1 /* 2 * Copyright (c) 2011, 2017, 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 javax.lang.model.type.*; 31 import static javax.lang.model.SourceVersion.*; 32 33 /** 34 * A visitor of types based on their {@linkplain TypeKind kind} with 35 * default behavior appropriate for the {@link SourceVersion#RELEASE_8 36 * RELEASE_8} source version. For {@linkplain 37 * TypeMirror types} <code><i>Xyz</i></code> that may have more than one 38 * kind, the <code>visit<i>Xyz</i></code> methods in this class delegate 39 * to the <code>visit<i>Xyz</i>As<i>Kind</i></code> method corresponding to the 40 * first argument's kind. The <code>visit<i>Xyz</i>As<i>Kind</i></code> methods 41 * call {@link #defaultAction defaultAction}, passing their arguments 42 * to {@code defaultAction}'s corresponding parameters. 43 * 44 * <p> Methods in this class may be overridden subject to their 45 * general contract. Note that annotating methods in concrete 46 * subclasses with {@link java.lang.Override @Override} will help 47 * ensure that methods are overridden as intended. 48 * 49 * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented 50 * by this class may have methods added to it in the future to 51 * accommodate new, currently unknown, language structures added to 52 * future versions of the Java™ programming language. 53 * Therefore, methods whose names begin with {@code "visit"} may be 54 * added to this class in the future; to avoid incompatibilities, 55 * classes which extend this class should not declare any instance 56 * methods with names beginning with {@code "visit"}. 57 * 58 * <p>When such a new visit method is added, the default 59 * implementation in this class will be to call the {@link 60 * #visitUnknown visitUnknown} method. A new type kind visitor class 61 * will also be introduced to correspond to the new language level; 62 * this visitor will have different default behavior for the visit 63 * method in question. When the new visitor is introduced, all or 64 * portions of this visitor may be deprecated. 65 * 66 * @param <R> the return type of this visitor's methods. Use {@link 67 * Void} for visitors that do not need to return results. 68 * @param <P> the type of the additional parameter to this visitor's 69 * methods. Use {@code Void} for visitors that do not need an 70 * additional parameter. 71 * 72 * @see TypeKindVisitor6 73 * @see TypeKindVisitor7 74 * @since 1.8 75 */ 76 @SupportedSourceVersion(RELEASE_8) 77 public class TypeKindVisitor8<R, P> extends TypeKindVisitor7<R, P> { 78 /** 79 * Constructor for concrete subclasses to call; uses {@code null} 80 * for the default value. 81 */ TypeKindVisitor8()82 protected TypeKindVisitor8() { 83 super(null); 84 } 85 86 /** 87 * Constructor for concrete subclasses to call; uses the argument 88 * for the default value. 89 * 90 * @param defaultValue the value to assign to {@link #DEFAULT_VALUE} 91 */ TypeKindVisitor8(R defaultValue)92 protected TypeKindVisitor8(R defaultValue) { 93 super(defaultValue); 94 } 95 96 /** 97 * {@inheritDoc} 98 * 99 * @implSpec This implementation calls {@code defaultAction}. 100 * 101 * @param t {@inheritDoc} 102 * @param p {@inheritDoc} 103 * @return the result of {@code defaultAction} 104 */ 105 @Override visitIntersection(IntersectionType t, P p)106 public R visitIntersection(IntersectionType t, P p) { 107 return defaultAction(t, p); 108 } 109 } 110