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16
17 package org.cojen.classfile;
18
19 import java.io.Serializable  ;
20 import java.io.Externalizable ;
21 import java.io.ObjectOutput ;
22 import java.io.ObjectInput ;
23 import java.io.IOException ;
24 import java.io.ObjectStreamException ;
25 import java.lang.reflect.Method ;
26 import java.util.List ;
27 import java.util.ArrayList ;
28 import org.cojen.util.WeakCanonicalSet;
29
30
37 public class MethodDesc extends Descriptor implements Serializable {
38 private static final TypeDesc[] EMPTY_PARAMS = new TypeDesc[0];
39
40 private final static WeakCanonicalSet mInstances = TypeDesc.cInstances;
42
43 static MethodDesc intern(MethodDesc desc) {
44 return (MethodDesc)mInstances.put(desc);
45 }
46
47
52 public static MethodDesc forArguments(TypeDesc ret, TypeDesc[] params) {
53 if (ret == null) {
54 ret = TypeDesc.VOID;
55 }
56 if (params == null || params.length == 0) {
57 params = EMPTY_PARAMS;
58 }
59 return intern(new MethodDesc(ret, params));
60 }
61
62
66 public static MethodDesc forDescriptor(String desc)
67 throws IllegalArgumentException
68 {
69 try {
70 int cursor = 0;
71 char c;
72
73 if ((c = desc.charAt(cursor++)) != '(') {
74 throw invalidDescriptor(desc);
75 }
76
77 StringBuffer buf = new StringBuffer ();
78 List list = new ArrayList ();
79
80 while ((c = desc.charAt(cursor++)) != ')') {
81 switch (c) {
82 case 'V':
83 case 'I':
84 case 'C':
85 case 'Z':
86 case 'D':
87 case 'F':
88 case 'J':
89 case 'B':
90 case 'S':
91 buf.append(c);
92 break;
93 case '[':
94 buf.append(c);
95 continue;
96 case 'L':
97 while (true) {
98 buf.append(c);
99 if (c == ';') {
100 break;
101 }
102 c = desc.charAt(cursor++);
103 }
104 break;
105 default:
106 throw invalidDescriptor(desc);
107 }
108
109 list.add(TypeDesc.forDescriptor(buf.toString()));
110 buf.setLength(0);
111 }
112
113 TypeDesc ret = TypeDesc.forDescriptor(desc.substring(cursor));
114
115 TypeDesc[] tds = new TypeDesc[list.size()];
116 tds = (TypeDesc[])list.toArray(tds);
117
118 return intern(new MethodDesc(desc, ret, tds));
119 } catch (NullPointerException e) {
120 throw invalidDescriptor(desc);
121 } catch (IndexOutOfBoundsException e) {
122 throw invalidDescriptor(desc);
123 }
124 }
125
126 public static MethodDesc forMethod(Method method) {
127 Class [] paramClasses = method.getParameterTypes();
128 TypeDesc[] paramTypes;
129 if (paramClasses == null || paramClasses.length == 0) {
130 paramTypes = EMPTY_PARAMS;
131 } else {
132 paramTypes = new TypeDesc[paramClasses.length];
133 for (int i=paramClasses.length; --i>=0; ) {
134 paramTypes[i] = TypeDesc.forClass(paramClasses[i]);
135 }
136 }
137 return forArguments(TypeDesc.forClass(method.getReturnType()), paramTypes);
138 }
139
140 private static IllegalArgumentException invalidDescriptor(String desc) {
141 return new IllegalArgumentException ("Invalid descriptor: " + desc);
142 }
143
144 private transient final String mDescriptor;
145 private transient final TypeDesc mRetType;
146 private transient final TypeDesc[] mParams;
147
148 private MethodDesc(TypeDesc ret, TypeDesc[] params) {
149 mDescriptor = generateDescriptor(ret, params);
150 mRetType = ret;
151 mParams = params;
152 }
153
154 private MethodDesc(String desc, TypeDesc ret, TypeDesc[] params) {
155 mDescriptor = desc;
156 mRetType = ret;
157 mParams = params;
158 }
159
160
163 public String getDescriptor() {
164 return mDescriptor;
165 }
166
167
170
172
175 public TypeDesc getReturnType() {
176 return mRetType;
177 }
178
179 public int getParameterCount() {
180 return mParams.length;
181 }
182
183 public TypeDesc[] getParameterTypes() {
184 TypeDesc[] params = mParams;
185 return (params != EMPTY_PARAMS) ? (TypeDesc[])params.clone() : params;
186 }
187
188
193 public String toMethodSignature(String name) {
194 return toMethodSignature(name, false);
195 }
196
197
204 public String toMethodSignature(String name, boolean varargs) {
205 StringBuffer buf = new StringBuffer ();
206 buf.append(mRetType.getFullName());
207 buf.append(' ');
208 buf.append(name);
209 buf.append('(');
210
211 TypeDesc[] params = mParams;
212 for (int i=0; i<params.length; i++) {
213 if (i > 0) {
214 buf.append(", ");
215 }
216 TypeDesc param = params[i];
217 if (varargs && param.isArray() && i == (params.length - 1)) {
218 buf.append(param.getComponentType().getFullName());
219 buf.append("...");
220 } else {
221 buf.append(param.getFullName());
222 }
223 }
224
225 return buf.append(')').toString();
226 }
227
228 public String toString() {
229 return mDescriptor;
231 }
232
233 public int hashCode() {
234 return mDescriptor.hashCode();
235 }
236
237 public boolean equals(Object other) {
238 if (this == other) {
239 return true;
240 }
241 if (other instanceof MethodDesc) {
242 return ((MethodDesc)other).mDescriptor.equals(mDescriptor);
243 }
244 return false;
245 }
246
247 Object writeReplace() throws ObjectStreamException {
248 return new External(mDescriptor);
249 }
250
251 private static String generateDescriptor(TypeDesc ret, TypeDesc[] params) {
252 int length = ret.getDescriptor().length() + 2;
253 int paramsLength = params.length;
254 for (int i=paramsLength; --i >=0; ) {
255 length += params[i].getDescriptor().length();
256 }
257 char[] buf = new char[length];
258 buf[0] = '(';
259 int index = 1;
260 String paramDesc;
261 for (int i=0; i<paramsLength; i++) {
262 paramDesc = params[i].getDescriptor();
263 int paramDescLength = paramDesc.length();
264 paramDesc.getChars(0, paramDescLength, buf, index);
265 index += paramDescLength;
266 }
267 buf[index++] = ')';
268 paramDesc = ret.getDescriptor();
269 paramDesc.getChars(0, paramDesc.length(), buf, index);
270 return new String (buf);
271 }
272
273 private static class External implements Externalizable {
274 private String mDescriptor;
275
276 public External() {
277 }
278
279 public External(String desc) {
280 mDescriptor = desc;
281 }
282
283 public void writeExternal(ObjectOutput out) throws IOException {
284 out.writeUTF(mDescriptor);
285 }
286
287 public void readExternal(ObjectInput in) throws IOException {
288 mDescriptor = in.readUTF();
289 }
290
291 public Object readResolve() throws ObjectStreamException {
292 return forDescriptor(mDescriptor);
293 }
294 }
295 }
296 |
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