. |
| * @return Generated class. |
| */ |
| private Class<?> generateClass(final String name, final String descriptor, final boolean dualFields) { |
| final Context context = Context.getContextTrusted(); |
| |
| final byte[] code = new ObjectClassGenerator(context, dualFields).generate(descriptor); |
| return defineClass(name, code, 0, code.length, new ProtectionDomain(null, getPermissions(null))); |
| } |
| } |