1 /*
2 * Copyright (c) 2005, 2017, 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 * <p> Methods in this class may be overridden subject to their
45 * general contract. Note that annotating methods in concrete
46 * subclasses with {@link java.lang.Override @Override} will help
47 * ensure that methods are overridden as intended.
48 *
49 * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented
50 * by this class may have methods added to it in the future to
51 * accommodate new, currently unknown, language structures added to
52 * future versions of the Java™ programming language.
53 * Therefore, methods whose names begin with {@code "visit"} may be
54 * added to this class in the future; to avoid incompatibilities,
55 * classes which extend this class should not declare any instance
56 * methods with names beginning with {@code "visit"}.
57 *
58 * <p>When such a new visit method is added, the default
59 * implementation in this class will be to call the {@link
60 * #visitUnknown visitUnknown} method. A new type kind visitor class
61 * will also be introduced to correspond to the new language level;
62 * this visitor will have different default behavior for the visit
63 * method in question. When the new visitor is introduced, all or
64 * portions of this visitor may be deprecated.
65 *
66 * @param <R> the return type of this visitor's methods. Use {@link
67 * Void} for visitors that do not need to return results.
68 * @param <P> the type of the additional parameter to this visitor's
69 * methods. Use {@code Void} for visitors that do not need an
70 * additional parameter.
71 *
72 * @author Joseph D. Darcy
73 * @author Scott Seligman
74 * @author Peter von der Ahé
75 *
76 * @see TypeKindVisitor7
77 * @see TypeKindVisitor8
78 * @since 1.6
79 */
80 @SupportedSourceVersion(RELEASE_6)
81 public class TypeKindVisitor6<R, P> extends SimpleTypeVisitor6<R, P> {
82 /**
83 * Constructor for concrete subclasses to call; uses {@code null}
84 * for the default value.
85 * @deprecated Release 6 is obsolete; update to a visitor for a newer
86 * release level.
87 */
88 @Deprecated(since="9")
89 protected TypeKindVisitor6() {
90 super(null);
91 }
92
93
94 /**
95 * Constructor for concrete subclasses to call; uses the argument
96 * for the default value.
97 *
98 * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
99 * @deprecated Release 6 is obsolete; update to a visitor for a newer
100 * release level.
101 */
102 @Deprecated(since="9")
103 protected TypeKindVisitor6(R defaultValue) {
104 super(defaultValue);
105 }
106
107 /**
108 * Visits a primitive type, dispatching to the visit method for
109 * the specific {@linkplain TypeKind kind} of primitive type:
110 * {@code BOOLEAN}, {@code BYTE}, etc.
111 *
112 * @param t {@inheritDoc}
113 * @param p {@inheritDoc}
114 * @return the result of the kind-specific visit method
115 */
116 @Override
117 public R visitPrimitive(PrimitiveType t, P p) {
118 TypeKind k = t.getKind();
119 switch (k) {
120 case BOOLEAN:
121 return visitPrimitiveAsBoolean(t, p);
122
123 case BYTE:
124 return visitPrimitiveAsByte(t, p);
125
126 case SHORT:
127 return visitPrimitiveAsShort(t, p);
128
129 case INT:
130 return visitPrimitiveAsInt(t, p);
131
132 case LONG:
133 return visitPrimitiveAsLong(t, p);
134
135 case CHAR:
136 return visitPrimitiveAsChar(t, p);
137
138 case FLOAT:
139 return visitPrimitiveAsFloat(t, p);
140
141 case DOUBLE:
142 return visitPrimitiveAsDouble(t, p);
143
144 default:
145 throw new AssertionError("Bad kind " + k + " for PrimitiveType" + t);
146 }
147 }
148
149 /**
150 * Visits a {@code BOOLEAN} primitive type by calling
151 * {@code defaultAction}.
152 *
153 * @param t the type to visit
154 * @param p a visitor-specified parameter
155 * @return the result of {@code defaultAction}
156 */
157 public R visitPrimitiveAsBoolean(PrimitiveType t, P p) {
158 return defaultAction(t, p);
159 }
160
161 /**
162 * Visits a {@code BYTE} primitive type by calling
163 * {@code defaultAction}.
