1 /*
2 * Copyright (c) 2017, 2024, 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.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /* @test
25 * @enablePreview
26 * @modules java.base/java.lang:open
27 * @run testng/othervm test.DefineClassTest
28 * @summary Basic test for java.lang.invoke.MethodHandles.Lookup.defineClass
29 */
30
31 package test;
32
33 import java.lang.classfile.ClassFile;
34 import java.lang.constant.ClassDesc;
35 import java.lang.invoke.MethodHandles.Lookup;
36 import java.lang.reflect.AccessFlag;
37 import java.net.URL;
38 import java.net.URLClassLoader;
39 import java.nio.file.Files;
40 import java.nio.file.Path;
41 import java.nio.file.Paths;
42 import org.testng.annotations.Test;
43
44 import static java.lang.classfile.ClassFile.ACC_PUBLIC;
45 import static java.lang.classfile.ClassFile.ACC_STATIC;
46 import static java.lang.constant.ConstantDescs.CD_Object;
47 import static java.lang.constant.ConstantDescs.CLASS_INIT_NAME;
48 import static java.lang.constant.ConstantDescs.INIT_NAME;
49 import static java.lang.constant.ConstantDescs.MTD_void;
50 import static java.lang.invoke.MethodHandles.*;
51 import static java.lang.invoke.MethodHandles.Lookup.*;
52 import static org.testng.Assert.*;
53
54 public class DefineClassTest {
55 private static final String THIS_PACKAGE = DefineClassTest.class.getPackageName();
56 private static final ClassDesc CD_Runnable = Runnable.class.describeConstable().orElseThrow();
57 private static final ClassDesc CD_MissingSuperClass = ClassDesc.of("MissingSuperClass");
58
59 /**
60 * Test that a class has the same class loader, and is in the same package and
61 * protection domain, as a lookup class.
62 */
63 void testSameAbode(Class<?> clazz, Class<?> lc) {
64 assertTrue(clazz.getClassLoader() == lc.getClassLoader());
65 assertEquals(clazz.getPackageName(), lc.getPackageName());
66 assertTrue(clazz.getProtectionDomain() == lc.getProtectionDomain());
67 }
68
69 /**
70 * Tests that a class is discoverable by name using Class.forName and
71 * lookup.findClass
72 */
73 void testDiscoverable(Class<?> clazz, Lookup lookup) throws Exception {
74 String cn = clazz.getName();
75 ClassLoader loader = clazz.getClassLoader();
76 assertTrue(Class.forName(cn, false, loader) == clazz);
77 assertTrue(lookup.findClass(cn) == clazz);
78 }
79
80 /**
81 * Basic test of defineClass to define a class in the same package as test.
82 */
83 @Test
84 public void testDefineClass() throws Exception {
85 final String CLASS_NAME = THIS_PACKAGE + ".Foo";
86 Lookup lookup = lookup();
87 Class<?> clazz = lookup.defineClass(generateClass(CLASS_NAME));
88
89 // test name
90 assertEquals(clazz.getName(), CLASS_NAME);
91
92 // test loader/package/protection-domain
93 testSameAbode(clazz, lookup.lookupClass());
94
95 // test discoverable
96 testDiscoverable(clazz, lookup);
97
98 // attempt defineClass again
99 try {
100 lookup.defineClass(generateClass(CLASS_NAME));
101 assertTrue(false);
102 } catch (LinkageError expected) { }
103 }
104
105 /**
106 * Test public/package/protected/private access from class defined with defineClass.
