1 /*
  2  * Copyright (c) 2007, 2020, 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.  Oracle designates this
  8  * particular file as subject to the "Classpath" exception as provided
  9  * by Oracle in the LICENSE file that accompanied this code.
 10  *
 11  * This code is distributed in the hope that it will be useful, but WITHOUT
 12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 14  * version 2 for more details (a copy is included in the LICENSE file that
 15  * accompanied this code).
 16  *
 17  * You should have received a copy of the GNU General Public License version
 18  * 2 along with this work; if not, write to the Free Software Foundation,
 19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 20  *
 21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 22  * or visit www.oracle.com if you need additional information or have any
 23  * questions.
 24  */
 25 
 26 package com.sun.tools.classfile;
 27 
 28 import java.io.IOException;
 29 import java.lang.reflect.Constructor;
 30 import java.util.HashMap;
 31 import java.util.Map;
 32 
 33 /**
 34  *  <p><b>This is NOT part of any supported API.
 35  *  If you write code that depends on this, you do so at your own risk.
 36  *  This code and its internal interfaces are subject to change or
 37  *  deletion without notice.</b>
 38  */
 39 
 40 public abstract class Attribute {
 41     public static final String AnnotationDefault        = "AnnotationDefault";
 42     public static final String BootstrapMethods         = "BootstrapMethods";
 43     public static final String CharacterRangeTable      = "CharacterRangeTable";
 44     public static final String Code                     = "Code";
 45     public static final String ConstantValue            = "ConstantValue";
 46     public static final String CompilationID            = "CompilationID";
 47     public static final String Deprecated               = "Deprecated";
 48     public static final String EnclosingMethod          = "EnclosingMethod";
 49     public static final String Exceptions               = "Exceptions";
 50     public static final String InnerClasses             = "InnerClasses";
 51     public static final String JavaFlags                = "JavaFlags";
 52     public static final String LineNumberTable          = "LineNumberTable";
 53     public static final String LocalVariableTable       = "LocalVariableTable";
 54     public static final String LocalVariableTypeTable   = "LocalVariableTypeTable";
 55     public static final String MethodParameters         = "MethodParameters";
 56     public static final String Module                   = "Module";
 57     public static final String ModuleHashes             = "ModuleHashes";
 58     public static final String ModuleMainClass          = "ModuleMainClass";
 59     public static final String ModulePackages           = "ModulePackages";
 60     public static final String ModuleResolution         = "ModuleResolution";
 61     public static final String ModuleTarget             = "ModuleTarget";
 62     public static final String NestHost                 = "NestHost";
 63     public static final String NestMembers              = "NestMembers";
 64     public static final String Record                   = "Record";
 65     public static final String RuntimeVisibleAnnotations = "RuntimeVisibleAnnotations";
 66     public static final String RuntimeInvisibleAnnotations = "RuntimeInvisibleAnnotations";
 67     public static final String RuntimeVisibleParameterAnnotations = "RuntimeVisibleParameterAnnotations";
 68     public static final String RuntimeInvisibleParameterAnnotations = "RuntimeInvisibleParameterAnnotations";
 69     public static final String RuntimeVisibleTypeAnnotations = "RuntimeVisibleTypeAnnotations";
 70     public static final String RuntimeInvisibleTypeAnnotations = "RuntimeInvisibleTypeAnnotations";
 71     public static final String PermittedSubclasses      = "PermittedSubclasses";
 72     public static final String Signature                = "Signature";
 73     public static final String SourceDebugExtension     = "SourceDebugExtension";
 74     public static final String SourceFile               = "SourceFile";
 75     public static final String SourceID                 = "SourceID";
 76     public static final String StackMap                 = "StackMap";
 77     public static final String StackMapTable            = "StackMapTable";
 78     public static final String Synthetic                = "Synthetic";
 79 
 80     public static class Factory {
