1 /*
2 * Copyright (c) 2005, 2020, 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 javax.lang.model.util;
27
28 import javax.annotation.processing.SupportedSourceVersion;
29 import javax.lang.model.SourceVersion;
30 import javax.lang.model.type.*;
31 import static javax.lang.model.SourceVersion.*;
32
33 /**
34 * A visitor of types based on their {@linkplain TypeKind kind} with
35 * default behavior appropriate for the {@link SourceVersion#RELEASE_6
36 * RELEASE_6} source version. For {@linkplain
37 * TypeMirror types} <code><i>Xyz</i></code> that may have more than one
38 * kind, the <code>visit<i>Xyz</i></code> methods in this class delegate
39 * to the <code>visit<i>Xyz</i>As<i>Kind</i></code> method corresponding to the
40 * first argument's kind. The <code>visit<i>Xyz</i>As<i>Kind</i></code> methods
41 * call {@link #defaultAction defaultAction}, passing their arguments
42 * to {@code defaultAction}'s corresponding parameters.
43 *
44 * @apiNote
45 * Methods in this class may be overridden subject to their general
46 * contract.
47 *
48 * <p id=note_for_subclasses><strong>WARNING:</strong> The {@code
49 * TypeVisitor} interface implemented by this class may have methods
50 * added to it or the {@link TypeKind TypeKind enum} used in this
51 * class may have constants added to it in the future to accommodate
52 * new, currently unknown, language structures added to future
53 * versions of the Java™ programming language. Therefore,
54 * methods whose names begin with {@code "visit"} may be added to this
55 * class in the future; to avoid incompatibilities, classes and
56 * subclasses which extend this class should not declare any instance
57 * methods with names beginning with {@code "visit"}.</p>
58 *
59 * <p>When such a new visit method is added, the default
60 * implementation in this class will be to directly or indirectly call
61 * the {@link #visitUnknown visitUnknown} method. A new type kind
62 * visitor class will also be introduced to correspond to the new
63 * language level; this visitor will have different default behavior
64 * for the visit method in question. When a new visitor is
65 * introduced, portions of this visitor class may be deprecated,
66 * including its constructors.
67 *
68 * @param <R> the return type of this visitor's methods. Use {@link
69 * Void} for visitors that do not need to return results.
70 * @param <P> the type of the additional parameter to this visitor's
71 * methods. Use {@code Void} for visitors that do not need an
72 * additional parameter.
73 *
74 * @author Joseph D. Darcy
75 * @author Scott Seligman
76 * @author Peter von der Ahé
77 *
78 * @see TypeKindVisitor7
79 * @see TypeKindVisitor8
80 * @see TypeKindVisitor9
81 * @see TypeKindVisitor14
82 * @since 1.6
83 */
84 @SupportedSourceVersion(RELEASE_6)
85 public class TypeKindVisitor6<R, P> extends SimpleTypeVisitor6<R, P> {
86 /**
87 * Constructor for concrete subclasses to call; uses {@code null}
88 * for the default value.
89 * @deprecated Release 6 is obsolete; update to a visitor for a newer
90 * release level.
91 */
92 @Deprecated(since="9")
93 protected TypeKindVisitor6() {
94 super(null);
95 }
96
97
98 /**
99 * Constructor for concrete subclasses to call; uses the argument
100 * for the default value.
101 *
102 * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
103 * @deprecated Release 6 is obsolete; update to a visitor for a newer
104 * release level.
105 */
106 @Deprecated(since="9")
107 protected TypeKindVisitor6(R defaultValue) {
108 super(defaultValue);
109 }
110
111 /**
112 * {@inheritDoc}
113 *
114 * @implSpec This implementation dispatches to the visit method for
115 * the specific {@linkplain TypeKind kind} of primitive type:
116 * {@code BOOLEAN}, {@code BYTE}, etc.
117 *
118 * @param t {@inheritDoc}
119 * @param p {@inheritDoc}
120 * @return the result of the kind-specific visit method
121 */
122 @Override
123 public R visitPrimitive(PrimitiveType t, P p) {
124 TypeKind k = t.getKind();
125 switch (k) {
126 case BOOLEAN:
127 return visitPrimitiveAsBoolean(t, p);
128
129 case BYTE:
130 return visitPrimitiveAsByte(t, p);
131
132 case SHORT:
133 return visitPrimitiveAsShort(t, p);
134
135 case INT:
136 return visitPrimitiveAsInt(t, p);
137
138 case LONG:
139 return visitPrimitiveAsLong(t, p);
140
141 case CHAR:
142 return visitPrimitiveAsChar(t, p);
143
144 case FLOAT:
145 return visitPrimitiveAsFloat(t, p);
146
147 case DOUBLE:
148 return visitPrimitiveAsDouble(t, p);
149
150 default:
151 throw new AssertionError("Bad kind " + k + " for PrimitiveType" + t);
152 }
153 }
154
155 /**
156 * Visits a {@code BOOLEAN} primitive type.
157 *
158 * @implSpec This implementation calls {@code defaultAction}.
159 *
160 * @param t the type to visit
161 * @param p a visitor-specified parameter
162 * @return the result of {@code defaultAction}
163 */
164 public R visitPrimitiveAsBoolean(PrimitiveType t, P p) {
165 return defaultAction(t, p);
166 }
167
168 /**
169 * Visits a {@code BYTE} primitive type.
170 *
171 * @implSpec This implementation calls {@code defaultAction}.
