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1 package polyglot.types.reflect;
2
3 import polyglot.types.*;
4 import java.util.*;
5 import java.io.*;
6
7
19 class Field {
20 ClassFile clazz;
21 int modifiers;
22 int name;
23 int type;
24 Attribute[] attrs;
25 ConstantValue constantValue;
26 boolean synthetic;
27
28
33 boolean isString(Type t) {
34 return t.isClass()
35 && t.toClass().isTopLevel()
36 && t.toClass().fullName().equals("java.lang.String");
37 }
38
39 FieldInstance fieldInstance(TypeSystem ts, ClassType ct) {
40 String  name = (String ) clazz.constants[this.name].value();
41 String type = (String ) clazz.constants[this.type].value();
42
43 FieldInstance fi = ts.fieldInstance(ct.position(), ct,
44 ts.flagsForBits(modifiers),
45 clazz.typeForString(ts, type), name);
46
47 Constant c = constantValue();
48
49 if (c != null) {
50 Object o = null;
51
52 try {
53 switch (c.tag()) {
54 case Constant.STRING: o = getString(); break;
55 case Constant.INTEGER: o = new Integer (getInt()); break;
56 case Constant.LONG: o = new Long (getLong()); break;
57 case Constant.FLOAT: o = new Float (getFloat()); break;
58 case Constant.DOUBLE: o = new Double (getDouble()); break;
59 }
60 }
61 catch (SemanticException e) {
62 throw new ClassFormatError ("Unexpected constant pool entry.");
63 }
64
65 if (o != null) {
66 return fi.constantValue(o);
67 }
68 }
69
70 return fi;
71 }
72
73 boolean isSynthetic() {
74 return synthetic;
75 }
76
77 Constant constantValue() {
78 if (this.constantValue != null) {
79 int index = this.constantValue.index;
80 return clazz.constants[index];
81 }
82
83 return null;
84 }
85
86 int getInt() throws SemanticException {
87 Constant c = constantValue();
88
89 if (c != null && c.tag() == Constant.INTEGER) {
90 Integer v = (Integer ) c.value();
91 return v.intValue();
92 }
93
94 throw new SemanticException("Could not find expected constant " +
95 "pool entry with tag INTEGER.");
96 }
97
98 float getFloat() throws SemanticException {
99 Constant c = constantValue();
100
101 if (c != null && c.tag() == Constant.FLOAT) {
102 Float v = (Float ) c.value();
103 return v.floatValue();
104 }
105
106 throw new SemanticException("Could not find expected constant " +
107 "pool entry with tag FLOAT.");
108 }
109
110 double getDouble() throws SemanticException {
111 Constant c = constantValue();
112
113 if (c != null && c.tag() == Constant.DOUBLE) {
114 Double v = (Double ) c.value();
115 return v.doubleValue();
116 }
117
118 throw new SemanticException("Could not find expected constant " +
119 "pool entry with tag DOUBLE.");
120 }
121
122 long getLong() throws SemanticException {
123 Constant c = constantValue();
124
125 if (c != null && c.tag() == Constant.LONG) {
126 Long v = (Long ) c.value();
127 return v.longValue();
128 }
129
130 throw new SemanticException("Could not find expected constant " +
131 "pool entry with tag LONG.");
132 }
133
134 String getString() throws SemanticException {
135 Constant c = constantValue();
136
137 if (c != null && c.tag() == Constant.STRING) {
138 Integer i = (Integer ) c.value();
139 c = clazz.constants[i.intValue()];
140
141 if (c != null && c.tag() == Constant.UTF8) {
142 String v = (String ) c.value();
143 return v;
144 }
145 }
146
147 throw new SemanticException("Could not find expected constant " +
148 "pool entry with tag STRING or UTF8.");
149 }
150
151 String name() {
152 return (String ) clazz.constants[this.name].value();
153 }
154
155
165 Field(DataInputStream in, ClassFile clazz)
166 throws IOException
167 {
168 this.clazz = clazz;
169
170 modifiers = in.readUnsignedShort();
171
172 name = in.readUnsignedShort();
173 type = in.readUnsignedShort();
174
175 int numAttributes = in.readUnsignedShort();
176
177 attrs = new Attribute[numAttributes];
178
179 for (int i = 0; i < numAttributes; i++) {
180 int nameIndex = in.readUnsignedShort();
181 int length = in.readInt();
182
183 Constant name = clazz.constants[nameIndex];
184
185 if (name != null) {
186 if ("ConstantValue".equals(name.value())) {
187 constantValue = new ConstantValue(in, nameIndex, length);
188 attrs[i] = constantValue;
189 }
190 if ("Synthetic".equals(name.value())) {
191 synthetic = true;
192 }
193 }
194
195 if (attrs[i] == null) {
196 long n = in.skip(length);
197 if (n != length) {
198 throw new EOFException();
199 }
200 }
201 }
202 }
203 }
204 |
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