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1
19
20 package jode.bytecode;
21 import java.io.DataInputStream  ;
22 import java.io.IOException ;
23
24
29 public class ConstantPool {
30 public final static int CLASS = 7;
31 public final static int FIELDREF = 9;
32 public final static int METHODREF = 10;
33 public final static int INTERFACEMETHODREF = 11;
34 public final static int STRING = 8;
35 public final static int INTEGER = 3;
36 public final static int FLOAT = 4;
37 public final static int LONG = 5;
38 public final static int DOUBLE = 6;
39 public final static int NAMEANDTYPE = 12;
40 public final static int UTF8 = 1;
41
42 int count;
43 int[] tags;
44 int[] indices1, indices2;
45
46 Object [] constants;
47
48 public ConstantPool () {
49 }
50
51 public void read(DataInputStream stream)
52 throws IOException {
53 count = stream.readUnsignedShort();
54 tags = new int[count];
55 indices1 = new int[count];
56 indices2 = new int[count];
57 constants = new Object [count];
58
59 for (int i=1; i< count; i++) {
60 int tag = stream.readUnsignedByte();
61 tags[i] = tag;
62 switch (tag) {
63 case CLASS:
64 indices1[i] = stream.readUnsignedShort();
65 break;
66 case FIELDREF:
67 case METHODREF:
68 case INTERFACEMETHODREF:
69 indices1[i] = stream.readUnsignedShort();
70 indices2[i] = stream.readUnsignedShort();
71 break;
72 case STRING:
73 indices1[i] = stream.readUnsignedShort();
74 break;
75 case INTEGER:
76 constants[i] = new Integer (stream.readInt());
77 break;
78 case FLOAT:
79 constants[i] = new Float (stream.readFloat());
80 break;
81 case LONG:
82 constants[i] = new Long (stream.readLong());
83 tags[++i] = -LONG;
84 break;
85 case DOUBLE:
86 constants[i] = new Double (stream.readDouble());
87 tags[++i] = -DOUBLE;
88 break;
89 case NAMEANDTYPE:
90 indices1[i] = stream.readUnsignedShort();
91 indices2[i] = stream.readUnsignedShort();
92 break;
93 case UTF8:
94 constants[i] = stream.readUTF().intern();
95 break;
96 default:
97 throw new ClassFormatException("unknown constant tag");
98 }
99 }
100 }
101
102 public int getTag(int i) throws ClassFormatException {
103 if (i == 0)
104 throw new ClassFormatException("null tag");
105 return tags[i];
106 }
107
108 public String getUTF8(int i) throws ClassFormatException {
109 if (i == 0)
110 return null;
111 if (tags[i] != UTF8)
112 throw new ClassFormatException("Tag mismatch");
113 return (String )constants[i];
114 }
115
116 public Reference getRef(int i) throws ClassFormatException {
117 if (i == 0)
118 return null;
119 if (tags[i] != FIELDREF
120 && tags[i] != METHODREF && tags[i] != INTERFACEMETHODREF)
121 throw new ClassFormatException("Tag mismatch");
122 if (constants[i] == null) {
123 int classIndex = indices1[i];
124 int nameTypeIndex = indices2[i];
125 if (tags[nameTypeIndex] != NAMEANDTYPE)
126 throw new ClassFormatException("Tag mismatch");
127 String type = getUTF8(indices2[nameTypeIndex]);
128 try {
129 if (tags[i] == FIELDREF)
130 TypeSignature.checkTypeSig(type);
131 else
132 TypeSignature.checkMethodTypeSig(type);
133 } catch (IllegalArgumentException ex) {
134 throw new ClassFormatException(ex.getMessage());
135 }
136 String clName = getClassType(classIndex);
137 constants[i] = Reference.getReference
138 (clName, getUTF8(indices1[nameTypeIndex]), type);
139 }
140 return (Reference) constants[i];
141 }
142
143 public Object getConstant(int i) throws ClassFormatException {
144 if (i == 0)
145 throw new ClassFormatException("null constant");
146 switch (tags[i]) {
147 case ConstantPool.INTEGER:
148 case ConstantPool.FLOAT:
149 case ConstantPool.LONG:
150 case ConstantPool.DOUBLE:
151 return constants[i];
152 case ConstantPool.STRING:
153 return getUTF8(indices1[i]);
154 }
155 throw new ClassFormatException("Tag mismatch: "+tags[i]);
156 }
157
158 public String getClassType(int i) throws ClassFormatException {
159 if (i == 0)
160 return null;
161 if (tags[i] != CLASS)
162 throw new ClassFormatException("Tag mismatch");
163 String clName = getUTF8(indices1[i]);
164 if (clName.charAt(0) != '[') {
165 clName = ("L"+clName+';').intern();
166 }
167 try {
168 TypeSignature.checkTypeSig(clName);
169 } catch (IllegalArgumentException ex) {
170 throw new ClassFormatException(ex.getMessage());
171 }
172
173 return clName;
174 }
175
176 public String getClassName(int i) throws ClassFormatException {
177 if (i == 0)
178 return null;
179 if (tags[i] != CLASS)
180 throw new ClassFormatException("Tag mismatch");
181 String clName = getUTF8(indices1[i]);
182 try {
183 TypeSignature.checkTypeSig("L"+clName+";");
184 } catch (IllegalArgumentException ex) {
185 throw new ClassFormatException(ex.getMessage());
186 }
187 return clName.replace('/','.').intern();
188 }
189
190 public String toString(int i) {
191 switch (tags[i]) {
192 case CLASS:
193 return "Class "+toString(indices1[i]);
194 case STRING:
195 return "String \""+toString(indices1[i])+"\"";
196 case INTEGER:
197 return "Int "+constants[i].toString();
198 case FLOAT:
199 return "Float "+constants[i].toString();
200 case LONG:
201 return "Long "+constants[i].toString();
202 case DOUBLE:
203 return "Double "+constants[i].toString();
204 case UTF8:
205 return constants[i].toString();
206 case FIELDREF:
207 return "Fieldref: "+toString(indices1[i])+"; "
208 + toString(indices2[i]);
209 case METHODREF:
210 return "Methodref: "+toString(indices1[i])+"; "
211 + toString(indices2[i]);
212 case INTERFACEMETHODREF:
213 return "Interfaceref: "+toString(indices1[i])+"; "
214 + toString(indices2[i]);
215 case NAMEANDTYPE:
216 return "Name "+toString(indices1[i])
217 +"; Type "+toString(indices2[i]);
218 default:
219 return "unknown tag: "+tags[i];
220 }
221 }
222
223 public int size() {
224 return count;
225 }
226
227 public String toString() {
228 StringBuffer result = new StringBuffer ("[ null");
229 for (int i=1; i< count; i++) {
230 result.append(", ").append(i).append(" = ").append(toString(i));
231 }
232 result.append(" ]");
233 return result.toString();
234 }
235 }
236 |
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