SimpleElementVisitor9.java revision 3976:65d446c80cdf 
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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
28import javax.annotation.processing.SupportedSourceVersion;
29import javax.lang.model.SourceVersion;
30import javax.lang.model.element.ModuleElement;
31import static javax.lang.model.SourceVersion.*;
32
33/**
34 * A simple visitor of program elements with default behavior
35 * appropriate for the {@link SourceVersion#RELEASE_9 RELEASE_9}
36 * source version.
37 *
38 * Visit methods corresponding to {@code RELEASE_9} and earlier
39 * language constructs call {@link #defaultAction defaultAction},
40 * passing their arguments to {@code defaultAction}'s corresponding
41 * parameters.
42 *
43 * <p> Methods in this class may be overridden subject to their
44 * general contract.  Note that annotating methods in concrete
45 * subclasses with {@link java.lang.Override @Override} will help
46 * ensure that methods are overridden as intended.
47 *
48 * <p> <b>WARNING:</b> The {@code ElementVisitor} interface
49 * implemented by this class may have methods added to it in the
50 * future to accommodate new, currently unknown, language structures
51 * added to future versions of the Java&trade; programming language.
52 * Therefore, methods whose names begin with {@code "visit"} may be
53 * added to this class in the future; to avoid incompatibilities,
54 * classes which extend this class should not declare any instance
55 * methods with names beginning with {@code "visit"}.
56 *
57 * <p>When such a new visit method is added, the default
58 * implementation in this class will be to call the {@link
59 * #visitUnknown visitUnknown} method.  A new simple element visitor
60 * class will also be introduced to correspond to the new language
61 * level; this visitor will have different default behavior for the
62 * visit method in question.  When the new visitor is introduced, all
63 * or portions of this visitor may be deprecated.
64 *
65 * @param <R> the return type of this visitor's methods.  Use {@code Void}
66 *             for visitors that do not need to return results.
67 * @param <P> the type of the additional parameter to this visitor's methods.  Use {@code Void}
68 *              for visitors that do not need an additional parameter.
69 *
70 * @see SimpleElementVisitor6
71 * @see SimpleElementVisitor7
72 * @see SimpleElementVisitor8
73 * @since 9
74 * @spec JPMS
75 */
76@SupportedSourceVersion(RELEASE_9)
77public class SimpleElementVisitor9<R, P> extends SimpleElementVisitor8<R, P> {
78    /**
79     * Constructor for concrete subclasses; uses {@code null} for the
80     * default value.
81     */
82    protected SimpleElementVisitor9(){
83        super(null);
84    }
85
86    /**
87     * Constructor for concrete subclasses; uses the argument for the
88     * default value.
89     *
90     * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
91     */
92    protected SimpleElementVisitor9(R defaultValue){
93        super(defaultValue);
94    }
95
96    /**
97     * Visits a {@code ModuleElement} by calling {@code
98     * defaultAction}.
99     *
100     * @param e the element to visit
101     * @param p a visitor-specified parameter
102     * @return  the result of {@code defaultAction}
103     */
104    @Override
105    public R visitModule(ModuleElement e, P p) {
106        return defaultAction(e, p);
107    }
108}
109