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1   /*
2    * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package com.sun.codemodel.internal;
27  
28  import java.lang.annotation.Annotation;
29  import java.util.ArrayList;
30  import java.util.List;
31  import java.util.Set;
32  import java.util.TreeSet;
33  import java.util.Collections;
34  import java.util.Collection;
35  
36  import com.sun.codemodel.internal.util.ClassNameComparator;
37  
38  /**
39   * Java method.
40   */
41  public class JMethod extends JGenerifiableImpl implements JDeclaration, JAnnotatable, JDocCommentable {
42  
43          /**
44           * Modifiers for this method
45           */
46          private JMods mods;
47  
48          /**
49           * Return type for this method
50           */
51          private JType type = null;
52  
53          /**
54           * Name of this method
55           */
56          private String name = null;
57  
58          /**
59           * List of parameters for this method's declaration
60           */
61          private final List<JVar> params = new ArrayList<JVar>();
62  
63          /**
64           * Set of exceptions that this method may throw.
65       * A set instance lazily created.
66           */
67          private Set<JClass> _throws;
68  
69          /**
70           * JBlock of statements that makes up the body this method
71           */
72          private JBlock body = null;
73  
74          private JDefinedClass outer;
75  
76          /**
77           * javadoc comments for this JMethod
78           */
79          private JDocComment jdoc = null;
80  
81          /**
82           * Variable parameter for this method's varargs declaration
83           * introduced in J2SE 1.5
84           */
85          private JVar varParam = null;
86  
87      /**
88       * Annotations on this variable. Lazily created.
89       */
90      private List<JAnnotationUse> annotations = null;
91  
92  
93          private boolean isConstructor() {
94                  return type == null;
95          }
96  
97      /** To set the default value for the
98       *  annotation member
99       */
100     private JExpression defaultValue = null;
101 
102 
103         /**
104          * JMethod constructor
105          *
106          * @param mods
107          *        Modifiers for this method's declaration
108          *
109          * @param type
110          *        Return type for the method
111          *
112          * @param name
113          *        Name of this method
114          */
115         JMethod(JDefinedClass outer, int mods, JType type, String name) {
116                 this.mods = JMods.forMethod(mods);
117                 this.type = type;
118                 this.name = name;
119                 this.outer = outer;
120         }
121 
122         /**
123          * Constructor constructor
124          *
125          * @param mods
126          *        Modifiers for this constructor's declaration
127          *
128          * @param _class
129          *        JClass containing this constructor
130          */
131         JMethod(int mods, JDefinedClass _class) {
132                 this.mods = JMods.forMethod(mods);
133                 this.type = null;
134                 this.name = _class.name();
135                 this.outer = _class;
136         }
137 
138     private Set<JClass> getThrows() {
139         if(_throws==null)
140             _throws = new TreeSet<JClass>(ClassNameComparator.theInstance);
141         return _throws;
142     }
143 
144         /**
145          * Add an exception to the list of exceptions that this
146          * method may throw.
147          *
148          * @param exception
149          *        Name of an exception that this method may throw
150          */
151         public JMethod _throws(JClass exception) {
152         getThrows().add(exception);
153                 return this;
154         }
155 
156         public JMethod _throws(Class<? extends Throwable> exception) {
157                 return _throws(outer.owner().ref(exception));
158         }
159 
160         /**
161          * Returns the list of variable of this method.
162          *
163          * @return List of parameters of this method. This list is not modifiable.
164          */
165         public List<JVar> params() {
166                 return Collections.<JVar>unmodifiableList(params);
167         }
168 
169         /**
170          * Add the specified variable to the list of parameters
171          * for this method signature.
172          *
173          * @param type
174          *        JType of the parameter being added
175          *
176          * @param name
177          *        Name of the parameter being added
178          *
179          * @return New parameter variable
180          */
181         public JVar param(int mods, JType type, String name) {
182                 JVar v = new JVar(JMods.forVar(mods), type, name, null);
183                 params.add(v);
184                 return v;
185         }
186 
187         public JVar param(JType type, String name) {
188                 return param(JMod.NONE, type, name);
189         }
190 
191         public JVar param(int mods, Class<?> type, String name) {
192                 return param(mods, outer.owner()._ref(type), name);
193         }
194 
195         public JVar param(Class<?> type, String name) {
196                 return param(outer.owner()._ref(type), name);
197         }
198 
199         /**
200          * @see #varParam(JType, String)
201          */
202         public JVar varParam(Class<?> type, String name) {
203         return varParam(outer.owner()._ref(type),name);
204     }
205 
206     /**
207      * Add the specified variable argument to the list of parameters
208      * for this method signature.
209      *
210      * @param type
211      *      Type of the parameter being added.
212      *
213      * @param name
214      *        Name of the parameter being added
215      *
216      * @return the variable parameter
217      *
218      * @throws IllegalStateException
219      *      If this method is called twice.
220      *      varargs in J2SE 1.5 can appear only once in the
221      *      method signature.
222      */
223     public JVar varParam(JType type, String name) {
224                 if (!hasVarArgs()) {
225 
226             varParam =
227                                 new JVar(
228                                         JMods.forVar(JMod.NONE),
229                                         type.array(),
230                                         name,
231                                         null);
232                         return varParam;
233                 } else {
234                         throw new IllegalStateException(
235                                 "Cannot have two varargs in a method,\n"
236                                         + "Check if varParam method of JMethod is"
237                                         + " invoked more than once");
238 
239                 }
240 
241         }
242 
243     /**
244      * Adds an annotation to this variable.
