|
1
52
53 package com.go.trove.classfile;
54
55 import java.util.*;
56 import java.io.*;
57
58
70 public class CodeAttr extends Attribute {
71 private CodeBuffer mCodeBuffer;
72 private List mAttributes = new ArrayList(2);
73
74 private LineNumberTableAttr mLineNumberTable;
75 private LocalVariableTableAttr mLocalVariableTable;
76
77 CodeAttr(ConstantPool cp) {
78 super(cp, CODE);
79 }
80
81
84 public CodeBuffer getCodeBuffer() {
85 return mCodeBuffer;
86 }
87
88 public void setCodeBuffer(CodeBuffer code) {
89 mCodeBuffer = code;
90 }
91
92
98 public int getLineNumber(Location start) {
99 if (mLineNumberTable == null || start.getLocation() < 0) {
100 return -1;
101 }
102 else {
103 return mLineNumberTable.getLineNumber(start);
104 }
105 }
106
107
111 public void mapLineNumber(Location start, int line_number) {
112 if (mLineNumberTable == null) {
113 addAttribute(new LineNumberTableAttr(mCp));
114 }
115
116 mLineNumberTable.addEntry(start, line_number);
117 }
118
119
125 public void localVariableUse(LocalVariable localVar) {
126 if (mLocalVariableTable == null) {
127 addAttribute(new LocalVariableTableAttr(mCp));
128 }
129
130 mLocalVariableTable.addEntry(localVar);
131 }
132
133 public void addAttribute(Attribute attr) {
134 if (attr instanceof LineNumberTableAttr) {
135 if (mLineNumberTable != null) {
136 mAttributes.remove(mLineNumberTable);
137 }
138 mLineNumberTable = (LineNumberTableAttr)attr;
139 }
140 else if (attr instanceof LocalVariableTableAttr) {
141 if (mLocalVariableTable != null) {
142 mAttributes.remove(mLocalVariableTable);
143 }
144 mLocalVariableTable = (LocalVariableTableAttr)attr;
145 }
146
147 mAttributes.add(attr);
148 }
149
150 public Attribute[] getAttributes() {
151 Attribute[] attrs = new Attribute[mAttributes.size()];
152 return (Attribute[])mAttributes.toArray(attrs);
153 }
154
155
158 public int getLength() {
159 int length = 12;
160
161 if (mCodeBuffer != null) {
162 length += mCodeBuffer.getByteCodes().length;
163 ExceptionHandler[] handlers = mCodeBuffer.getExceptionHandlers();
164 if (handlers != null) {
165 length += 8 * handlers.length;
166 }
167 }
168
169 int size = mAttributes.size();
170 for (int i=0; i<size; i++) {
171 length += ((Attribute)mAttributes.get(i)).getLength();
172 length += 6; }
174
175 return length;
176 }
177
178 public void writeDataTo(DataOutput dout) throws IOException {
179 if (mCodeBuffer == null) {
180 throw new NullPointerException  ("CodeAttr has no CodeBuffer set");
181 }
182
183 ExceptionHandler[] handlers = mCodeBuffer.getExceptionHandlers();
184
185 dout.writeShort(mCodeBuffer.getMaxStackDepth());
186 dout.writeShort(mCodeBuffer.getMaxLocals());
187
188 byte[] byteCodes = mCodeBuffer.getByteCodes();
189 dout.writeInt(byteCodes.length);
190 dout.write(byteCodes);
191
192 if (handlers != null) {
193 int exceptionHandlerCount = handlers.length;
194 dout.writeShort(exceptionHandlerCount);
195
196 for (int i=0; i<exceptionHandlerCount; i++) {
197 handlers[i].writeTo(dout);
198 }
199 }
200 else {
201 dout.writeShort(0);
202 }
203
204 int size = mAttributes.size();
205 dout.writeShort(size);
206 for (int i=0; i<size; i++) {
207 Attribute attr = (Attribute)mAttributes.get(i);
208 attr.writeTo(dout);
209 }
210 }
211
212 static Attribute define(ConstantPool cp,
213 String name,
214 int length,
215 DataInput din,
216 AttributeFactory attrFactory)
217 throws IOException
218 {
219 CodeAttr code = new CodeAttr(cp);
220
221 final int maxStackDepth = din.readUnsignedShort();
222 final int maxLocals = din.readUnsignedShort();
223
224 final byte[] byteCodes = new byte[din.readInt()];
225 din.readFully(byteCodes);
226
227 int exceptionHandlerCount = din.readUnsignedShort();
228 final ExceptionHandler[] handlers =
229 new ExceptionHandler[exceptionHandlerCount];
230
231 for (int i=0; i<exceptionHandlerCount; i++) {
232 handlers[i] = ExceptionHandler.readFrom(cp, din);
233 }
234
235 code.mCodeBuffer = new CodeBuffer() {
236 public int getMaxStackDepth() {
237 return maxStackDepth;
238 }
239
240 public int getMaxLocals() {
241 return maxLocals;
242 }
243
244 public byte[] getByteCodes() {
245 return (byte[])byteCodes.clone();
246 }
247
248 public ExceptionHandler[] getExceptionHandlers() {
249 return (ExceptionHandler[])handlers.clone();
250 }
251 };
252
253 int attributeCount = din.readUnsignedShort();
254 for (int i=0; i<attributeCount; i++) {
255 code.addAttribute(Attribute.readFrom(cp, din, attrFactory));
256 }
257
258 return code;
259 }
260 }
261 |
Popular Tags |
Java API By Example, From Geeks To Geeks.