Examples with ClassWriter org.apache.xbean.asm6.ClassWriter used on opensource projects

Example 6 with ClassWriter

use of org.apache.xbean.asm6.ClassWriter in project component-runtime by Talend.

the class ProxyGenerator method createConstructor.

private String createConstructor(final ClassWriter cw, final Class<?> classToProxy, final String classFileName, final String proxyClassFileName, final Constructor<?> constructor, final boolean withInterceptors) {
    try {
        Constructor superDefaultCt;
        String parentClassFileName;
        String[] exceptions = null;
        if (classToProxy.isInterface()) {
            parentClassFileName = Type.getInternalName(Object.class);
            superDefaultCt = Object.class.getConstructor();
        } else {
            parentClassFileName = classFileName;
            if (constructor == null) {
                superDefaultCt = classToProxy.getConstructor();
            } else {
                superDefaultCt = constructor;
                Class<?>[] exceptionTypes = constructor.getExceptionTypes();
                exceptions = exceptionTypes.length == 0 ? null : new String[exceptionTypes.length];
                for (int i = 0; i < exceptionTypes.length; i++) {
                    exceptions[i] = Type.getInternalName(exceptionTypes[i]);
                }
            }
        }
        final String descriptor = Type.getConstructorDescriptor(superDefaultCt);
        final MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>", descriptor, null, exceptions);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        if (constructor != null) {
            for (int i = 1; i <= constructor.getParameterTypes().length; i++) {
                mv.visitVarInsn(ALOAD, i);
            }
        }
        mv.visitMethodInsn(INVOKESPECIAL, parentClassFileName, "<init>", descriptor, false);
        if (withInterceptors) {
            mv.visitVarInsn(ALOAD, 0);
            mv.visitInsn(ACONST_NULL);
            mv.visitFieldInsn(PUTFIELD, proxyClassFileName, FIELD_INTERCEPTOR_HANDLER, Type.getDescriptor(InterceptorHandler.class));
        }
        mv.visitInsn(RETURN);
        mv.visitMaxs(-1, -1);
        mv.visitEnd();
        return parentClassFileName;
    } catch (final NoSuchMethodException e) {
        throw new IllegalStateException(e);
    }
}

Example 7 with ClassWriter

use of org.apache.xbean.asm6.ClassWriter in project component-runtime by Talend.

the class ProxyGenerator method generateProxy.

public Class<?> generateProxy(final ClassLoader loader, final Class<?> classToProxy, final String plugin, final String key) {
    final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
    final String proxyClassName = fixPreservedPackages((classToProxy.getSigners() != null ? getSignedClassProxyName(classToProxy) : classToProxy.getName()) + "$$TalendServiceProxy");
    final String classFileName = proxyClassName.replace('.', '/');
    final String[] interfaceNames = { Type.getInternalName(Serializable.class) };
    final String superClassName = Type.getInternalName(classToProxy);
    cw.visit(findJavaVersion(classToProxy), ACC_PUBLIC + ACC_SUPER + ACC_SYNTHETIC, classFileName, null, superClassName, interfaceNames);
    cw.visitSource(classFileName + ".java", null);
    if (!Serializable.class.isAssignableFrom(classToProxy)) {
        try {
            classToProxy.getMethod("writeReplace");
        } catch (final NoSuchMethodException e) {
            createSerialisation(cw, plugin, key);
        }
    }
    final boolean hasInterceptors = hasInterceptors(classToProxy);
    if (hasInterceptors) {
        cw.visitField(ACC_PRIVATE, FIELD_INTERCEPTOR_HANDLER, Type.getDescriptor(InterceptorHandler.class), null, null).visitEnd();
        cw.visitField(ACC_PRIVATE | ACC_STATIC, FIELD_INTERCEPTED_METHODS, Type.getDescriptor(Method[].class), null, null).visitEnd();
    }
    createConstructor(cw, classToProxy, superClassName, classFileName, Stream.of(classToProxy.getDeclaredConstructors()).filter(c -> {
        final int modifiers = c.getModifiers();
        return Modifier.isPublic(modifiers) || Modifier.isProtected(modifiers);
    }).sorted((o1, o2) -> {
        // prefer public constructor and then the smallest parameter count
        final int mod1 = o1.getModifiers();
        final int mod2 = o2.getModifiers();
        if (Modifier.isProtected(mod1) && !Modifier.isPublic(mod2)) {
            return 1;
        }
        if (Modifier.isProtected(mod2) && !Modifier.isPublic(mod1)) {
            return -1;
        }
        return o1.getParameterCount() - o2.getParameterCount();
    }).findFirst().orElseThrow(() -> new IllegalArgumentException(classToProxy + " has no default constructor, put at least a protected one")), hasInterceptors);
    final Method[] interceptedMethods;
    if (hasInterceptors) {
        final Collection<Annotation> globalInterceptors = Stream.of(classToProxy.getAnnotations()).filter(this::isInterceptor).collect(toList());
        final AtomicInteger methodIndex = new AtomicInteger();
        interceptedMethods = Stream.of(classToProxy.getMethods()).filter(m -> !"<init>".equals(m.getName()) && (!globalInterceptors.isEmpty() || Stream.of(m.getAnnotations()).anyMatch(this::isInterceptor))).peek(method -> delegateMethod(cw, method, classFileName, methodIndex.getAndIncrement())).toArray(Method[]::new);
    } else {
        interceptedMethods = null;
    }
    final Class<Object> objectClass = Unsafes.defineAndLoadClass(loader, proxyClassName, cw.toByteArray());
    if (hasInterceptors) {
        try {
            final Field interceptedMethodsField = objectClass.getDeclaredField(FIELD_INTERCEPTED_METHODS);
            interceptedMethodsField.setAccessible(true);
            interceptedMethodsField.set(null, interceptedMethods);
        } catch (final Exception e) {
            throw new IllegalStateException(e);
        }
    }
    return objectClass;
}