107 */
108 @Test
109 public void testAccess() throws Exception {
110 final String THIS_CLASS = this.getClass().getName();
111 final String CLASS_NAME = THIS_PACKAGE + ".Runner";
112 Lookup lookup = lookup();
113
114 // public
115 byte[] classBytes = generateRunner(CLASS_NAME + nextNumber(), THIS_CLASS, "method1");
116 testInvoke(lookup.defineClass(classBytes));
117
118 // package
119 classBytes = generateRunner(CLASS_NAME + nextNumber(), THIS_CLASS, "method2");
120 testInvoke(lookup.defineClass(classBytes));
121
122 // protected (same package)
123 classBytes = generateRunner(CLASS_NAME + nextNumber(), THIS_CLASS, "method3");
124 testInvoke(lookup.defineClass(classBytes));
125
126 // private
127 classBytes = generateRunner(CLASS_NAME + nextNumber(), THIS_CLASS, "method4");
128 Class<?> clazz = lookup.defineClass(classBytes);
129 Runnable r = (Runnable) clazz.newInstance();
130 try {
131 r.run();
132 assertTrue(false);
133 } catch (IllegalAccessError expected) { }
134 }
135
136 public static void method1() { }
137 static void method2() { }
138 protected static void method3() { }
139 private static void method4() { }
140
141 void testInvoke(Class<?> clazz) throws Exception {
142 Object obj = clazz.newInstance();
143 ((Runnable) obj).run();
144 }
145
146 /**
147 * Test that defineClass does not run the class initializer
148 */
149 @Test
150 public void testInitializerNotRun() throws Exception {
151 final String THIS_CLASS = this.getClass().getName();
152 final String CLASS_NAME = THIS_PACKAGE + ".ClassWithClinit";
153
154 byte[] classBytes = generateClassWithInitializer(CLASS_NAME, THIS_CLASS, "fail");
155 Class<?> clazz = lookup().defineClass(classBytes);
156
157 // trigger initializer to run
158 try {
159 clazz.newInstance();
160 assertTrue(false);
161 } catch (ExceptionInInitializerError e) {
162 assertTrue(e.getCause() instanceof IllegalCallerException);
163 }
164 }
165
166 static void fail() { throw new IllegalCallerException(); }
167
168
169 /**
170 * Test defineClass to define classes in a package containing classes with
171 * different protection domains.
172 */
173 @Test
174 public void testTwoProtectionDomains() throws Exception {
175 Path here = Paths.get("");
176
177 // p.C1 in one exploded directory
178 Path dir1 = Files.createTempDirectory(here, "classes");
179 Path p = Files.createDirectory(dir1.resolve("p"));
180 Files.write(p.resolve("C1.class"), generateClass("p.C1"));
181 URL url1 = dir1.toUri().toURL();
182
183 // p.C2 in another exploded directory
184 Path dir2 = Files.createTempDirectory(here, "classes");
185 p = Files.createDirectory(dir2.resolve("p"));
186 Files.write(p.resolve("C2.class"), generateClass("p.C2"));
187 URL url2 = dir2.toUri().toURL();
188
189 // load p.C1 and p.C2
190 ClassLoader loader = new URLClassLoader(new URL[] { url1, url2 });
191 Class<?> target1 = Class.forName("p.C1", false, loader);
192 Class<?> target2 = Class.forName("p.C2", false, loader);
193 assertTrue(target1.getClassLoader() == loader);
194 assertTrue(target1.getClassLoader() == loader);
195 assertNotEquals(target1.getProtectionDomain(), target2.getProtectionDomain());
196
197 // protection domain 1
198 Lookup lookup1 = privateLookupIn(target1, lookup());
199
200 Class<?> clazz = lookup1.defineClass(generateClass("p.Foo"));
201 testSameAbode(clazz, lookup1.lookupClass());
202 testDiscoverable(clazz, lookup1);
203
204 // protection domain 2
205 Lookup lookup2 = privateLookupIn(target2, lookup());
206
207 clazz = lookup2.defineClass(generateClass("p.Bar"));
208 testSameAbode(clazz, lookup2.lookupClass());
209 testDiscoverable(clazz, lookup2);
210 }
211
212 /**
213 * Test defineClass defining a class to the boot loader
214 */
215 @Test
216 public void testBootLoader() throws Exception {
217 Lookup lookup = privateLookupIn(Thread.class, lookup());
218 assertTrue(lookup.getClass().getClassLoader() == null);
219
220 Class<?> clazz = lookup.defineClass(generateClass("java.lang.Foo"));
221 assertEquals(clazz.getName(), "java.lang.Foo");
222 testSameAbode(clazz, Thread.class);
