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1
52
53 package com.go.trove.classfile;
54
55 import java.io.*;
56
57
66 public abstract class Attribute {
67 final static Attribute[] NO_ATTRIBUTES = new Attribute[0];
68
69 final static String  CODE = "Code";
70 final static String CONSTANT_VALUE = "ConstantValue";
71 final static String DEPRECATED = "Deprecated";
72 final static String EXCEPTIONS = "Exceptions";
73 final static String INNER_CLASSES = "InnerClasses";
74 final static String LINE_NUMBER_TABLE = "LineNumberTable";
75 final static String LOCAL_VARIABLE_TABLE = "LocalVariableTable";
76 final static String SOURCE_FILE = "SourceFile";
77 final static String SYNTHETIC = "Synthetic";
78
79
80 protected final ConstantPool mCp;
81
82 private String mName;
83 private ConstantUTFInfo mNameConstant;
84
85 protected Attribute(ConstantPool cp, String name) {
86 mCp = cp;
87 mName = name;
88 mNameConstant = ConstantUTFInfo.make(cp, name);
89 }
90
91
94 public ConstantPool getConstantPool() {
95 return mCp;
96 }
97
98
101 public String getName() {
102 return mName;
103 }
104
105 public ConstantUTFInfo getNameConstant() {
106 return mNameConstant;
107 }
108
109
113 public Attribute[] getAttributes() {
114 return NO_ATTRIBUTES;
115 }
116
117
120 public abstract int getLength();
121
122
126 public final void writeTo(DataOutput dout) throws IOException {
127 dout.writeShort(mNameConstant.getIndex());
128 dout.writeInt(getLength());
129 writeDataTo(dout);
130 }
131
132
136 public void writeDataTo(DataOutput dout) throws IOException {
137 }
138
139
142 public static Attribute readFrom(ConstantPool cp,
143 DataInput din,
144 AttributeFactory attrFactory)
145 throws IOException
146 {
147 int index = din.readUnsignedShort();
148 String name = ((ConstantUTFInfo)cp.getConstant(index)).getValue();
149 int length = din.readInt();
150
151 attrFactory = new Factory(attrFactory);
152 return attrFactory.createAttribute(cp, name, length, din);
153 }
154
155 private static class Factory implements AttributeFactory {
156 private final AttributeFactory mAttrFactory;
157
158 public Factory(AttributeFactory attrFactory) {
159 mAttrFactory = attrFactory;
160 }
161
162 public Attribute createAttribute(ConstantPool cp,
163 String name,
164 final int length,
165 DataInput din) throws IOException {
166 if (name.equals(CODE)) {
167 return CodeAttr.define(cp, name, length, din, mAttrFactory);
168 }
169 else if (name.equals(CONSTANT_VALUE)) {
170 return ConstantValueAttr.define(cp, name, length, din);
171 }
172 else if (name.equals(DEPRECATED)) {
173 return DeprecatedAttr.define(cp, name, length, din);
174 }
175 else if (name.equals(EXCEPTIONS)) {
176 return ExceptionsAttr.define(cp, name, length, din);
177 }
178 else if (name.equals(INNER_CLASSES)) {
179 return InnerClassesAttr.define(cp, name, length, din);
180 }
181 else if (name.equals(LINE_NUMBER_TABLE)) {
182 return LineNumberTableAttr.define(cp, name, length, din);
183 }
184 else if (name.equals(LOCAL_VARIABLE_TABLE)) {
185 return LocalVariableTableAttr.define
186 (cp, name, length, din);
187 }
188 else if (name.equals(SOURCE_FILE)) {
189 return SourceFileAttr.define(cp, name, length, din);
190 }
191 else if (name.equals(SYNTHETIC)) {
192 return SyntheticAttr.define(cp, name, length, din);
193 }
194
195 if (mAttrFactory != null) {
196 Attribute attr =
197 mAttrFactory.createAttribute(cp, name, length, din);
198 if (attr != null) {
199 return attr;
200 }
201 }
202
203
206 final byte[] data = new byte[length];
207 din.readFully(data);
208
209 return new Attribute(cp, name) {
210 public int getLength() {
211 return length;
212 }
213
214 public void writeDataTo(DataOutput dout) throws IOException {
215 dout.write(data);
216 }
217 };
218 }
219 }
220 }
221 |
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