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.element;
027    
028    
029    import java.util.List;
030    import javax.lang.model.type.*;
031    
032    /**
033     * Represents a value of an annotation type element.
034     * A value is of one of the following types:
035     * <ul><li> a wrapper class (such as {@link Integer}) for a primitive type
036     *     <li> {@code String}
037     *     <li> {@code TypeMirror}
038     *     <li> {@code VariableElement} (representing an enum constant)
039     *     <li> {@code AnnotationMirror}
040     *     <li> {@code List<? extends AnnotationValue>}
041     *              (representing the elements, in declared order, if the value is an array)
042     * </ul>
043     *
044     * @author Joseph D. Darcy
045     * @author Scott Seligman
046     * @author Peter von der Ah&eacute;
047     * @since 1.6
048     */
049    public interface AnnotationValue {
050    
051        /**
052         * Returns the value.
053         *
054         * @return the value
055         */
056        Object getValue();
057    
058        /**
059         * Returns a string representation of this value.
060         * This is returned in a form suitable for representing this value
061         * in the source code of an annotation.
062         *
063         * @return a string representation of this value
064         */
065        String toString();
066    
067        /**
068         * Applies a visitor to this value.
069         *
070         * @param <R> the return type of the visitor's methods
071         * @param <P> the type of the additional parameter to the visitor's methods
072         * @param v   the visitor operating on this value
073         * @param p   additional parameter to the visitor
074         * @return a visitor-specified result
075         */
076        <R, P> R accept(AnnotationValueVisitor<R, P> v, P p);
077    }