1 /*
2 * Copyright (c) 2018, 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 /*
25 * @test
26 * @library /test/lib
27 * @modules java.base/jdk.internal.org.objectweb.asm
28 * @build DefineClassWithClassData
29 * @run testng/othervm DefineClassWithClassData
30 */
31
32 import java.io.IOException;
33 import java.io.OutputStream;
34 import java.io.UncheckedIOException;
35 import java.lang.invoke.MethodHandles;
36 import java.lang.invoke.MethodHandles.Lookup;
37 import java.lang.reflect.InvocationTargetException;
38 import java.lang.reflect.Method;
39 import java.nio.file.Files;
40 import java.nio.file.Path;
41 import java.nio.file.Paths;
42 import java.util.List;
43 import java.util.stream.Stream;
44
45 import jdk.internal.org.objectweb.asm.*;
46 import org.testng.annotations.Test;
47
48 import static java.lang.invoke.MethodHandles.Lookup.ClassOption.*;
49 import static java.lang.invoke.MethodHandles.Lookup.PRIVATE;
50 import static jdk.internal.org.objectweb.asm.Opcodes.*;
51 import static org.testng.Assert.*;
52
53 public class DefineClassWithClassData {
54 private static final byte[] T_CLASS_BYTES = ClassByteBuilder.classBytes("T");
55 private static final byte[] T2_CLASS_BYTES = ClassByteBuilder.classBytes("T2");
56
57 private int privMethod() { return 1234; }
58
59 /*
60 * invoke int test(DefineClassWithClassData o) method defined in the injected class
61 */
62 private int testInjectedClass(Class<?> c) throws Throwable {
63 try {
64 Method m = c.getMethod("test", DefineClassWithClassData.class);
65 return (int) m.invoke(c.newInstance(), this);
66 } catch (InvocationTargetException e) {
67 throw e.getCause();
68 }
69 }
70
71 /*
72 * Returns the value of the static final "data" field in the injected class
73 */
74 private Object injectedData(Class<?> c) throws Throwable {
75 return c.getDeclaredField("data").get(null);
76 }
77
78 private static final List<String> classData = List.of("nestmate", "classdata");
79
80 @Test
81 public void defineNestMate() throws Throwable {
82 // define a nestmate
83 Lookup lookup = MethodHandles.lookup().defineHiddenClassWithClassData(T_CLASS_BYTES, classData, true, NESTMATE);
84 Class<?> c = lookup.lookupClass();
85 assertTrue(c.getNestHost() == DefineClassWithClassData.class);
86 assertEquals(classData, injectedData(c));
87
88 // invoke int test(DefineClassWithClassData o)
89 int x = testInjectedClass(c);
90 assertTrue(x == privMethod());
91
92 // dynamic nestmate is not listed in the return array of getNestMembers
93 assertTrue(Stream.of(c.getNestHost().getNestMembers()).noneMatch(k -> k == c));
94 assertTrue(c.isNestmateOf(DefineClassWithClassData.class));
95 }
96
97 @Test
98 public void defineHiddenClass() throws Throwable {
99 // define a hidden class
100 Lookup lookup = MethodHandles.lookup().defineHiddenClassWithClassData(T_CLASS_BYTES, classData, false, NESTMATE);
101 Class<?> c = lookup.lookupClass();
102 assertTrue(c.getNestHost() == DefineClassWithClassData.class);
103 assertTrue(c.isHiddenClass());
104 assertEquals(classData, injectedData(c));
105
106 // invoke int test(DefineClassWithClassData o)
107 int x = testInjectedClass(c);
108 assertTrue(x == privMethod());
109
110 // dynamic nestmate is not listed in the return array of getNestMembers
111 assertTrue(Stream.of(c.getNestHost().getNestMembers()).noneMatch(k -> k == c));
112 assertTrue(c.isNestmateOf(DefineClassWithClassData.class));
113 }
114
115 @Test
116 public void defineWeakClass() throws Throwable {
117 // define a weak class
118 Lookup lookup = MethodHandles.lookup().defineHiddenClassWithClassData(T_CLASS_BYTES, classData, true, WEAK);