223 testDiscoverable(clazz, lookup);
224 }
225
226 @Test(expectedExceptions = { IllegalArgumentException.class })
227 public void testWrongPackage() throws Exception {
228 lookup().defineClass(generateClass("other.C"));
229 }
230
231 @Test(expectedExceptions = { IllegalAccessException.class })
232 public void testNoPackageAccess() throws Exception {
233 Lookup lookup = lookup().dropLookupMode(PACKAGE);
234 lookup.defineClass(generateClass(THIS_PACKAGE + ".C"));
235 }
236
237 @Test(expectedExceptions = { ClassFormatError.class })
238 public void testTruncatedClassFile() throws Exception {
239 lookup().defineClass(new byte[0]);
240 }
241
242 @Test(expectedExceptions = { NullPointerException.class })
243 public void testNull() throws Exception {
244 lookup().defineClass(null);
245 }
246
247 @Test(expectedExceptions = { NoClassDefFoundError.class })
248 public void testLinking() throws Exception {
249 lookup().defineClass(generateNonLinkableClass(THIS_PACKAGE + ".NonLinkableClass"));
250 }
251
252 @Test(expectedExceptions = { IllegalArgumentException.class })
253 public void testModuleInfo() throws Exception {
254 lookup().defineClass(generateModuleInfo());
255 }
256
257 /**
258 * Generates a class file with the given class name
259 */
260 byte[] generateClass(String className) {
261 return ClassFile.of().build(ClassDesc.of(className), clb -> {
262 clb.withFlags(AccessFlag.PUBLIC, AccessFlag.IDENTITY);
263 clb.withSuperclass(CD_Object);
264 clb.withMethodBody(INIT_NAME, MTD_void, PUBLIC, cob -> {
265 cob.aload(0);
266 cob.invokespecial(CD_Object, INIT_NAME, MTD_void);
267 cob.return_();
268 });
269 });
270 }
271
272 /**
273 * Generate a class file with the given class name. The class implements Runnable
274 * with a run method to invokestatic the given targetClass/targetMethod.
275 */
276 byte[] generateRunner(String className,
277 String targetClass,
278 String targetMethod) throws Exception {
279
280 return ClassFile.of().build(ClassDesc.of(className), clb -> {
281 clb.withSuperclass(CD_Object);
282 clb.withInterfaceSymbols(CD_Runnable);
283 clb.withMethodBody(INIT_NAME, MTD_void, PUBLIC, cob -> {
284 cob.aload(0);
285 cob.invokespecial(CD_Object, INIT_NAME, MTD_void);
286 cob.return_();
287 });
288 clb.withMethodBody("run", MTD_void, PUBLIC, cob -> {
289 cob.invokestatic(ClassDesc.of(targetClass), targetMethod, MTD_void);
290 cob.return_();
291 });
292 });
293 }
294
295 /**
296 * Generate a class file with the given class name. The class will initializer
297 * to invokestatic the given targetClass/targetMethod.
298 */
299 byte[] generateClassWithInitializer(String className,
300 String targetClass,
301 String targetMethod) throws Exception {
302
303 return ClassFile.of().build(ClassDesc.of(className), clb -> {
304 clb.withFlags(AccessFlag.PUBLIC, AccessFlag.IDENTITY);
305 clb.withSuperclass(CD_Object);
306 clb.withMethodBody(INIT_NAME, MTD_void, ACC_PUBLIC, cob -> {
307 cob.aload(0);
308 cob.invokespecial(CD_Object, INIT_NAME, MTD_void);
309 cob.return_();
310 });
311 clb.withMethodBody(CLASS_INIT_NAME, MTD_void, ACC_STATIC, cob -> {
312 cob.invokestatic(ClassDesc.of(targetClass), targetMethod, MTD_void);
313 cob.return_();
314 });
315 });
316 }
317
318 /**
319 * Generates a non-linkable class file with the given class name
320 */
321 byte[] generateNonLinkableClass(String className) {
322 return ClassFile.of().build(ClassDesc.of(className), clb -> {
323 clb.withFlags(AccessFlag.PUBLIC, AccessFlag.IDENTITY);
324 clb.withSuperclass(CD_MissingSuperClass);
325 clb.withMethodBody(INIT_NAME, MTD_void, ACC_PUBLIC, cob -> {
326 cob.aload(0);
327 cob.invokespecial(CD_MissingSuperClass, INIT_NAME, MTD_void);
328 cob.return_();
329 });
330 });
331 }
332
333 /**
334 * Generates a class file with the given class name
335 */
336 byte[] generateModuleInfo() {
337 return ClassFile.of().build(ClassDesc.of("module-info"), cb -> cb.withFlags(AccessFlag.MODULE));
338 }
339
340 private int nextNumber() {
341 return ++nextNumber;
342 }
343
344 private int nextNumber;
345 }