245      * @param clazz
246      *          The annotation class to annotate the field with
247      */
248     public JAnnotationUse annotate(JClass clazz){
249         if(annotations==null)
250            annotations = new ArrayList<JAnnotationUse>();
251         JAnnotationUse a = new JAnnotationUse(clazz);
252         annotations.add(a);
253         return a;
254     }
255 
256     /**
257      * Adds an annotation to this variable.
258      *
259      * @param clazz
260      *          The annotation class to annotate the field with
261      */
262     public JAnnotationUse annotate(Class <? extends Annotation> clazz){
263         return annotate(owner().ref(clazz));
264     }
265 
266     public <W extends JAnnotationWriter> W annotate2(Class<W> clazz) {
267         return TypedAnnotationWriter.create(clazz,this);
268     }
269 
270     public Collection<JAnnotationUse> annotations() {
271         if (annotations == null)
272             annotations = new ArrayList<JAnnotationUse>();
273         return Collections.unmodifiableList(annotations);
274     }
275 
276     /**
277          * Check if there are any varargs declared
278          * for this method signature.
279          */
280         public boolean hasVarArgs() {
281                 return this.varParam!=null;
282         }
283 
284         public String name() {
285                 return name;
286         }
287 
288     /**
289      * Changes the name of the method.
290      */
291     public void name(String n) {
292         this.name = n;
293     }
294 
295     /**
296          * Returns the return type.
297          */
298         public JType type() {
299                 return type;
300         }
301 
302     /**
303      * Overrides the return type.
304      */
305     public void type(JType t) {
306         this.type = t;
307     }
308 
309     /**
310          * Returns all the parameter types in an array.
311          * @return
312          *      If there's no parameter, an empty array will be returned.
313          */
314         public JType[] listParamTypes() {
315                 JType[] r = new JType[params.size()];
316                 for (int i = 0; i < r.length; i++)
317                         r[i] = params.get(i).type();
318                 return r;
319         }
320 
321         /**
322          * Returns  the varags parameter type.
323          * @return
324          * If there's no vararg parameter type, null will be returned.
325          */
326         public JType listVarParamType() {
327                 if (varParam != null)
328                         return varParam.type();
329                 else
330                         return null;
331         }
332 
333         /**
334          * Returns all the parameters in an array.
335          * @return
336          *      If there's no parameter, an empty array will be returned.
337          */
338         public JVar[] listParams() {
339                 return params.toArray(new JVar[params.size()]);
340         }
341 
342         /**
343          * Returns the variable parameter
344          * @return
345          *      If there's no parameter, null will be returned.
346          */
347         public JVar listVarParam() {
348                 return varParam;
349         }
350 
351         /**
352          * Returns true if the method has the specified signature.
353          */
354         public boolean hasSignature(JType[] argTypes) {
355                 JVar[] p = listParams();
356                 if (p.length != argTypes.length)
357                         return false;
358 
359                 for (int i = 0; i < p.length; i++)
360                         if (!p[i].type().equals(argTypes[i]))
361                                 return false;
362 
363                 return true;
364         }
365 
366         /**
367          * Get the block that makes up body of this method
368          *
369          * @return Body of method
370          */
371         public JBlock body() {
372                 if (body == null)
373                         body = new JBlock();
374                 return body;
375         }
376 
377     /**
378      * Specify the default value for this annotation member
379      * @param value
380      *           Default value for the annotation member
381      *
382      */
383     public void declareDefaultValue(JExpression value){
384         this.defaultValue = value;
385     }
386 
387         /**
388          * Creates, if necessary, and returns the class javadoc for this
389          * JDefinedClass
390          *
391          * @return JDocComment containing javadocs for this class
392          */
393         public JDocComment javadoc() {
394                 if (jdoc == null)
395                         jdoc = new JDocComment(owner());
396                 return jdoc;
397         }
398 
399         public void declare(JFormatter f) {
400                 if (jdoc != null)
401                         f.g(jdoc);
402 
403         if (annotations != null){
404             for (JAnnotationUse a : annotations)
405                 f.g(a).nl();
406         }
407 
408         f.g(mods);
409 
410         // declare the generics parameters
411                 super.declare(f);
412 
413                 if (!isConstructor())
414                         f.g(type);
415                 f.id(name).p('(').i();
416         // when parameters are printed in new lines, we want them to be indented.
417         // there's a good chance no newlines happen, too, but just in case it does.
418                 boolean first = true;
419         for (JVar var : params) {
420             if (!first)
421                 f.p(',');
422             if(var.isAnnotated())
423                 f.nl();
424             f.b(var);
425             first = false;
426         }
427                 if (hasVarArgs()) {
428                         if (!first)
429                                 f.p(',');
430                         f.g(varParam.type().elementType());
431                         f.p("... ");
432                         f.id(varParam.name());
433                 }
434 
435                 f.o().p(')');
436                 if (_throws!=null && !_throws.isEmpty()) {
437                         f.nl().i().p("throws").g(_throws).nl().o();
438                 }
439 
440         if (defaultValue != null) {
441             f.p("default ");
442             f.g(defaultValue);
443         }
444                 if (body != null) {
445                         f.s(body);
446                 } else if (
447                         !outer.isInterface() && !outer.isAnnotationTypeDeclaration() && !mods.isAbstract() && !mods.isNative()) {
448                         // Print an empty body for non-native, non-abstract methods
449                         f.s(new JBlock());
450                 } else {
451                         f.p(';').nl();
452                 }
453         }
454 
455     /**
456      * @return
457      *      the current modifiers of this method.
458      *      Always return non-null valid object.
459      */
460     public JMods mods() {
461         return mods;
462     }
463 
464     /**
465      * @deprecated use {@link #mods()}
466      */
467     public JMods getMods() {
468                 return mods;
469         }
470 
471         protected JCodeModel owner() {
472                 return outer.owner();
473         }
474 }