001    /*
002     * Copyright 2005-2006 Sun Microsystems, Inc.  All Rights Reserved.
003     * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004     *
005     * This code is free software; you can redistribute it and/or modify it
006     * under the terms of the GNU General Public License version 2 only, as
007     * published by the Free Software Foundation.  Sun designates this
008     * particular file as subject to the "Classpath" exception as provided
009     * by Sun in the LICENSE file that accompanied this code.
010     *
011     * This code is distributed in the hope that it will be useful, but WITHOUT
012     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013     * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
014     * version 2 for more details (a copy is included in the LICENSE file that
015     * accompanied this code).
016     *
017     * You should have received a copy of the GNU General Public License version
018     * 2 along with this work; if not, write to the Free Software Foundation,
019     * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020     *
021     * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022     * CA 95054 USA or visit www.sun.com if you need additional information or
023     * have any questions.
024     */
025    
026    package javax.lang.model.util;
027    
028    
029    import java.util.List;
030    import javax.lang.model.element.*;
031    
032    import javax.lang.model.type.TypeMirror;
033    import static javax.lang.model.SourceVersion.*;
034    import javax.lang.model.SourceVersion;
035    import javax.annotation.processing.SupportedSourceVersion;
036    
037    /**
038     * A skeletal visitor for annotation values with default behavior
039     * appropriate for the {@link SourceVersion#RELEASE_6 RELEASE_6}
040     * source version.
041     *
042     * <p> <b>WARNING:</b> The {@code AnnotationValueVisitor} interface
043     * implemented by this class may have methods added to it in the
044     * future to accommodate new, currently unknown, language structures
045     * added to future versions of the Java&trade; programming language.
046     * Therefore, methods whose names begin with {@code "visit"} may be
047     * added to this class in the future; to avoid incompatibilities,
048     * classes which extend this class should not declare any instance
049     * methods with names beginning with {@code "visit"}.
050     *
051     * <p>When such a new visit method is added, the default
052     * implementation in this class will be to call the {@link
053     * #visitUnknown visitUnknown} method.  A new abstract annotation
054     * value visitor class will also be introduced to correspond to the
055     * new language level; this visitor will have different default
056     * behavior for the visit method in question.  When the new visitor is
057     * introduced, all or portions of this visitor may be deprecated.
058     *
059     * @param <R> the return type of this visitor's methods
060     * @param <P> the type of the additional parameter to this visitor's methods.
061     *
062     * @author Joseph D. Darcy
063     * @author Scott Seligman
064     * @author Peter von der Ah&eacute;
065     * @since 1.6
066     */
067    @SupportedSourceVersion(RELEASE_6)
068    public abstract class AbstractAnnotationValueVisitor6<R, P>
069        implements AnnotationValueVisitor<R, P> {
070    
071        /**
072         * Constructor for concrete subclasses to call.
073         */
074        protected AbstractAnnotationValueVisitor6() {}
075    
076        /**
077         * Visits an annotation value as if by passing itself to that
078         * value's {@link AnnotationValue#accept accept}.  The invocation
079         * {@code v.visit(av)} is equivalent to {@code av.accept(v, p)}.
080         * @param av {@inheritDoc}
081         * @param p  {@inheritDoc}
082         */
083        public final R visit(AnnotationValue av, P p) {
084            return av.accept(this, p);
085        }
086    
087        /**
088         * Visits an annotation value as if by passing itself to that
089         * value's {@link AnnotationValue#accept accept} method passing
090         * {@code null} for the additional parameter.  The invocation
091         * {@code v.visit(av)} is equivalent to {@code av.accept(v,
092         * null)}.
093         * @param av {@inheritDoc}
094         */
095        public final R visit(AnnotationValue av) {
096            return av.accept(this, null);
097        }
098    
099        /**
100         * {@inheritDoc}
101         *
102         * <p>The default implementation of this method in {@code
103         * AbstractAnnotationValueVisitor6} will always throw {@code
104         * UnknownAnnotationValueException}.  This behavior is not
105         * required of a subclass.
106         *
107         * @param av {@inheritDoc}
108         * @param p  {@inheritDoc}
109         */
110        public R visitUnknown(AnnotationValue av, P p) {
111            throw new UnknownAnnotationValueException(av, p);
112        }
113    }