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/*
* Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 8200261
* @summary Tests an anonymous class that implements interfaces with default methods.
* @library /testlibrary
* @modules java.base/jdk.internal.org.objectweb.asm
* java.management
* @compile -XDignore.symbol.file=true UnsafeDefMeths.java
* @run main UnsafeDefMeths
*/
import jdk.internal.org.objectweb.asm.ClassWriter;
import jdk.internal.org.objectweb.asm.MethodVisitor;
import jdk.internal.org.objectweb.asm.Type;
import sun.misc.Unsafe;
import java.lang.invoke.MethodType;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import static jdk.internal.org.objectweb.asm.Opcodes.ACC_PRIVATE;
import static jdk.internal.org.objectweb.asm.Opcodes.ACC_PUBLIC;
import static jdk.internal.org.objectweb.asm.Opcodes.ACC_SUPER;
import static jdk.internal.org.objectweb.asm.Opcodes.ALOAD;
import static jdk.internal.org.objectweb.asm.Opcodes.ARETURN;
import static jdk.internal.org.objectweb.asm.Opcodes.DUP;
import static jdk.internal.org.objectweb.asm.Opcodes.GETFIELD;
import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESPECIAL;
import static jdk.internal.org.objectweb.asm.Opcodes.PUTFIELD;
import static jdk.internal.org.objectweb.asm.Opcodes.RETURN;
import static jdk.internal.org.objectweb.asm.Opcodes.V1_8;
public class UnsafeDefMeths {
static final Unsafe UNSAFE;
static {
try {
Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");
unsafeField.setAccessible(true);
UNSAFE = (Unsafe) unsafeField.get(null);
}
catch (Exception e) {
throw new InternalError(e);
}
}
interface Resource {
Pointer ptr();
}
interface Struct extends Resource {
StructPointer ptr();
}
interface Pointer { }
interface StructPointer extends Pointer { }
interface I extends Struct {
void m();
}
static String IMPL_PREFIX = "$$impl";
static String PTR_FIELD_NAME = "ptr";
public static void main(String[] args) throws Throwable {
byte[] bytes = new UnsafeDefMeths().generate(I.class);
Class<?> cl = UNSAFE.defineAnonymousClass(I.class, bytes, new Object[0]);
I i = (I)cl.getConstructors()[0].newInstance(new Object[] { null }); //exception here!
}
// Generate a class similar to:
//
// public class UnsafeDefMeths$I$$impl implements UnsafeDefMeths$I, UnsafeDefMeths$Struct {
//
// public UnsafeDefMeths$StructPointer ptr;
//
// public UnsafeDefMeths$I$$impl(UnsafeDefMeths$StructPointer p) {
// ptr = p;
// }
//
// public UnsafeDefMeths$StructPointer ptr() {
// return ptr;
// }
// }
//
byte[] generate(Class<?> iface) {
ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS);
String ifaceTypeName = Type.getInternalName(iface);
String proxyClassName = ifaceTypeName + IMPL_PREFIX;
// class definition
cw.visit(V1_8, ACC_PUBLIC + ACC_SUPER, proxyClassName,
desc(Object.class) + desc(ifaceTypeName) + desc(Struct.class),
name(Object.class),
new String[] { ifaceTypeName, name(Struct.class) });
cw.visitField(ACC_PUBLIC, PTR_FIELD_NAME, desc(StructPointer.class), desc(StructPointer.class), null);
cw.visitEnd();
// constructor
MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>",
meth(desc(void.class), desc(StructPointer.class)),
meth(desc(void.class), desc(StructPointer.class)), null);
mv.visitCode();
mv.visitVarInsn(ALOAD, 0);
mv.visitInsn(DUP);
mv.visitMethodInsn(INVOKESPECIAL, name(Object.class), "<init>", meth(desc(void.class)), false);
mv.visitVarInsn(ALOAD, 1);
// Execution of this PUTFIELD instruction causes the bug's ClassNotFoundException.
mv.visitFieldInsn(PUTFIELD, proxyClassName, PTR_FIELD_NAME, desc(StructPointer.class));
mv.visitInsn(RETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
// ptr() impl
mv = cw.visitMethod(ACC_PUBLIC, PTR_FIELD_NAME, meth(desc(StructPointer.class)),
meth(desc(StructPointer.class)), null);
mv.visitCode();
mv.visitVarInsn(ALOAD, 0);
mv.visitFieldInsn(GETFIELD, proxyClassName, PTR_FIELD_NAME, desc(StructPointer.class));
mv.visitInsn(ARETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
return cw.toByteArray();
}
String name(Class<?> clazz) {
if (clazz.isPrimitive()) {
throw new IllegalStateException();
} else if (clazz.isArray()) {
return desc(clazz);
} else {
return clazz.getName().replaceAll("\\.", "/");
}
}
String desc(Class<?> clazz) {
String mdesc = MethodType.methodType(clazz).toMethodDescriptorString();
return mdesc.substring(mdesc.indexOf(')') + 1);
}
String desc(String clazzName) {
return "L" + clazzName + ";";
}
String gen(String clazz, String... typeargs) {
return clazz.substring(0, clazz.length() - 1) + Stream.of(typeargs).collect(Collectors.joining("", "<", ">")) + ";";
}
String meth(String restype, String... argtypes) {
return Stream.of(argtypes).collect(Collectors.joining("", "(", ")")) + restype;
}
String meth(Method m) {
return MethodType.methodType(m.getReturnType(), m.getParameterTypes()).toMethodDescriptorString();
}
}
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