1 /*
2 * Copyright (c) 2015, 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
26 package jdk.internal.module;
27
28 import java.lang.module.ModuleDescriptor;
29 import java.lang.reflect.Layer;
30 import java.lang.reflect.Module;
31 import java.net.URI;
32 import java.security.AccessController;
33 import java.security.PrivilegedAction;
34
35 import jdk.internal.loader.BootLoader;
36 import jdk.internal.loader.ClassLoaders;
37 import jdk.internal.misc.JavaLangReflectModuleAccess;
38 import jdk.internal.misc.SharedSecrets;
39
40 /**
41 * A helper class for creating and updating modules. This class is intended to
42 * support command-line options, tests, and the instrumentation API. It is also
43 * used by the VM to add read edges when agents are instrumenting code that
44 * need to link to supporting classes.
45 *
46 * The parameters that are package names in this API are the fully-qualified
47 * names of the packages as defined in section 6.5.3 of <cite>The Java™
48 * Language Specification </cite>, for example, {@code "java.lang"}.
49 */
50
51 public class Modules {
52 private Modules() { }
53
54 private static final JavaLangReflectModuleAccess JLRMA
55 = SharedSecrets.getJavaLangReflectModuleAccess();
56
57 /**
58 * Creates a new Module. The module has the given ModuleDescriptor and
59 * is defined to the given class loader.
60 *
61 * The resulting Module is in a larval state in that it does not not read
62 * any other module and does not have any exports.
63 *
64 * The URI is for information purposes only.
65 */
66 public static Module defineModule(ClassLoader loader,
67 ModuleDescriptor descriptor,
68 URI uri)
69 {
70 return JLRMA.defineModule(loader, descriptor, uri);
71 }
72
73 /**
74 * Updates m1 to read m2.
75 * Same as m1.addReads(m2) but without a caller check.
76 */
77 public static void addReads(Module m1, Module m2) {
78 JLRMA.addReads(m1, m2);
79 }
80
81 /**
82 * Update module m to read all unnamed modules.
83 */
84 public static void addReadsAllUnnamed(Module m) {
85 JLRMA.addReadsAllUnnamed(m);
86 }
87
88 /**
89 * Update module m to export a package to all modules.
90 *
91 * This method is for intended for use by tests only.
92 */
93 public static void addExports(Module m, String pn) {
94 JLRMA.addExports(m, pn);
95 }
96
97 /**
98 * Updates module m1 to export a package to module m2.
99 * Same as m1.addExports(pn, m2) but without a caller check
100 */
101 public static void addExports(Module m1, String pn, Module m2) {
102 JLRMA.addExports(m1, pn, m2);
103 }
104
105 /**
106 * Updates module m to export a package to all unnamed modules.
107 */
108 public static void addExportsToAllUnnamed(Module m, String pn) {
109 JLRMA.addExportsToAllUnnamed(m, pn);
110 }
111
112 /**
113 * Update module m to open a package to all modules.
114 *
115 * This method is for intended for use by tests only.
116 */
117 public static void addOpens(Module m, String pn) {
118 JLRMA.addOpens(m, pn);
119 }
120
121 /**
122 * Updates module m1 to open a package to module m2.
123 * Same as m1.addOpens(pn, m2) but without a caller check.
124 */
125 public static void addOpens(Module m1, String pn, Module m2) {
126 JLRMA.addOpens(m1, pn, m2);
127 }
128
129 /**
130 * Updates module m to open a package to all unnamed modules.
131 */
132 public static void addOpensToAllUnnamed(Module m, String pn) {
133 JLRMA.addOpensToAllUnnamed(m, pn);
134 }
135
136 /**
137 * Updates module m to use a service.
138 * Same as m2.addUses(service) but without a caller check.
139 */
140 public static void addUses(Module m, Class<?> service) {
141 JLRMA.addUses(m, service);
142 }
143
144 /**
145 * Updates module m to provide a service
146 */
147 public static void addProvides(Module m, Class<?> service, Class<?> impl) {
148 Layer layer = m.getLayer();
149
150 if (layer == null || layer == Layer.boot()) {
151 // update ClassLoader catalog
152 PrivilegedAction<ClassLoader> pa = m::getClassLoader;
153 ClassLoader loader = AccessController.doPrivileged(pa);
154 ServicesCatalog catalog;
155 if (loader == null) {
156 catalog = BootLoader.getServicesCatalog();
157 } else {
158 catalog = ServicesCatalog.getServicesCatalog(loader);
159 }
160 catalog.addProvider(m, service, impl);
161 }
162
163 if (layer != null) {
164 // update Layer catalog
165 SharedSecrets.getJavaLangReflectModuleAccess()
166 .getServicesCatalog(layer)
167 .addProvider(m, service, impl);
168 }
169 }
170
171 /**
172 * Called by the VM when code in the given Module has been transformed by
173 * an agent and so may have been instrumented to call into supporting
174 * classes on the boot class path or application class path.
175 */
176 public static void transformedByAgent(Module m) {
177 addReads(m, BootLoader.getUnnamedModule());
178 addReads(m, ClassLoaders.appClassLoader().getUnnamedModule());
179 }
180 }