119 Class<?> c = lookup.lookupClass();
120 assertTrue(c.getNestHost() == c);
121 assertTrue(c.isHiddenClass());
122 }
123
124 @Test(expectedExceptions = IllegalAccessException.class)
125 public void noPrivateLookupAccess() throws Throwable {
126 Lookup lookup = MethodHandles.lookup().dropLookupMode(Lookup.PRIVATE);
127 lookup.defineHiddenClassWithClassData(T2_CLASS_BYTES, classData, false, NESTMATE);
128 }
129
130 @Test
131 public void teleportToNestmate() throws Throwable {
132 Lookup lookup = MethodHandles.lookup()
133 .defineHiddenClassWithClassData(T_CLASS_BYTES, classData, false, NESTMATE);
134 Class<?> c = lookup.lookupClass();
135 assertTrue(c.getNestHost() == DefineClassWithClassData.class);
136 assertEquals(classData, injectedData(c));
137 assertTrue(c.isHiddenClass());
138
139 // Teleport to a nestmate
140 Lookup lookup2 = MethodHandles.lookup().in(DefineClassWithClassData.class);
141 assertTrue((lookup2.lookupModes() & PRIVATE) != 0);
142 Lookup lc = lookup2.defineHiddenClassWithClassData(T2_CLASS_BYTES, classData, false, NESTMATE);
143 assertTrue(lc.lookupClass().getNestHost() == DefineClassWithClassData.class);
144 assertTrue(lc.lookupClass().isHiddenClass());
145 }
146
147 static class ClassByteBuilder {
148 static final String OBJECT_CLS = "java/lang/Object";
149 static final String MHS_CLS = "java/lang/invoke/MethodHandles";
150 static final String LIST_SIG = "Ljava/util/List;";
151
152 static byte[] classBytes(String classname) {
153 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
154 MethodVisitor mv;
155 FieldVisitor fv;
156
157 String hostClassName = DefineClassWithClassData.class.getName();
158
159 cw.visit(V13, ACC_FINAL, classname, null, OBJECT_CLS, null);
160 {
161 fv = cw.visitField(ACC_STATIC | ACC_FINAL, "data", LIST_SIG, null, null);
162 fv.visitEnd();
163 }
164 {
165 mv = cw.visitMethod(ACC_STATIC, "<clinit>", "()V", null, null);
166 mv.visitCode();
167
168 Handle bsm = new Handle(H_INVOKESTATIC, MHS_CLS, "classData", "(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/Class;)Ljava/lang/Object;", false);
169 ConstantDynamic dynamic = new ConstantDynamic("classdata", LIST_SIG, bsm);
170 mv.visitLdcInsn(dynamic);
171 mv.visitFieldInsn(PUTSTATIC, classname, "data", LIST_SIG);
172 mv.visitInsn(RETURN);
173 mv.visitMaxs(0, 0);
174 mv.visitEnd();
175 }
176
177 {
178 mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
179 mv.visitCode();
180 mv.visitVarInsn(ALOAD, 0);
181 mv.visitMethodInsn(INVOKESPECIAL, OBJECT_CLS, "<init>", "()V", false);
182 mv.visitInsn(RETURN);
183 mv.visitMaxs(0, 0);
184 mv.visitEnd();
185 }
186 {
187 mv = cw.visitMethod(ACC_PUBLIC, "test", "(L" + hostClassName + ";)I", null, null);
188 mv.visitCode();
189 mv.visitVarInsn(ALOAD, 0);
190 mv.visitVarInsn(ALOAD, 1);
191 mv.visitMethodInsn(INVOKEVIRTUAL, hostClassName, "privMethod", "()I", false);
192 mv.visitInsn(IRETURN);
193 mv.visitMaxs(0, 0);
194 mv.visitEnd();
195 }
196
197 {
198 mv = cw.visitMethod(ACC_PUBLIC | ACC_STATIC, "printData", "()V", null, null);
199 mv.visitCode();
200 mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
201 mv.visitFieldInsn(GETSTATIC, classname, "data", LIST_SIG);
202 mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/Object;)V", false);
203 mv.visitInsn(RETURN);
204 mv.visitMaxs(0, 0);
205 mv.visitEnd();
206 }
207 cw.visitEnd();
208
209 byte[] bytes = cw.toByteArray();
210 Path p = Paths.get(classname + ".class");
211 try (OutputStream os = Files.newOutputStream(p)) {
212 os.write(bytes);
213 } catch (IOException e) {
214 throw new UncheckedIOException(e);
215 }
216 return bytes;
217 }
218 }
219 }
220
221