AbstractAnnotationValueVisitor6.java revision 3508:2cdcc9283e47 
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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).
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25
26package javax.lang.model.util;
27
28
29import javax.lang.model.element.*;
30
31import static javax.lang.model.SourceVersion.*;
32import javax.lang.model.SourceVersion;
33import javax.annotation.processing.SupportedSourceVersion;
34
35/**
36 * A skeletal visitor for annotation values with default behavior
37 * appropriate for the {@link SourceVersion#RELEASE_6 RELEASE_6}
38 * source version.
39 *
40 * <p> <b>WARNING:</b> The {@code AnnotationValueVisitor} interface
41 * implemented by this class may have methods added to it in the
42 * future to accommodate new, currently unknown, language structures
43 * added to future versions of the Java&trade; programming language.
44 * Therefore, methods whose names begin with {@code "visit"} may be
45 * added to this class in the future; to avoid incompatibilities,
46 * classes which extend this class should not declare any instance
47 * methods with names beginning with {@code "visit"}.
48 *
49 * <p>When such a new visit method is added, the default
50 * implementation in this class will be to call the {@link
51 * #visitUnknown visitUnknown} method.  A new abstract annotation
52 * value visitor class will also be introduced to correspond to the
53 * new language level; this visitor will have different default
54 * behavior for the visit method in question.  When the new visitor is
55 * introduced, all or portions of this visitor may be deprecated.
56 *
57 * <p>Note that adding a default implementation of a new visit method
58 * in a visitor class will occur instead of adding a <em>default
59 * method</em> directly in the visitor interface since a Java SE 8
60 * language feature cannot be used to this version of the API since
61 * this version is required to be runnable on Java SE 7
62 * implementations.  Future versions of the API that are only required
63 * to run on Java SE 8 and later may take advantage of default methods
64 * in this situation.
65 *
66 * @param <R> the return type of this visitor's methods
67 * @param <P> the type of the additional parameter to this visitor's methods.
68 *
69 * @author Joseph D. Darcy
70 * @author Scott Seligman
71 * @author Peter von der Ah&eacute;
72 *
73 * @see AbstractAnnotationValueVisitor7
74 * @see AbstractAnnotationValueVisitor8
75 * @see AbstractAnnotationValueVisitor9
76 * @since 1.6
77 * @deprecated Release 6 is obsolete; update to a visitor for a newer
78 * release level.
79 */
80@Deprecated
81@SupportedSourceVersion(RELEASE_6)
82public abstract class AbstractAnnotationValueVisitor6<R, P>
83    implements AnnotationValueVisitor<R, P> {
84
85    /**
86     * Constructor for concrete subclasses to call.
87     */
88    protected AbstractAnnotationValueVisitor6() {}
89
90    /**
91     * Visits an annotation value as if by passing itself to that
92     * value's {@link AnnotationValue#accept accept}.  The invocation
93     * {@code v.visit(av)} is equivalent to {@code av.accept(v, p)}.
94     * @param av {@inheritDoc}
95     * @param p  {@inheritDoc}
96     */
97    public final R visit(AnnotationValue av, P p) {
98        return av.accept(this, p);
99    }
100
101    /**
102     * Visits an annotation value as if by passing itself to that
103     * value's {@link AnnotationValue#accept accept} method passing
104     * {@code null} for the additional parameter.  The invocation
105     * {@code v.visit(av)} is equivalent to {@code av.accept(v,
106     * null)}.
107     * @param av {@inheritDoc}
108     */
109    public final R visit(AnnotationValue av) {
110        return av.accept(this, null);
111    }
112
113    /**
114     * {@inheritDoc}
115     *
116     * @implSpec The default implementation of this method in {@code
117     * AbstractAnnotationValueVisitor6} will always throw {@code
118     * UnknownAnnotationValueException}.  This behavior is not
119     * required of a subclass.
120     *
121     * @param av {@inheritDoc}
122     * @param p  {@inheritDoc}
123     */
124    @Override
125    public R visitUnknown(AnnotationValue av, P p) {
126        throw new UnknownAnnotationValueException(av, p);
127    }
128}
129