172 *
173 * @param t the type to visit
174 * @param p a visitor-specified parameter
175 * @return the result of {@code defaultAction}
176 */
177 public R visitPrimitiveAsByte(PrimitiveType t, P p) {
178 return defaultAction(t, p);
179 }
180
181 /**
182 * Visits a {@code SHORT} primitive type.
183 *
184 * @implSpec This implementation calls {@code defaultAction}.
185 *
186 * @param t the type to visit
187 * @param p a visitor-specified parameter
188 * @return the result of {@code defaultAction}
189 */
190 public R visitPrimitiveAsShort(PrimitiveType t, P p) {
191 return defaultAction(t, p);
192 }
193
194 /**
195 * Visits an {@code INT} primitive type.
196 *
197 * @implSpec This implementation calls {@code defaultAction}.
198 *
199 * @param t the type to visit
200 * @param p a visitor-specified parameter
201 * @return the result of {@code defaultAction}
202 */
203 public R visitPrimitiveAsInt(PrimitiveType t, P p) {
204 return defaultAction(t, p);
205 }
206
207 /**
208 * Visits a {@code LONG} primitive type.
209 *
210 * @implSpec This implementation calls {@code defaultAction}.
211 *
212 * @param t the type to visit
213 * @param p a visitor-specified parameter
214 * @return the result of {@code defaultAction}
215 */
216 public R visitPrimitiveAsLong(PrimitiveType t, P p) {
217 return defaultAction(t, p);
218 }
219
220 /**
221 * Visits a {@code CHAR} primitive type.
222 *
223 * @implSpec This implementation calls {@code defaultAction}.
224 *
225 * @param t the type to visit
226 * @param p a visitor-specified parameter
227 * @return the result of {@code defaultAction}
228 */
229 public R visitPrimitiveAsChar(PrimitiveType t, P p) {
230 return defaultAction(t, p);
231 }
232
233 /**
234 * Visits a {@code FLOAT} primitive type.
235 *
236 * @implSpec This implementation calls {@code defaultAction}.
237 *
238 * @param t the type to visit
239 * @param p a visitor-specified parameter
240 * @return the result of {@code defaultAction}
241 */
242 public R visitPrimitiveAsFloat(PrimitiveType t, P p) {
243 return defaultAction(t, p);
244 }
245
246 /**
247 * Visits a {@code DOUBLE} primitive type.
248 *
249 * @implSpec This implementation calls {@code defaultAction}.
250 *
251 * @param t the type to visit
252 * @param p a visitor-specified parameter
253 * @return the result of {@code defaultAction}
254 */
255 public R visitPrimitiveAsDouble(PrimitiveType t, P p) {
256 return defaultAction(t, p);
257 }
258
259 /**
260 * {@inheritDoc}
261 *
262 * @implSpec This implementation dispatches to the visit method for
263 * the specific {@linkplain TypeKind kind} of pseudo-type:
264 * {@code VOID}, {@code PACKAGE}, {@code MODULE}, or {@code NONE}.
265 *
266 * @param t {@inheritDoc}
267 * @param p {@inheritDoc}
268 * @return the result of the kind-specific visit method
269 */
270 @Override
271 public R visitNoType(NoType t, P p) {
272 TypeKind k = t.getKind();
273 switch (k) {
274 case VOID:
275 return visitNoTypeAsVoid(t, p);
276
277 case PACKAGE:
278 return visitNoTypeAsPackage(t, p);
279
280 case MODULE:
281 return visitNoTypeAsModule(t, p);
282
283 case NONE:
284 return visitNoTypeAsNone(t, p);
285
286 default:
287 throw new AssertionError("Bad kind " + k + " for NoType" + t);
288 }
289 }
290
291 /**
292 * Visits a {@link TypeKind#VOID VOID} pseudo-type.
293 *
294 * @implSpec This implementation calls {@code defaultAction}.
295 *
296 * @param t the type to visit
297 * @param p a visitor-specified parameter
298 * @return the result of {@code defaultAction}
299 */
300 public R visitNoTypeAsVoid(NoType t, P p) {
301 return defaultAction(t, p);
302 }
303
304 /**
305 * Visits a {@link TypeKind#PACKAGE PACKAGE} pseudo-type.
306 *
307 * @implSpec This implementation calls {@code defaultAction}.
308 *
309 * @param t the type to visit
310 * @param p a visitor-specified parameter
311 * @return the result of {@code defaultAction}
312 */
313 public R visitNoTypeAsPackage(NoType t, P p) {
314 return defaultAction(t, p);
315 }
316
317 /**
318 * Visits a {@link TypeKind#MODULE MODULE} pseudo-type.
319 *
320 * @implSpec This implementation calls {@code visitUnknown}.
321 *
322 * @param t the type to visit
323 * @param p a visitor-specified parameter
324 * @return the result of {@code visitUnknown}
325 *
326 * @since 10
327 */
328 public R visitNoTypeAsModule(NoType t, P p) {
329 return visitUnknown(t, p);
330 }
331
332 /**
333 * Visits a {@link TypeKind#NONE NONE} pseudo-type.
334 *
335 * @implSpec This implementation calls {@code defaultAction}.
336 *
337 * @param t the type to visit
338 * @param p a visitor-specified parameter
339 * @return the result of {@code defaultAction}
340 */
341 public R visitNoTypeAsNone(NoType t, P p) {
342 return defaultAction(t, p);
343 }
344 }