 81         public Factory() {
 82             // defer init of standardAttributeClasses until after options set up
 83         }
 84 
 85         public Attribute createAttribute(ClassReader cr, int name_index, byte[] data)
 86                 throws IOException {
 87             if (standardAttributes == null) {
 88                 init();
 89             }
 90 
 91             ConstantPool cp = cr.getConstantPool();
 92             String reasonForDefaultAttr;
 93             try {
 94                 String name = cp.getUTF8Value(name_index);
 95                 Class<? extends Attribute> attrClass = standardAttributes.get(name);
 96                 if (attrClass != null) {
 97                     try {
 98                         Class<?>[] constrArgTypes = {ClassReader.class, int.class, int.class};
 99                         Constructor<? extends Attribute> constr = attrClass.getDeclaredConstructor(constrArgTypes);
100                         return constr.newInstance(cr, name_index, data.length);
101                     } catch (Throwable t) {
102                         reasonForDefaultAttr = t.toString();
103                         // fall through and use DefaultAttribute
104                         // t.printStackTrace();
105                     }
106                 } else {
107                     reasonForDefaultAttr = "unknown attribute";
108                 }
109             } catch (ConstantPoolException e) {
110                 reasonForDefaultAttr = e.toString();
111                 // fall through and use DefaultAttribute
112             }
113             return new DefaultAttribute(cr, name_index, data, reasonForDefaultAttr);
114         }
115 
116         protected void init() {
117             standardAttributes = new HashMap<>();
118             standardAttributes.put(AnnotationDefault, AnnotationDefault_attribute.class);
119             standardAttributes.put(BootstrapMethods,  BootstrapMethods_attribute.class);
120             standardAttributes.put(CharacterRangeTable, CharacterRangeTable_attribute.class);
121             standardAttributes.put(Code,              Code_attribute.class);
122             standardAttributes.put(CompilationID,     CompilationID_attribute.class);
123             standardAttributes.put(ConstantValue,     ConstantValue_attribute.class);
124             standardAttributes.put(Deprecated,        Deprecated_attribute.class);
125             standardAttributes.put(EnclosingMethod,   EnclosingMethod_attribute.class);
126             standardAttributes.put(Exceptions,        Exceptions_attribute.class);
127             standardAttributes.put(InnerClasses,      InnerClasses_attribute.class);
128             standardAttributes.put(JavaFlags,         JavaFlags_attribute.class);
129             standardAttributes.put(LineNumberTable,   LineNumberTable_attribute.class);
130             standardAttributes.put(LocalVariableTable, LocalVariableTable_attribute.class);
131             standardAttributes.put(LocalVariableTypeTable, LocalVariableTypeTable_attribute.class);
132             standardAttributes.put(MethodParameters,  MethodParameters_attribute.class);
133             standardAttributes.put(Module,            Module_attribute.class);
134             standardAttributes.put(ModuleHashes,      ModuleHashes_attribute.class);
135             standardAttributes.put(ModuleMainClass,   ModuleMainClass_attribute.class);
136             standardAttributes.put(ModulePackages,    ModulePackages_attribute.class);
137             standardAttributes.put(ModuleResolution,  ModuleResolution_attribute.class);
138             standardAttributes.put(ModuleTarget,      ModuleTarget_attribute.class);
139             standardAttributes.put(NestHost, NestHost_attribute.class);
140             standardAttributes.put(NestMembers, NestMembers_attribute.class);
141             standardAttributes.put(Record, Record_attribute.class);
142             standardAttributes.put(RuntimeInvisibleAnnotations, RuntimeInvisibleAnnotations_attribute.class);
143             standardAttributes.put(RuntimeInvisibleParameterAnnotations, RuntimeInvisibleParameterAnnotations_attribute.class);
144             standardAttributes.put(RuntimeVisibleAnnotations, RuntimeVisibleAnnotations_attribute.class);
145             standardAttributes.put(RuntimeVisibleParameterAnnotations, RuntimeVisibleParameterAnnotations_attribute.class);
146             standardAttributes.put(RuntimeVisibleTypeAnnotations, RuntimeVisibleTypeAnnotations_attribute.class);
