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1
25
26 package org.netbeans.modules.classfile;
27
28 import java.io.*;
29 import java.util.*;
30
31
36 public final class ConstantPool {
37
38 private static final int CONSTANT_POOL_START = 1;
39
40 static final int CONSTANT_Utf8 = 1;
42 static final int CONSTANT_Integer = 3;
43 static final int CONSTANT_Float = 4;
44 static final int CONSTANT_Long = 5;
45 static final int CONSTANT_Double = 6;
46 static final int CONSTANT_Class = 7;
47 static final int CONSTANT_String = 8;
48 static final int CONSTANT_FieldRef = 9;
49 static final int CONSTANT_MethodRef = 10;
50 static final int CONSTANT_InterfaceMethodRef = 11;
51 static final int CONSTANT_NameAndType = 12;
52
53 CPEntry[] cpEntries;
54
55 int constantPoolCount = 0;
56
57
63 ConstantPool(int size, InputStream bytes)
64 throws IOException {
65 if (size < 0)
66 throw new IllegalArgumentException  ("size cannot be negative");
67 if (bytes == null)
68 throw new IllegalArgumentException ("byte stream not specified");
69 constantPoolCount = size;
70 cpEntries = new CPEntry[constantPoolCount];
71 load(bytes);
72 }
73
74
78 ConstantPool() {
79 constantPoolCount = CONSTANT_POOL_START;
80 cpEntries = new CPEntry[constantPoolCount];
81 }
82
83
88 public final CPEntry get(int index) {
89 if (index <= 0 || index >= cpEntries.length)
90 throw new IndexOutOfBoundsException (Integer.toString(index));
91 return cpEntries[index];
92 }
93
94
99 public final CPClassInfo getClass(int index) {
100 if (index <= 0)
101 throw new IndexOutOfBoundsException (Integer.toString(index));
102 return (CPClassInfo)get(index);
103 }
104
105
109 public final Collection getAllConstants(Class classType) {
110 return Collections.unmodifiableCollection(
111 getAllConstantsImpl(classType));
112 }
113
114 private Collection<CPEntry> getAllConstantsImpl(Class classType) {
115 int n = cpEntries.length;
116 Collection<CPEntry> c = new ArrayList<CPEntry>(n);
117 for (int i = CONSTANT_POOL_START; i < n; i++) {
118 if (cpEntries[i] != null &&
119 cpEntries[i].getClass().equals(classType)) {
120 c.add(cpEntries[i]);
121 }
122 }
123 return c;
124 }
125
126
134 public final Set getAllClassNames() {
135 Set<ClassName> set = new HashSet<ClassName>();
136
137 Collection c = getAllConstantsImpl(CPClassInfo.class);
139 for (Iterator i = c.iterator(); i.hasNext();) {
140 CPClassInfo ci = (CPClassInfo)i.next();
141 set.add(ci.getClassName());
142 }
143 return Collections.unmodifiableSet(set);
144 }
145
146 final String getString(int index) {
147 CPUTF8Info utf = (CPUTF8Info)cpEntries[index];
148 return utf.getName();
149 }
150
151 private void load(InputStream cpBytes) throws IOException {
152 try {
153 ConstantPoolReader cpr = new ConstantPoolReader(cpBytes);
154
155 for (int i = CONSTANT_POOL_START; i < constantPoolCount; i++) {
157 CPEntry newEntry = getConstantPoolEntry(cpr);
158 cpEntries[i] = newEntry;
159
160 if (newEntry.usesTwoSlots())
161 i++;
162 }
163
164 for (int i = CONSTANT_POOL_START; i < constantPoolCount; i++) {
166 CPEntry entry = cpEntries[i];
167 if (entry == null) {
168 continue;
169 }
170 entry.resolve(cpEntries);
171 }
172 } catch (IllegalArgumentException ioe) {
173 throw new InvalidClassFormatException(ioe);
174 } catch (IndexOutOfBoundsException iobe) {
175 throw new InvalidClassFormatException(iobe);
176 }
177 }
178
179 private CPEntry getConstantPoolEntry(ConstantPoolReader cpr)
180 throws IOException {
181 CPEntry newEntry;
182 byte type = cpr.readByte();
183 switch (type) {
184 case CONSTANT_Utf8:
185 newEntry = new CPUTF8Info(this, cpr.readRawUTF());
186 break;
187
188 case CONSTANT_Integer:
189 newEntry = new CPIntegerInfo(this, cpr.readInt());
190 break;
191
192 case CONSTANT_Float:
193 newEntry = new CPFloatInfo(this, cpr.readFloat());
194 break;
195
196 case CONSTANT_Long:
197 newEntry = new CPLongInfo(this, cpr.readLong());
198 break;
199
200 case CONSTANT_Double:
201 newEntry = new CPDoubleInfo(this, cpr.readDouble());
202 break;
203
204 case CONSTANT_Class: {
205 int nameIndex = cpr.readUnsignedShort();
206 newEntry = new CPClassInfo(this, nameIndex);
207 break;
208 }
209
210 case CONSTANT_String: {
211 int nameIndex = cpr.readUnsignedShort();
212 newEntry = new CPStringInfo(this, nameIndex);
213 break;
214 }
215
216 case CONSTANT_FieldRef: {
217 int classIndex = cpr.readUnsignedShort();
218 int natIndex = cpr.readUnsignedShort();
219 newEntry = new CPFieldInfo(this, classIndex, natIndex);
220 break;
221 }
222
223 case CONSTANT_MethodRef: {
224 int classIndex = cpr.readUnsignedShort();
225 int natIndex = cpr.readUnsignedShort();
226 newEntry = new CPMethodInfo(this, classIndex, natIndex);
227 break;
228 }
229
230 case CONSTANT_InterfaceMethodRef: {
231 int classIndex = cpr.readUnsignedShort();
232 int natIndex = cpr.readUnsignedShort();
233 newEntry = new CPInterfaceMethodInfo(this, classIndex, natIndex);
234 break;
235 }
236
237 case CONSTANT_NameAndType: {
238 int nameIndex = cpr.readUnsignedShort();
239 int descIndex = cpr.readUnsignedShort();
240 newEntry = new CPNameAndTypeInfo(this, nameIndex, descIndex);
241 break;
242 }
243
244 default:
245 throw new IllegalArgumentException (
246 "invalid constant pool type: " + type);
247 }
248
249 return newEntry;
250 }
251 }
252 |
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