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 import java.util.Set;
35
36 import jdk.internal.loader.BootLoader;
37 import jdk.internal.loader.ClassLoaders;
38 import jdk.internal.misc.JavaLangReflectModuleAccess;
39 import jdk.internal.misc.SharedSecrets;
40
41 /**
42 * A helper class to allow JDK classes create dynamic modules and to update
43 * modules, exports and the readability graph. It is also invoked by the VM
44 * to add read edges when agents are instrumenting code that need to link
45 * to supporting classes.
46 *
47 * The parameters that are package names in this API are the fully-qualified
48 * names of the packages as defined in section 6.5.3 of <cite>The Java™
49 * Language Specification </cite>, for example, {@code "java.lang"}.
50 */
51
52 public class Modules {
53 private Modules() { }
54
55 private static final JavaLangReflectModuleAccess JLRMA
56 = SharedSecrets.getJavaLangReflectModuleAccess();
57
58 /**
59 * Creates a new Module. The module has the given ModuleDescriptor and
60 * is defined to the given class loader.
61 *
62 * The resulting Module is in a larval state in that it does not not read
63 * any other module and does not have any exports.
64 *
65 * The URI is for information purposes only.
66 */
67 public static Module defineModule(ClassLoader loader,
68 ModuleDescriptor descriptor,
69 URI uri)
70 {
71 return JLRMA.defineModule(loader, descriptor, uri);
72 }
73
74 /**
75 * Define a new module to the VM. The module has the given set of
76 * packages and is defined to the given class loader.
77 *
78 * The resulting Module is in a larval state in that it does not not read
79 * any other module and does not have any exports.
80 */
81 public static Module defineModule(ClassLoader loader,
82 String name,
83 Set<String> packages)
84 {
85 ModuleDescriptor descriptor = ModuleDescriptor.newModule(name)
86 .packages(packages)
87 .build();
88
89 return JLRMA.defineModule(loader, descriptor, null);
90 }
91
92 /**
93 * Adds a read-edge so that module {@code m1} reads module {@code m1}.
94 * Same as m1.addReads(m2) but without a caller check.
95 */
96 public static void addReads(Module m1, Module m2) {
97 JLRMA.addReads(m1, m2);
98 }
99
100 /**
101 * Update module {@code m} to read all unnamed modules.
102 */
103 public static void addReadsAllUnnamed(Module m) {
104 JLRMA.addReadsAllUnnamed(m);
105 }
106
107 /**
108 * Updates module m1 to export a package to module m2.
109 * Same as m1.addExports(pn, m2) but without a caller check.
110 */
111 public static void addExports(Module m1, String pn, Module m2) {
112 JLRMA.addExports(m1, pn, m2);
113 }
114
115 /**
116 * Updates module m1 to open a package to module m2.
117 * Same as m1.addOpens(pn, m2) but without a caller check.
118 */
119 public static void addOpens(Module m1, String pn, Module m2) {
120 JLRMA.addOpens(m1, pn, m2);
121 }
122
123 /**
124 * Updates a module m to export a package to all modules.
125 */
126 public static void addExportsToAll(Module m, String pn) {
127 JLRMA.addExportsToAll(m, pn);
128 }
129
130 /**
131 * Updates a module m to open a package to all modules.
132 */
133 public static void addOpensToAll(Module m, String pn) {
134 JLRMA.addOpensToAll(m, pn);
135 }
136
137 /**
138 * Updates module m to export a package to all unnamed modules.
139 */
140 public static void addExportsToAllUnnamed(Module m, String pn) {
141 JLRMA.addExportsToAllUnnamed(m, pn);
142 }
143
144 /**
145 * Updates module m to open a package to all unnamed modules.
146 */
147 public static void addOpensToAllUnnamed(Module m, String pn) {
148 JLRMA.addOpensToAllUnnamed(m, pn);
149 }
150
151 /**
152 * Updates module m to use a service
153 */
154 public static void addUses(Module m, Class<?> service) {
155 JLRMA.addUses(m, service);
156 }
157
158 /**
159 * Updates module m to provide a service
160 */
161 public static void addProvides(Module m, Class<?> service, Class<?> impl) {
162 Layer layer = m.getLayer();
163
164 if (layer == null || layer == Layer.boot()) {
165 // update ClassLoader catalog
166 PrivilegedAction<ClassLoader> pa = m::getClassLoader;
167 ClassLoader loader = AccessController.doPrivileged(pa);
168 ServicesCatalog catalog;
169 if (loader == null) {
170 catalog = BootLoader.getServicesCatalog();
171 } else {
172 catalog = ServicesCatalog.getServicesCatalog(loader);
173 }
174 catalog.addProvider(m, service, impl);
175 }
176
177 if (layer != null) {
178 // update Layer catalog
179 SharedSecrets.getJavaLangReflectModuleAccess()
180 .getServicesCatalog(layer)
181 .addProvider(m, service, impl);
182 }
183 }
184
185 /**
186 * Adds a package to a module's content.
187 *
188 * This method is a no-op if the module already contains the package or the
189 * module is an unnamed module.
190 */
191 public static void addPackage(Module m, String pn) {
192 JLRMA.addPackage(m, pn);
193 }
194
195 /**
196 * Called by the VM when code in the given Module has been transformed by
197 * an agent and so may have been instrumented to call into supporting
198 * classes on the boot class path or application class path.
199 */
200 public static void transformedByAgent(Module m) {
201 addReads(m, BootLoader.getUnnamedModule());
202 addReads(m, ClassLoaders.appClassLoader().getUnnamedModule());
203 }
204 }