Example 8 with ClassWriter

use of org.apache.xbean.asm6.ClassWriter in project component-runtime by Talend.

the class ProxyGenerator method delegateMethod.

private void delegateMethod(final ClassWriter cw, final Method method, final String proxyClassFileName, final int methodIndex) {
    final Class<?> returnType = method.getReturnType();
    final Class<?>[] parameterTypes = method.getParameterTypes();
    final Class<?>[] exceptionTypes = method.getExceptionTypes();
    final int modifiers = method.getModifiers();
    if (Modifier.isFinal(modifiers) || Modifier.isStatic(modifiers)) {
        throw new IllegalStateException("It's not possible to proxy a final or static method: " + method.getDeclaringClass().getName() + " " + method.getName());
    }
    // push the method definition
    int modifier = modifiers & (ACC_PUBLIC | ACC_PROTECTED | ACC_VARARGS);
    MethodVisitor mv = cw.visitMethod(modifier, method.getName(), Type.getMethodDescriptor(method), null, null);
    mv.visitCode();
    // push try/catch block, to catch declared exceptions, and to catch java.lang.Throwable
    final Label l0 = new Label();
    final Label l1 = new Label();
    final Label l2 = new Label();
    if (exceptionTypes.length > 0) {
        mv.visitTryCatchBlock(l0, l1, l2, "java/lang/reflect/InvocationTargetException");
    }
    // push try code
    mv.visitLabel(l0);
    final String classNameToOverride = method.getDeclaringClass().getName().replace('.', '/');
    mv.visitLdcInsn(Type.getType("L" + classNameToOverride + ";"));
    // the following code generates the bytecode for this line of Java:
    // Method method = <proxy>.class.getMethod("add", new Class[] { <array of function argument classes> });
    // get the method name to invoke, and push to stack
    mv.visitLdcInsn(method.getName());
    // create the Class[]
    createArrayDefinition(mv, parameterTypes.length, Class.class);
    int length = 1;
    // push parameters into array
    for (int i = 0; i < parameterTypes.length; i++) {
        // keep copy of array on stack
        mv.visitInsn(DUP);
        Class<?> parameterType = parameterTypes[i];
        // push number onto stack
        pushIntOntoStack(mv, i);
        if (parameterType.isPrimitive()) {
            String wrapperType = getWrapperType(parameterType);
            mv.visitFieldInsn(GETSTATIC, wrapperType, "TYPE", "Ljava/lang/Class;");
        } else {
            mv.visitLdcInsn(Type.getType(parameterType));
        }
        mv.visitInsn(AASTORE);
        if (Long.TYPE.equals(parameterType) || Double.TYPE.equals(parameterType)) {
            length += 2;
        } else {
            length++;
        }
    }
    // the following code generates bytecode equivalent to:
    // return ((<returntype>) invocationHandler.invoke(this, {methodIndex}, new Object[] { <function arguments
    // }))[.<primitive>Value()];
    final Label l4 = new Label();
    mv.visitLabel(l4);
    mv.visitVarInsn(ALOAD, 0);
    // get the invocationHandler field from this class
    mv.visitFieldInsn(GETFIELD, proxyClassFileName, FIELD_INTERCEPTOR_HANDLER, Type.getDescriptor(InterceptorHandler.class));
    // add the Method from the static array as first parameter
    mv.visitFieldInsn(GETSTATIC, proxyClassFileName, FIELD_INTERCEPTED_METHODS, Type.getDescriptor(Method[].class));
    // push the methodIndex of the current method
    if (methodIndex < 128) {
        mv.visitIntInsn(BIPUSH, methodIndex);
    } else if (methodIndex < 32267) {
        // for methods > 127 we need to push a short number as index
        mv.visitIntInsn(SIPUSH, methodIndex);
    } else {
        throw new IllegalStateException("Sorry, we only support Classes with 2^15 methods...");
    }
    // and now load the Method from the array
    mv.visitInsn(AALOAD);
    // prepare the parameter array as Object[] and store it on the stack
    pushMethodParameterArray(mv, parameterTypes);
    // invoke the invocationHandler
    mv.visitMethodInsn(INVOKEINTERFACE, Type.getInternalName(InterceptorHandler.class), "invoke", "(Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;", true);
    // cast the result
    mv.visitTypeInsn(CHECKCAST, getCastType(returnType));
    if (returnType.isPrimitive() && (!Void.TYPE.equals(returnType))) {
        // get the primitive value
        mv.visitMethodInsn(INVOKEVIRTUAL, getWrapperType(returnType), getPrimitiveMethod(returnType), "()" + Type.getDescriptor(returnType), false);
    }
    // push return
    mv.visitLabel(l1);
    if (!Void.TYPE.equals(returnType)) {
        mv.visitInsn(getReturnInsn(returnType));
    } else {
        mv.visitInsn(POP);
        mv.visitInsn(RETURN);
    }
    // catch InvocationTargetException
    if (exceptionTypes.length > 0) {
        mv.visitLabel(l2);
        mv.visitVarInsn(ASTORE, length);
        Label l5 = new Label();
        mv.visitLabel(l5);
        for (int i = 0; i < exceptionTypes.length; i++) {
            Class<?> exceptionType = exceptionTypes[i];
            mv.visitLdcInsn(Type.getType("L" + exceptionType.getCanonicalName().replace('.', '/') + ";"));
            mv.visitVarInsn(ALOAD, length);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/reflect/InvocationTargetException", "getCause", "()Ljava/lang/Throwable;", false);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Object", "getClass", "()Ljava/lang/Class;", false);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Object", "equals", "(Ljava/lang/Object;)Z", false);
            final Label l6 = new Label();
            mv.visitJumpInsn(IFEQ, l6);
            final Label l7 = new Label();
            mv.visitLabel(l7);
            mv.visitVarInsn(ALOAD, length);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/reflect/InvocationTargetException", "getCause", "()Ljava/lang/Throwable;", false);
            mv.visitTypeInsn(CHECKCAST, getCastType(exceptionType));
            mv.visitInsn(ATHROW);
            mv.visitLabel(l6);
            if (i == (exceptionTypes.length - 1)) {
                mv.visitTypeInsn(NEW, "java/lang/reflect/UndeclaredThrowableException");
                mv.visitInsn(DUP);
                mv.visitVarInsn(ALOAD, length);
                mv.visitMethodInsn(INVOKESPECIAL, "java/lang/reflect/UndeclaredThrowableException", "<init>", "(Ljava/lang/Throwable;)V", false);
                mv.visitInsn(ATHROW);
            }
        }
    }
    // finish this method
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

