SimpleAnnotationValueVisitor8.java revision 2571:10fc81ac75b4 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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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.
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25
26package javax.lang.model.util;
27
28import javax.annotation.processing.SupportedSourceVersion;
29import javax.lang.model.SourceVersion;
30import static javax.lang.model.SourceVersion.*;
31
32/**
33 * A simple visitor for annotation values with default behavior
34 * appropriate for the {@link SourceVersion#RELEASE_8 RELEASE_8}
35 * source version.  Visit methods call {@link #defaultAction
36 * defaultAction} passing their arguments to {@code defaultAction}'s
37 * corresponding parameters.
38 *
39 * <p> Methods in this class may be overridden subject to their
40 * general contract.  Note that annotating methods in concrete
41 * subclasses with {@link java.lang.Override @Override} will help
42 * ensure that methods are overridden as intended.
43 *
44 * <p> <b>WARNING:</b> The {@code AnnotationValueVisitor} interface
45 * implemented by this class may have methods added to it in the
46 * future to accommodate new, currently unknown, language structures
47 * added to future versions of the Java&trade; programming language.
48 * Therefore, methods whose names begin with {@code "visit"} may be
49 * added to this class in the future; to avoid incompatibilities,
50 * classes which extend this class should not declare any instance
51 * methods with names beginning with {@code "visit"}.
52 *
53 * <p>When such a new visit method is added, the default
54 * implementation in this class will be to call the {@link
55 * #visitUnknown visitUnknown} method.  A new simple annotation
56 * value visitor class will also be introduced to correspond to the
57 * new language level; this visitor will have different default
58 * behavior for the visit method in question.  When the new visitor is
59 * introduced, all or portions of this visitor may be deprecated.
60 *
61 * <p>Note that adding a default implementation of a new visit method
62 * in a visitor class will occur instead of adding a <em>default
63 * method</em> directly in the visitor interface since a Java SE 8
64 * language feature cannot be used to this version of the API since
65 * this version is required to be runnable on Java SE 7
66 * implementations.  Future versions of the API that are only required
67 * to run on Java SE 8 and later may take advantage of default methods
68 * in this situation.
69 *
70 * @param <R> the return type of this visitor's methods
71 * @param <P> the type of the additional parameter to this visitor's methods.
72 *
73 * @see SimpleAnnotationValueVisitor6
74 * @see SimpleAnnotationValueVisitor7
75 * @see SimpleAnnotationValueVisitor8
76 * @since 1.8
77 */
78@SupportedSourceVersion(RELEASE_8)
79public class SimpleAnnotationValueVisitor8<R, P> extends SimpleAnnotationValueVisitor7<R, P> {
80    /**
81     * Constructor for concrete subclasses; uses {@code null} for the
82     * default value.
83     */
84    protected SimpleAnnotationValueVisitor8() {
85        super(null);
86    }
87
88    /**
89     * Constructor for concrete subclasses; uses the argument for the
90     * default value.
91     *
92     * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
93     */
94    protected SimpleAnnotationValueVisitor8(R defaultValue) {
95        super(defaultValue);
96    }
97}
98