| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.drill.exec.compile; |
| |
| import org.objectweb.asm.ClassVisitor; |
| import org.objectweb.asm.Opcodes; |
| |
| /** |
| * An ASM ClassVisitor that strips class the access bits that are only possible |
| * on inner classes (ACC_PROTECTED, ACC_PRIVATE, and ACC_FINAL). These bits are |
| * only stripped from the class' visit() call if the class' name contains a |
| * '$'. |
| * |
| * <p>This visitor is meant to be used on classes that will undergo validation |
| * with CheckClassAdapter. CheckClassAdapter assumes it will only be called on |
| * non-inner classes, and throws an IllegalArgumentException if the class is |
| * protected, private, or final. However, once classes are compiled, they appear |
| * in their class files alone, and these options may be present, with no way |
| * for an outside observer to tell if they were originally inner classes. |
| */ |
| public class InnerClassAccessStripper extends ClassVisitor { |
| private int originalClassAccess; |
| private boolean accessCaptured; |
| |
| /** |
| * See {@link org.objectweb.asm.ClassVisitor#ClassVisitor(int)}. |
| */ |
| public InnerClassAccessStripper(final int api) { |
| super(api); |
| } |
| |
| /** |
| * See {@link org.objectweb.asm.ClassVisitor#ClassVisitor(int, ClassVisitor)}. |
| */ |
| public InnerClassAccessStripper(final int api, final ClassVisitor cv) { |
| super(api, cv); |
| } |
| |
| /** |
| * Return the original class' access bits. |
| * |
| * <p>This may only be called after {@link ClassVisitor#visit(int, int, String, String, String, String[])} |
| * has been called; that's where the bits are stripped and captured. |
| * |
| * @return the original class bits |
| * @throws IllegalStateException if visit() hasn't been called yet |
| */ |
| public int getOriginalAccess() { |
| if (!accessCaptured) { |
| throw new IllegalStateException( |
| "can't get original access before it is captured"); |
| } |
| |
| return originalClassAccess; |
| } |
| |
| @Override |
| public void visit(final int version, final int access, final String name, |
| final String signature, final String superName, final String[] interfaces) { |
| /* |
| * Record the original access bits so we can restore them before the next |
| * link in the visitor chain. |
| */ |
| originalClassAccess = access; |
| accessCaptured = true; |
| |
| // If we're checking an inner class, suppress access bits that ASM chokes on. |
| int checkClassAccess = access; |
| if (name.indexOf('$') >= 0) { |
| checkClassAccess &= ~(Opcodes.ACC_PROTECTED | Opcodes.ACC_PRIVATE | Opcodes.ACC_STATIC); |
| } |
| super.visit(version, checkClassAccess, name, signature, superName, interfaces); |
| } |
| } |