TypeKindVisitor6.java revision 3892:444b89786af3
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12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
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25
26package javax.lang.model.util;
27
28import javax.annotation.processing.SupportedSourceVersion;
29import javax.lang.model.SourceVersion;
30import javax.lang.model.type.*;
31import 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&trade; 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 Ah&eacute;
75 *
76 * @see TypeKindVisitor7
77 * @see TypeKindVisitor8
78 * @since 1.6
79 */
80@SupportedSourceVersion(RELEASE_6)
81public 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
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
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}
308