147             standardAttributes.put(RuntimeInvisibleTypeAnnotations, RuntimeInvisibleTypeAnnotations_attribute.class);
148             standardAttributes.put(PermittedSubclasses, PermittedSubclasses_attribute.class);
149             standardAttributes.put(Signature,         Signature_attribute.class);
150             standardAttributes.put(SourceDebugExtension, SourceDebugExtension_attribute.class);
151             standardAttributes.put(SourceFile,        SourceFile_attribute.class);
152             standardAttributes.put(SourceID,          SourceID_attribute.class);
153             standardAttributes.put(StackMap,          StackMap_attribute.class);
154             standardAttributes.put(StackMapTable,     StackMapTable_attribute.class);
155             standardAttributes.put(Synthetic,         Synthetic_attribute.class);
156         }
157 
158         private Map<String,Class<? extends Attribute>> standardAttributes;
159     }
160 
161     public static Attribute read(ClassReader cr) throws IOException {
162         return cr.readAttribute();
163     }
164 
165     protected Attribute(int name_index, int length) {
166         attribute_name_index = name_index;
167         attribute_length = length;
168     }
169 
170     public String getName(ConstantPool constant_pool) throws ConstantPoolException {
171         return constant_pool.getUTF8Value(attribute_name_index);
172     }
173 
174     public abstract <R,D> R accept(Attribute.Visitor<R,D> visitor, D data);
175 
176     public int byteLength() {
177         return 6 + attribute_length;
178     }
179 
180     public final int attribute_name_index;
181     public final int attribute_length;
182 
183 
184     public interface Visitor<R,P> {
185         R visitBootstrapMethods(BootstrapMethods_attribute attr, P p);
186         R visitDefault(DefaultAttribute attr, P p);
187         R visitAnnotationDefault(AnnotationDefault_attribute attr, P p);
188         R visitCharacterRangeTable(CharacterRangeTable_attribute attr, P p);
189         R visitCode(Code_attribute attr, P p);
190         R visitCompilationID(CompilationID_attribute attr, P p);
191         R visitConstantValue(ConstantValue_attribute attr, P p);
192         R visitDeprecated(Deprecated_attribute attr, P p);
193         R visitEnclosingMethod(EnclosingMethod_attribute attr, P p);
194         R visitExceptions(Exceptions_attribute attr, P p);
195         R visitInnerClasses(InnerClasses_attribute attr, P p);
196         R visitJavaFlags(JavaFlags_attribute attr, P p);
197         R visitLineNumberTable(LineNumberTable_attribute attr, P p);
198         R visitLocalVariableTable(LocalVariableTable_attribute attr, P p);
199         R visitLocalVariableTypeTable(LocalVariableTypeTable_attribute attr, P p);
200         R visitMethodParameters(MethodParameters_attribute attr, P p);
201         R visitModule(Module_attribute attr, P p);
202         R visitModuleHashes(ModuleHashes_attribute attr, P p);
203         R visitModuleMainClass(ModuleMainClass_attribute attr, P p);
204         R visitModulePackages(ModulePackages_attribute attr, P p);
205         R visitModuleResolution(ModuleResolution_attribute attr, P p);
206         R visitModuleTarget(ModuleTarget_attribute attr, P p);
207         R visitNestHost(NestHost_attribute attr, P p);
208         R visitNestMembers(NestMembers_attribute attr, P p);
209         R visitRecord(Record_attribute attr, P p);
210         R visitRuntimeVisibleAnnotations(RuntimeVisibleAnnotations_attribute attr, P p);
211         R visitRuntimeInvisibleAnnotations(RuntimeInvisibleAnnotations_attribute attr, P p);
212         R visitRuntimeVisibleParameterAnnotations(RuntimeVisibleParameterAnnotations_attribute attr, P p);
213         R visitRuntimeInvisibleParameterAnnotations(RuntimeInvisibleParameterAnnotations_attribute attr, P p);
214         R visitRuntimeVisibleTypeAnnotations(RuntimeVisibleTypeAnnotations_attribute attr, P p);
215         R visitRuntimeInvisibleTypeAnnotations(RuntimeInvisibleTypeAnnotations_attribute attr, P p);
216         R visitPermittedSubclasses(PermittedSubclasses_attribute attr, P p);
217         R visitSignature(Signature_attribute attr, P p);
218         R visitSourceDebugExtension(SourceDebugExtension_attribute attr, P p);
219         R visitSourceFile(SourceFile_attribute attr, P p);
220         R visitSourceID(SourceID_attribute attr, P p);
221         R visitStackMap(StackMap_attribute attr, P p);
222         R visitStackMapTable(StackMapTable_attribute attr, P p);
223         R visitSynthetic(Synthetic_attribute attr, P p);
224     }
225 }