1 // ASM: a very small and fast Java bytecode manipulation framework 2 // Copyright (c) 2000-2011 INRIA, France Telecom 3 // All rights reserved. 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions 7 // are met: 8 // 1. Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // 2. Redistributions in binary form must reproduce the above copyright 11 // notice, this list of conditions and the following disclaimer in the 12 // documentation and/or other materials provided with the distribution. 13 // 3. Neither the name of the copyright holders nor the names of its 14 // contributors may be used to endorse or promote products derived from 15 // this software without specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 27 // THE POSSIBILITY OF SUCH DAMAGE. 28 package org.objectweb.asm.util; 29 30 import org.objectweb.asm.AnnotationVisitor; 31 import org.objectweb.asm.Attribute; 32 import org.objectweb.asm.FieldVisitor; 33 import org.objectweb.asm.Opcodes; 34 import org.objectweb.asm.TypePath; 35 import org.objectweb.asm.TypeReference; 36 37 /** 38 * A {@link FieldVisitor} that checks that its methods are properly used. 39 * 40 * @author Eric Bruneton 41 */ 42 public class CheckFieldAdapter extends FieldVisitor { 43 44 /** Whether the {@link #visitEnd} method has been called. */ 45 private boolean visitEndCalled; 46 47 /** 48 * Constructs a new {@link CheckFieldAdapter}. <i>Subclasses must not use this constructor</i>. 49 * Instead, they must use the {@link #CheckFieldAdapter(int, FieldVisitor)} version. 50 * 51 * @param fieldVisitor the field visitor to which this adapter must delegate calls. 52 * @throws IllegalStateException If a subclass calls this constructor. 53 */ CheckFieldAdapter(final FieldVisitor fieldVisitor)54 public CheckFieldAdapter(final FieldVisitor fieldVisitor) { 55 this(/* latest api = */ Opcodes.ASM9, fieldVisitor); 56 if (getClass() != CheckFieldAdapter.class) { 57 throw new IllegalStateException(); 58 } 59 } 60 61 /** 62 * Constructs a new {@link CheckFieldAdapter}. 63 * 64 * @param api the ASM API version implemented by this visitor. Must be one of the {@code 65 * ASM}<i>x</i> values in {@link Opcodes}. 66 * @param fieldVisitor the field visitor to which this adapter must delegate calls. 67 */ CheckFieldAdapter(final int api, final FieldVisitor fieldVisitor)68 protected CheckFieldAdapter(final int api, final FieldVisitor fieldVisitor) { 69 super(api, fieldVisitor); 70 } 71 72 @Override visitAnnotation(final String descriptor, final boolean visible)73 public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) { 74 checkVisitEndNotCalled(); 75 // Annotations can only appear in V1_5 or more classes. 76 CheckMethodAdapter.checkDescriptor(Opcodes.V1_5, descriptor, false); 77 return new CheckAnnotationAdapter(super.visitAnnotation(descriptor, visible)); 78 } 79 80 @Override visitTypeAnnotation( final int typeRef, final TypePath typePath, final String descriptor, final boolean visible)81 public AnnotationVisitor visitTypeAnnotation( 82 final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) { 83 checkVisitEndNotCalled(); 84 int sort = new TypeReference(typeRef).getSort(); 85 if (sort != TypeReference.FIELD) { 86 throw new IllegalArgumentException( 87 "Invalid type reference sort 0x" + Integer.toHexString(sort)); 88 } 89 CheckClassAdapter.checkTypeRef(typeRef); 90 CheckMethodAdapter.checkDescriptor(Opcodes.V1_5, descriptor, false); 91 return new CheckAnnotationAdapter( 92 super.visitTypeAnnotation(typeRef, typePath, descriptor, visible)); 93 } 94 95 @Override visitAttribute(final Attribute attribute)96 public void visitAttribute(final Attribute attribute) { 97 checkVisitEndNotCalled(); 98 if (attribute == null) { 99 throw new IllegalArgumentException("Invalid attribute (must not be null)"); 100 } 101 super.visitAttribute(attribute); 102 } 103 104 @Override visitEnd()105 public void visitEnd() { 106 checkVisitEndNotCalled(); 107 visitEndCalled = true; 108 super.visitEnd(); 109 } 110 checkVisitEndNotCalled()111 private void checkVisitEndNotCalled() { 112 if (visitEndCalled) { 113 throw new IllegalStateException("Cannot call a visit method after visitEnd has been called"); 114 } 115 } 116 } 117