|
1 package com.sun.org.apache.bcel.internal.generic;
2
3
56
57 import com.sun.org.apache.bcel.internal.Constants;
58 import com.sun.org.apache.bcel.internal.classfile.*;
59 import java.util.ArrayList  ;
60 import java.util.Iterator ;
61
62
71 public class FieldGen extends FieldGenOrMethodGen {
72 private Object value = null;
73
74
84 public FieldGen(int access_flags, Type type, String name, ConstantPoolGen cp) {
85 setAccessFlags(access_flags);
86 setType(type);
87 setName(name);
88 setConstantPool(cp);
89 }
90
91
97 public FieldGen(Field field, ConstantPoolGen cp) {
98 this(field.getAccessFlags(), Type.getType(field.getSignature()), field.getName(), cp);
99
100 Attribute[] attrs = field.getAttributes();
101
102 for(int i=0; i < attrs.length; i++) {
103 if(attrs[i] instanceof ConstantValue)
104 setValue(((ConstantValue)attrs[i]).getConstantValueIndex());
105 else
106 addAttribute(attrs[i]);
107 }
108 }
109
110 private void setValue(int index) {
111 ConstantPool cp = this.cp.getConstantPool();
112 Constant c = cp.getConstant(index);
113 value = ((ConstantObject)c).getConstantValue(cp);
114 }
115
116
120 public void setInitValue(String str) {
121 checkType(new ObjectType("java.lang.String"));
122
123 if(str != null)
124 value = str;
125 }
126
127 public void setInitValue(long l) {
128 checkType(Type.LONG);
129
130 if(l != 0L)
131 value = new Long (l);
132 }
133
134 public void setInitValue(int i) {
135 checkType(Type.INT);
136
137 if(i != 0)
138 value = new Integer (i);
139 }
140
141 public void setInitValue(short s) {
142 checkType(Type.SHORT);
143
144 if(s != 0)
145 value = new Integer (s);
146 }
147
148 public void setInitValue(char c) {
149 checkType(Type.CHAR);
150
151 if(c != 0)
152 value = new Integer (c);
153 }
154
155 public void setInitValue(byte b) {
156 checkType(Type.BYTE);
157
158 if(b != 0)
159 value = new Integer (b);
160 }
161
162 public void setInitValue(boolean b) {
163 checkType(Type.BOOLEAN);
164
165 if(b)
166 value = new Integer (1);
167 }
168
169 public void setInitValue(float f) {
170 checkType(Type.FLOAT);
171
172 if(f != 0.0)
173 value = new Float (f);
174 }
175
176 public void setInitValue(double d) {
177 checkType(Type.DOUBLE);
178
179 if(d != 0.0)
180 value = new Double (d);
181 }
182
183
185 public void cancelInitValue() {
186 value = null;
187 }
188
189 private void checkType(Type atype) {
190 if(type == null)
191 throw new ClassGenException("You haven't defined the type of the field yet");
192
193 if(!isFinal())
194 throw new ClassGenException("Only final fields may have an initial value!");
195
196 if(!type.equals(atype))
197 throw new ClassGenException("Types are not compatible: " + type + " vs. " + atype);
198 }
199
200
203 public Field getField() {
204 String signature = getSignature();
205 int name_index = cp.addUtf8(name);
206 int signature_index = cp.addUtf8(signature);
207
208 if(value != null) {
209 checkType(type);
210 int index = addConstant();
211 addAttribute(new ConstantValue(cp.addUtf8("ConstantValue"),
212 2, index, cp.getConstantPool()));
213 }
214
215 return new Field(access_flags, name_index, signature_index, getAttributes(),
216 cp.getConstantPool());
217 }
218
219 private int addConstant() {
220 switch(type.getType()) {
221 case Constants.T_INT: case Constants.T_CHAR: case Constants.T_BYTE:
222 case Constants.T_BOOLEAN: case Constants.T_SHORT:
223 return cp.addInteger(((Integer )value).intValue());
224
225 case Constants.T_FLOAT:
226 return cp.addFloat(((Float )value).floatValue());
227
228 case Constants.T_DOUBLE:
229 return cp.addDouble(((Double )value).doubleValue());
230
231 case Constants.T_LONG:
232 return cp.addLong(((Long )value).longValue());
233
234 case Constants.T_REFERENCE:
235 return cp.addString(((String )value));
236
237 default:
238 throw new RuntimeException ("Oops: Unhandled : " + type.getType());
239 }
240 }
241
242 public String getSignature() { return type.getSignature(); }
243
244 private ArrayList observers;
245
246
248 public void addObserver(FieldObserver o) {
249 if(observers == null)
250 observers = new ArrayList ();
251
252 observers.add(o);
253 }
254
255
257 public void removeObserver(FieldObserver o) {
258 if(observers != null)
259 observers.remove(o);
260 }
261
262
266 public void update() {
267 if(observers != null)
268 for(Iterator e = observers.iterator(); e.hasNext(); )
269 ((FieldObserver)e.next()).notify(this);
270 }
271
272 public String getInitValue() {
273 if(value != null) {
274 return value.toString();
275 } else
276 return null;
277 }
278
279
285 public final String toString() {
286 String name, signature, access;
288 access = Utility.accessToString(access_flags);
289 access = access.equals("")? "" : (access + " ");
290 signature = type.toString();
291 name = getName();
292
293 StringBuffer buf = new StringBuffer (access + signature + " " + name);
294 String value = getInitValue();
295
296 if(value != null)
297 buf.append(" = " + value);
298
299 return buf.toString();
300 }
301
302
304 public FieldGen copy(ConstantPoolGen cp) {
305 FieldGen fg = (FieldGen)clone();
306
307 fg.setConstantPool(cp);
308 return fg;
309 }
310 }
311 |
Popular Tags |
Java API By Example, From Geeks To Geeks.