1 /* 2 * Copyright (c) 2011, 2013, 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.annotation.processing.SupportedSourceVersion; 29 import javax.lang.model.SourceVersion; 30 import static javax.lang.model.SourceVersion.*; 31 32 /** 33 * A simple visitor of types with default behavior appropriate for the 34 * {@link SourceVersion#RELEASE_7 RELEASE_7} source version. 35 * 36 * Visit methods corresponding to {@code RELEASE_8} and earlier 37 * language constructs call {@link #defaultAction defaultAction}, 38 * passing their arguments to {@code defaultAction}'s corresponding 39 * parameters. 40 * 41 * <p> Methods in this class may be overridden subject to their 42 * general contract. Note that annotating methods in concrete 43 * subclasses with {@link java.lang.Override @Override} will help 44 * ensure that methods are overridden as intended. 45 * 46 * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented 47 * by this class may have methods added to it in the future to 48 * accommodate new, currently unknown, language structures added to 49 * future versions of the Java™ programming language. 50 * Therefore, methods whose names begin with {@code "visit"} may be 51 * added to this class in the future; to avoid incompatibilities, 52 * classes which extend this class should not declare any instance 53 * methods with names beginning with {@code "visit"}. 54 * 55 * <p>When such a new visit method is added, the default 56 * implementation in this class will be to call the {@link 57 * #visitUnknown visitUnknown} method. A new simple type visitor 58 * class will also be introduced to correspond to the new language 59 * level; this visitor will have different default behavior for the 60 * visit method in question. When the new visitor is introduced, all 61 * or portions of this visitor may be deprecated. 62 * 63 * <p>Note that adding a default implementation of a new visit method 64 * in a visitor class will occur instead of adding a <em>default 65 * method</em> directly in the visitor interface since a Java SE 8 66 * language feature cannot be used to this version of the API since 67 * this version is required to be runnable on Java SE 7 68 * implementations. Future versions of the API that are only required 69 * to run on Java SE 8 and later may take advantage of default methods 70 * in this situation. 71 * 72 * @param <R> the return type of this visitor's methods. Use {@link 73 * Void} for visitors that do not need to return results. 74 * @param <P> the type of the additional parameter to this visitor's 75 * methods. Use {@code Void} for visitors that do not need an 76 * additional parameter. 77 * 78 * @see SimpleTypeVisitor6 79 * @see SimpleTypeVisitor7 80 * @since 1.8 81 */ 82 @SupportedSourceVersion(RELEASE_8) 83 public class SimpleTypeVisitor8<R, P> extends SimpleTypeVisitor7<R, P> { 84 /** 85 * Constructor for concrete subclasses; uses {@code null} for the 86 * default value. 87 */ 88 protected SimpleTypeVisitor8(){ 89 super(null); 90 } 91 92 /** 93 * Constructor for concrete subclasses; uses the argument for the 94 * default value. 95 * 96 * @param defaultValue the value to assign to {@link #DEFAULT_VALUE} 97 */ 98 protected SimpleTypeVisitor8(R defaultValue){ 99 super(defaultValue); 100 } 101 }