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1
52
53 package com.go.trove.classfile;
54
55 import java.util.*;
56 import java.io.*;
57
58
66 class LocalVariableTableAttr extends Attribute {
67 private List mEntries = new ArrayList(10);
68 private List mCleanEntries;
69 private int mRangeCount;
70
71 public LocalVariableTableAttr(ConstantPool cp) {
72 super(cp, LOCAL_VARIABLE_TABLE);
73 }
74
75
78 public void addEntry(LocalVariable localVar) {
79 String  varName = localVar.getName();
80 if (varName != null) {
81 ConstantUTFInfo name = ConstantUTFInfo.make(mCp, varName);
82 ConstantUTFInfo descriptor =
83 ConstantUTFInfo.make(mCp, localVar.getType().toString());
84
85 mEntries.add(new Entry(localVar, name, descriptor));
86 }
87
88 mCleanEntries = null;
89 }
90
91 public int getLength() {
92 clean();
93 return 2 + 10 * mRangeCount;
94 }
95
96 public void writeDataTo(DataOutput dout) throws IOException {
97 dout.writeShort(mRangeCount);
98
99 int size = mCleanEntries.size();
100 for (int i=0; i<size; i++) {
101 Entry entry = (Entry)mEntries.get(i);
102 LocalVariable localVar = entry.mLocalVar;
103
104 SortedSet ranges = localVar.getLocationRangeSet();
105
106 int name_index = entry.mName.getIndex();
107 int descriptor_index = entry.mDescriptor.getIndex();
108 int index = localVar.getNumber();
109
110 check("local variable table entry name index", name_index);
111 check("local variable table entry descriptor index",
112 descriptor_index);
113 check("local variable table entry index", index);
114
115 Iterator it = ranges.iterator();
116 while (it.hasNext()) {
117 LocationRange range = (LocationRange)it.next();
118
119 Location startLocation = range.getStartLocation();
120 Location endLocation = range.getEndLocation();
121
122 int start_pc = startLocation.getLocation();
123 int length = endLocation.getLocation() - start_pc - 1;
124
125 check("local variable table entry start PC", start_pc);
126
127 dout.writeShort(start_pc);
128 dout.writeShort(length);
129 dout.writeShort(name_index);
130 dout.writeShort(descriptor_index);
131 dout.writeShort(index);
132 }
133 }
134 }
135
136 private void check(String type, int addr) throws RuntimeException {
137 if (addr < 0 || addr > 65535) {
138 throw new RuntimeException ("Value for " + type + " out of " +
139 "valid range: " + addr);
140 }
141 }
142
143 private void clean() {
144 if (mCleanEntries != null) {
145 return;
146 }
147
148
150 int size = mEntries.size();
151 mCleanEntries = new ArrayList(size);
152 mRangeCount = 0;
153
154 outer:
155 for (int i=0; i<size; i++) {
156 Entry entry = (Entry)mEntries.get(i);
157 LocalVariable localVar = entry.mLocalVar;
158
159 SortedSet ranges = localVar.getLocationRangeSet();
160 if (ranges == null || ranges.size() == 0) {
161 continue;
162 }
163
164 Iterator it = ranges.iterator();
165 while (it.hasNext()) {
166 LocationRange range = (LocationRange)it.next();
167
168 Location startLocation = range.getStartLocation();
169 Location endLocation = range.getEndLocation();
170
171 if (startLocation == null || endLocation == null) {
172 continue outer;
173 }
174
175 int start_pc = startLocation.getLocation();
176 int length = endLocation.getLocation() - start_pc - 1;
177
178 if (length < 0) {
179 continue outer;
180 }
181 }
182
183 mCleanEntries.add(entry);
184 mRangeCount += entry.getRangeCount();
185 }
186 }
187
188 static Attribute define(ConstantPool cp,
189 String name,
190 int length,
191 DataInput din) throws IOException {
192
193 LocalVariableTableAttr locals = new LocalVariableTableAttr(cp);
194
195 int size = din.readUnsignedShort();
196 for (int i=0; i<size; i++) {
197 int start_pc = din.readUnsignedShort();
198 int end_pc = start_pc + din.readUnsignedShort() + 1;
199 int name_index = din.readUnsignedShort();
200 int descriptor_index = din.readUnsignedShort();
201 final int index = din.readUnsignedShort();
202
203 final ConstantUTFInfo varName =
204 (ConstantUTFInfo)cp.getConstant(name_index);
205 final ConstantUTFInfo varDesc =
206 (ConstantUTFInfo)cp.getConstant(descriptor_index);
207
208 final Location startLocation = new FixedLocation(start_pc);
209 final Location endLocation = new FixedLocation(end_pc);
210
211 SortedSet ranges = new TreeSet();
212 ranges.add(new LocationRangeImpl(startLocation, endLocation));
213 final SortedSet fRanges =
214 Collections.unmodifiableSortedSet(ranges);
215
216 LocalVariable localVar = new LocalVariable() {
217 private String mName;
218 private TypeDescriptor mType;
219
220 {
221 mName = varName.getValue();
222 mType = TypeDescriptor.parseTypeDesc(varDesc.getValue());
223 }
224
225 public String getName() {
226 return mName;
227 }
228
229 public void setName(String name) {
230 mName = name;
231 }
232
233 public TypeDescriptor getType() {
234 return mType;
235 }
236
237 public boolean isDoubleWord() {
238 Class clazz = mType.getClassArg();
239 return (clazz == double.class || clazz == long.class);
240 }
241
242 public int getNumber() {
243 return index;
244 }
245
246 public SortedSet getLocationRangeSet() {
247 return fRanges;
248 }
249 };
250
251 Entry entry = new Entry(localVar, varName, varDesc);
252 locals.mEntries.add(entry);
253 }
254
255 return locals;
256 }
257
258 private static class Entry {
259 public LocalVariable mLocalVar;
260 public ConstantUTFInfo mName;
261 public ConstantUTFInfo mDescriptor;
262
263 public Entry(LocalVariable localVar,
264 ConstantUTFInfo name, ConstantUTFInfo descriptor) {
265
266 mLocalVar = localVar;
267 mName = name;
268 mDescriptor = descriptor;
269 }
270
271 public int getRangeCount() {
272 return mLocalVar.getLocationRangeSet().size();
273 }
274 }
275 }
276 |
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