1 /* 2 * Copyright (c) 2010, 2011 Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 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. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package javax.lang.model.util; 27 28 import javax.lang.model.element.*; 29 import static javax.lang.model.element.ElementKind.*; 30 import javax.annotation.processing.SupportedSourceVersion; 31 import static javax.lang.model.SourceVersion.*; 32 import javax.lang.model.SourceVersion; 33 34 /** 35 * A visitor of program elements based on their {@linkplain 36 * ElementKind kind} with default behavior appropriate for the {@link 37 * SourceVersion#RELEASE_7 RELEASE_7} source version. For {@linkplain 38 * Element elements} <tt><i>XYZ</i></tt> that may have more than one 39 * kind, the <tt>visit<i>XYZ</i></tt> methods in this class delegate 40 * to the <tt>visit<i>XYZKind</i></tt> method corresponding to the 41 * first argument's kind. The <tt>visit<i>XYZKind</i></tt> methods 42 * call {@link #defaultAction defaultAction}, passing their arguments 43 * to {@code defaultAction}'s corresponding parameters. 44 * 45 * <p> Methods in this class may be overridden subject to their 46 * general contract. Note that annotating methods in concrete 47 * subclasses with {@link java.lang.Override @Override} will help 48 * ensure that methods are overridden as intended. 49 * 50 * <p> <b>WARNING:</b> The {@code ElementVisitor} interface 51 * implemented by this class may have methods added to it or the 52 * {@code ElementKind} {@code enum} used in this case may have 53 * constants added to it in the future to accommodate new, currently 54 * unknown, language structures added to future versions of the 55 * Java™ programming language. Therefore, methods whose names 56 * begin with {@code "visit"} may be added to this class in the 57 * future; to avoid incompatibilities, classes which extend this class 58 * should not declare any instance methods with names beginning with 59 * {@code "visit"}. 60 * 61 * <p>When such a new visit method is added, the default 62 * implementation in this class will be to call the {@link 63 * #visitUnknown visitUnknown} method. A new abstract element kind 64 * visitor class will also be introduced to correspond to the new 65 * language level; this visitor will have different default behavior 66 * for the visit method in question. When the new visitor is 67 * introduced, all or portions of this visitor may be deprecated. 68 * 69 * @param <R> the return type of this visitor's methods. Use {@link 70 * Void} for visitors that do not need to return results. 71 * @param <P> the type of the additional parameter to this visitor's 72 * methods. Use {@code Void} for visitors that do not need an 73 * additional parameter. 74 * 75 * @see ElementKindVisitor6 76 * @since 1.7 77 */ 78 @SupportedSourceVersion(RELEASE_7) 79 public class ElementKindVisitor7<R, P> extends ElementKindVisitor6<R, P> { 80 /** 81 * Constructor for concrete subclasses; uses {@code null} for the 82 * default value. 83 */ 84 protected ElementKindVisitor7() { 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 ElementKindVisitor7(R defaultValue) { 95 super(defaultValue); 96 } 97 98 /** 99 * Visits a {@code RESOURCE_VARIABLE} variable element by calling 100 * {@code defaultAction}. 101 * 102 * @param e {@inheritDoc} 103 * @param p {@inheritDoc} 104 * @return the result of {@code defaultAction} 105 */ 106 @Override 107 public R visitVariableAsResourceVariable(VariableElement e, P p) { 108 return defaultAction(e, p); 109 } 110 }