Example 9 with ClassWriter

use of org.apache.xbean.asm6.ClassWriter in project component-runtime by Talend.

the class RepositoryModelBuilderTest method createChainPlugin.

private File createChainPlugin(final File dir, final String plugin) {
    final File target = new File(dir, plugin);
    try (final JarOutputStream outputStream = new JarOutputStream(new FileOutputStream(target))) {
        final String packageName = toPackage(target.getParentFile().getParentFile().getName()).replace(".", "/");
        final String sourcePackage = "org/talend/test";
        final String fromPack = sourcePackage.replace('/', '.');
        final String toPack = packageName.replace('.', '/');
        final File root = new File(jarLocation(getClass()), sourcePackage);
        ofNullable(root.listFiles()).map(Stream::of).orElseGet(Stream::empty).filter(c -> c.getName().endsWith(".class")).forEach(clazz -> {
            try (final InputStream is = new FileInputStream(clazz)) {
                final ClassReader reader = new ClassReader(is);
                final ClassWriter writer = new ClassWriter(COMPUTE_FRAMES);
                reader.accept(new ClassRemapper(writer, new Remapper() {

                    @Override
                    public String map(final String key) {
                        return key.replace(sourcePackage, toPack).replace(fromPack, packageName);
                    }
                }), EXPAND_FRAMES);
                outputStream.putNextEntry(new JarEntry(toPack + '/' + clazz.getName()));
                outputStream.write(writer.toByteArray());
            } catch (final IOException e) {
                fail(e.getMessage());
            }
        });
    } catch (final IOException e) {
        throw new IllegalStateException(e);
    }
    return target;
}

Example 10 with ClassWriter

use of org.apache.xbean.asm6.ClassWriter in project tomee by apache.

the class ValidationGenerator method generate.

public byte[] generate() throws ProxyGenerationException {
    generatedMethods.clear();
    final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
    final String generatedClassName = getName().replace('.', '/');
    cw.visit(V1_8, ACC_PUBLIC + ACC_SUPER, generatedClassName, null, "java/lang/Object", null);
    {
        // public constructor
        final MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        mv.visitVarInsn(ALOAD, 0);
        mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
        mv.visitInsn(RETURN);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    generateMethods(cw);
    /**
     * Read all parent classes and copy the public methods we need
     * into our new class.
     */
    Class current = clazz;
    while (current != null && !current.equals(Object.class)) {
        try {
            final ClassReader classReader = new ClassReader(DynamicSubclass.readClassFile(current));
            classReader.accept(new CopyMethodAnnotations(), ClassReader.SKIP_CODE);
        } catch (final IOException e) {
            throw new ProxyGenerationException(e);
        }
        current = current.getSuperclass();
    }
    return cw.toByteArray();
}