ScriptLoader.java revision 1643:133ea8746b37 
1/*
2 * Copyright (c) 2010, 2013, 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.runtime;
27
28import java.lang.reflect.Module;
29import java.security.CodeSource;
30import java.util.Objects;
31
32/**
33 * Responsible for loading script generated classes.
34 *
35 */
36final class ScriptLoader extends NashornLoader {
37    private static final String NASHORN_PKG_PREFIX = "jdk.nashorn.internal.";
38
39    private volatile boolean structureAccessAdded;
40    private final Module scriptModule;
41    private final Context context;
42
43    /*package-private*/ Context getContext() {
44        return context;
45    }
46
47    /**
48     * Constructor.
49     */
50    ScriptLoader(final ClassLoader parent, final Context context) {
51        super(parent);
52        this.context = context;
53
54        // new scripts module, it's specific exports and read-edges
55        scriptModule = defineModule("jdk.scripting.nashorn.scripts", this);
56        addModuleExports(scriptModule, SCRIPTS_PKG, nashornModule);
57        addReadsModule(scriptModule, nashornModule);
58        addReadsModule(scriptModule, Object.class.getModule());
59
60        // specific exports from nashorn to new scripts module
61        nashornModule.addExports(OBJECTS_PKG, scriptModule);
62        nashornModule.addExports(RUNTIME_PKG, scriptModule);
63        nashornModule.addExports(RUNTIME_ARRAYS_PKG, scriptModule);
64        nashornModule.addExports(RUNTIME_LINKER_PKG, scriptModule);
65        nashornModule.addExports(SCRIPTS_PKG, scriptModule);
66
67        // nashorn needs to read scripts module methods,fields
68        nashornModule.addReads(scriptModule);
69    }
70
71    @Override
72    protected Class<?> loadClass(final String name, final boolean resolve) throws ClassNotFoundException {
73        checkPackageAccess(name);
74        if (name.startsWith(NASHORN_PKG_PREFIX)) {
75            final StructureLoader sharedCl = context.getSharedLoader();
76            final Class<?> cl = sharedCl.loadClass(name);
77            if (! structureAccessAdded) {
78                if (cl.getClassLoader() == sharedCl) {
79                    structureAccessAdded = true;
80                    final Module structModule = sharedCl.getModule();
81                    addModuleExports(structModule, SCRIPTS_PKG, scriptModule);
82                    addReadsModule(scriptModule, structModule);
83                }
84            }
85            return cl;
86        }
87        return super.loadClass(name, resolve);
88    }
89
90    // package-private and private stuff below this point
91
92    /**
93     * Install a class for use by the Nashorn runtime
94     *
95     * @param name Binary name of class.
96     * @param data Class data bytes.
97     * @param cs CodeSource code source of the class bytes.
98     *
99     * @return Installed class.
100     */
101    synchronized Class<?> installClass(final String name, final byte[] data, final CodeSource cs) {
102        return defineClass(name, data, 0, data.length, Objects.requireNonNull(cs));
103    }
104}
105