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1
16
17 package org.cojen.classfile.attribute;
18
19 import java.util.ArrayList  ;
20 import java.util.Collections ;
21 import java.util.HashSet ;
22 import java.util.Iterator ;
23 import java.util.List ;
24 import java.util.Set ;
25 import java.io.DataInput ;
26 import java.io.DataOutput ;
27 import java.io.IOException ;
28 import org.cojen.classfile.Attribute;
29 import org.cojen.classfile.ConstantPool;
30 import org.cojen.classfile.FixedLocation;
31 import org.cojen.classfile.LocalVariable;
32 import org.cojen.classfile.Location;
33 import org.cojen.classfile.LocationRange;
34 import org.cojen.classfile.LocationRangeImpl;
35 import org.cojen.classfile.TypeDesc;
36 import org.cojen.classfile.constant.ConstantUTFInfo;
37
38
44 public class LocalVariableTableAttr extends Attribute {
45
46 private List mEntries = new ArrayList (10);
47 private List mCleanEntries;
48 private int mRangeCount;
49
50 public LocalVariableTableAttr(ConstantPool cp) {
51 super(cp, LOCAL_VARIABLE_TABLE);
52 }
53
54 public LocalVariableTableAttr(ConstantPool cp, String name) {
55 super(cp, name);
56 }
57
58 public LocalVariableTableAttr(ConstantPool cp, String name, int length, DataInput din)
59 throws IOException
60 {
61 super(cp, name);
62
63 int size = din.readUnsignedShort();
64 for (int i=0; i<size; i++) {
65 int start_pc = din.readUnsignedShort();
66 int end_pc = start_pc + din.readUnsignedShort() + 1;
67 int name_index = din.readUnsignedShort();
68 int descriptor_index = din.readUnsignedShort();
69 final int index = din.readUnsignedShort();
70
71 final ConstantUTFInfo varName =
72 (ConstantUTFInfo)cp.getConstant(name_index);
73 final ConstantUTFInfo varDesc =
74 (ConstantUTFInfo)cp.getConstant(descriptor_index);
75
76 final Location startLocation = new FixedLocation(start_pc);
77 final Location endLocation = new FixedLocation(end_pc);
78
79 Set ranges = new HashSet ();
80 ranges.add(new LocationRangeImpl(startLocation, endLocation));
81 final Set fRanges = Collections.unmodifiableSet(ranges);
82
83 LocalVariable localVar = new LocalVariable() {
84 private String mName;
85 private TypeDesc mType;
86
87 {
88 mName = varName.getValue();
89 mType = TypeDesc.forDescriptor(varDesc.getValue());
90 }
91
92 public String getName() {
93 return mName;
94 }
95
96 public void setName(String name) {
97 mName = name;
98 }
99
100 public TypeDesc getType() {
101 return mType;
102 }
103
104 public boolean isDoubleWord() {
105 return mType.isDoubleWord();
106 }
107
108 public int getNumber() {
109 return index;
110 }
111
112 public Set getLocationRangeSet() {
113 return fRanges;
114 }
115 };
116
117 mEntries.add(new Entry(localVar, varName, varDesc));
118 }
119 }
120
121
124 public void addEntry(LocalVariable localVar) {
125 String varName = localVar.getName();
126 if (varName != null) {
127 ConstantUTFInfo name = getConstantPool().addConstantUTF(varName);
128 ConstantUTFInfo descriptor =
129 getConstantPool().addConstantUTF(localVar.getType().getDescriptor());
130 mEntries.add(new Entry(localVar, name, descriptor));
131 }
132
133 mCleanEntries = null;
134 }
135
136 public int getLength() {
137 clean();
138 return 2 + 10 * mRangeCount;
139 }
140
141 public void writeDataTo(DataOutput dout) throws IOException {
142 dout.writeShort(mRangeCount);
143
144 int size = mCleanEntries.size();
145 for (int i=0; i<size; i++) {
146 Entry entry = (Entry)mEntries.get(i);
147 LocalVariable localVar = entry.mLocalVar;
148
149 Set ranges = localVar.getLocationRangeSet();
150 if (ranges == null) {
151 continue;
152 }
153
154 int name_index = entry.mName.getIndex();
155 int descriptor_index = entry.mDescriptor.getIndex();
156 int index = localVar.getNumber();
157
158 check("local variable table entry name index", name_index);
159 check("local variable table entry descriptor index", descriptor_index);
160 check("local variable table entry index", index);
161
162 Iterator it = ranges.iterator();
163 while (it.hasNext()) {
164 LocationRange range = (LocationRange)it.next();
165
166 Location startLocation = range.getStartLocation();
167 Location endLocation = range.getEndLocation();
168
169 int start_pc = startLocation.getLocation();
170 int length = endLocation.getLocation() - start_pc - 1;
171
172 check("local variable table entry start PC", start_pc);
173
174 dout.writeShort(start_pc);
175 dout.writeShort(length);
176 dout.writeShort(name_index);
177 dout.writeShort(descriptor_index);
178 dout.writeShort(index);
179 }
180 }
181 }
182
183 private void check(String type, int addr) throws IllegalStateException {
184 if (addr < 0 || addr > 65535) {
185 throw new IllegalStateException ("Value for " + type + " out of " +
186 "valid range: " + addr);
187 }
188 }
189
190 private void clean() {
191 if (mCleanEntries != null) {
192 return;
193 }
194
195
197 int size = mEntries.size();
198 mCleanEntries = new ArrayList (size);
199 mRangeCount = 0;
200
201 outer:
202 for (int i=0; i<size; i++) {
203 Entry entry = (Entry)mEntries.get(i);
204 LocalVariable localVar = entry.mLocalVar;
205
206 Set ranges = localVar.getLocationRangeSet();
207 if (ranges == null || ranges.size() == 0) {
208 continue;
209 }
210
211 Iterator it = ranges.iterator();
212 while (it.hasNext()) {
213 LocationRange range = (LocationRange)it.next();
214
215 Location startLocation = range.getStartLocation();
216 Location endLocation = range.getEndLocation();
217
218 if (startLocation == null || endLocation == null) {
219 continue outer;
220 }
221
222 int start_pc = startLocation.getLocation();
223 int length = endLocation.getLocation() - start_pc - 1;
224
225 if (length < 0) {
226 continue outer;
227 }
228 }
229
230 mCleanEntries.add(entry);
231 mRangeCount += entry.getRangeCount();
232 }
233 }
234
235 private static class Entry {
236 public LocalVariable mLocalVar;
237 public ConstantUTFInfo mName;
238 public ConstantUTFInfo mDescriptor;
239
240 public Entry(LocalVariable localVar,
241 ConstantUTFInfo name, ConstantUTFInfo descriptor) {
242
243 mLocalVar = localVar;
244 mName = name;
245 mDescriptor = descriptor;
246 }
247
248 public int getRangeCount() {
249 return mLocalVar.getLocationRangeSet().size();
250 }
251 }
252 }
253 |
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