164 *
165 * @param t the type to visit
166 * @param p a visitor-specified parameter
167 * @return the result of {@code defaultAction}
168 */
169 public R visitPrimitiveAsByte(PrimitiveType t, P p) {
170 return defaultAction(t, p);
171 }
172
173 /**
174 * Visits a {@code SHORT} primitive type by calling
175 * {@code defaultAction}.
176 *
177 * @param t the type to visit
178 * @param p a visitor-specified parameter
179 * @return the result of {@code defaultAction}
180 */
181 public R visitPrimitiveAsShort(PrimitiveType t, P p) {
182 return defaultAction(t, p);
183 }
184
185 /**
186 * Visits an {@code INT} primitive type by calling
187 * {@code defaultAction}.
188 *
189 * @param t the type to visit
190 * @param p a visitor-specified parameter
191 * @return the result of {@code defaultAction}
192 */
193 public R visitPrimitiveAsInt(PrimitiveType t, P p) {
194 return defaultAction(t, p);
195 }
196
197 /**
198 * Visits a {@code LONG} primitive type by calling
199 * {@code defaultAction}.
200 *
201 * @param t the type to visit
202 * @param p a visitor-specified parameter
203 * @return the result of {@code defaultAction}
204 */
205 public R visitPrimitiveAsLong(PrimitiveType t, P p) {
206 return defaultAction(t, p);
207 }
208
209 /**
210 * Visits a {@code CHAR} primitive type by calling
211 * {@code defaultAction}.
212 *
213 * @param t the type to visit
214 * @param p a visitor-specified parameter
215 * @return the result of {@code defaultAction}
216 */
217 public R visitPrimitiveAsChar(PrimitiveType t, P p) {
218 return defaultAction(t, p);
219 }
220
221 /**
222 * Visits a {@code FLOAT} primitive type by calling
223 * {@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 visitPrimitiveAsFloat(PrimitiveType t, P p) {
230 return defaultAction(t, p);
231 }
232
233 /**
234 * Visits a {@code DOUBLE} primitive type by calling
235 * {@code defaultAction}.
236 *
237 * @param t the type to visit
238 * @param p a visitor-specified parameter
239 * @return the result of {@code defaultAction}
240 */
241 public R visitPrimitiveAsDouble(PrimitiveType t, P p) {
242 return defaultAction(t, p);
243 }
244
245 /**
246 * Visits a {@link NoType} instance, dispatching to the visit method for
247 * the specific {@linkplain TypeKind kind} of pseudo-type:
248 * {@code VOID}, {@code PACKAGE}, or {@code NONE}.
249 *
250 * @param t {@inheritDoc}
251 * @param p {@inheritDoc}
252 * @return the result of the kind-specific visit method
253 */
254 @Override
255 public R visitNoType(NoType t, P p) {
256 TypeKind k = t.getKind();
257 switch (k) {
258 case VOID:
259 return visitNoTypeAsVoid(t, p);
260
261 case PACKAGE:
262 return visitNoTypeAsPackage(t, p);
263
264 case NONE:
265 return visitNoTypeAsNone(t, p);
266
267 default:
268 throw new AssertionError("Bad kind " + k + " for NoType" + t);
269 }
270 }
271
272 /**
273 * Visits a {@link TypeKind#VOID VOID} pseudo-type by calling
274 * {@code defaultAction}.
275 *
276 * @param t the type to visit
277 * @param p a visitor-specified parameter
278 * @return the result of {@code defaultAction}
279 */
280 public R visitNoTypeAsVoid(NoType t, P p) {
281 return defaultAction(t, p);
282 }
283
284 /**
285 * Visits a {@link TypeKind#PACKAGE PACKAGE} pseudo-type by calling
286 * {@code defaultAction}.
287 *
288 * @param t the type to visit
289 * @param p a visitor-specified parameter
290 * @return the result of {@code defaultAction}
291 */
292 public R visitNoTypeAsPackage(NoType t, P p) {
293 return defaultAction(t, p);
294 }
295
296 /**
297 * Visits a {@link TypeKind#NONE NONE} pseudo-type by calling
298 * {@code defaultAction}.
299 *
300 * @param t the type to visit
301 * @param p a visitor-specified parameter
302 * @return the result of {@code defaultAction}
303 */
304 public R visitNoTypeAsNone(NoType t, P p) {
305 return defaultAction(t, p);
306 }
307 }