| 1 | /* |
| 2 | * Copyright 2005-2006 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.lang.model.util; |
| 27 | |
| 28 | import javax.lang.model.type.*; |
| 29 | |
| 30 | /** |
| 31 | * A skeletal visitor of types with default behavior appropriate for |
| 32 | * the version 6 language level. |
| 33 | * |
| 34 | * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented |
| 35 | * by this class may have methods added to it in the future to |
| 36 | * accommodate new, currently unknown, language structures added to |
| 37 | * future versions of the Java™ programming language. |
| 38 | * Therefore, methods whose names begin with {@code "visit"} may be |
| 39 | * added to this class in the future; to avoid incompatibilities, |
| 40 | * classes which extend this class should not declare any instance |
| 41 | * methods with names beginning with {@code "visit"}. |
| 42 | * |
| 43 | * <p>When such a new visit method is added, the default |
| 44 | * implementation in this class will be to call the {@link |
| 45 | * #visitUnknown visitUnknown} method. A new abstract type visitor |
| 46 | * class will also be introduced to correspond to the new language |
| 47 | * level; this visitor will have different default behavior for the |
| 48 | * visit method in question. When the new visitor is introduced, all |
| 49 | * or portions of this visitor may be deprecated. |
| 50 | * |
| 51 | * @param <R> the return type of this visitor's methods. Use {@link |
| 52 | * Void} for visitors that do not need to return results. |
| 53 | * @param <P> the type of the additional parameter to this visitor's |
| 54 | * methods. Use {@code Void} for visitors that do not need an |
| 55 | * additional parameter. |
| 56 | * |
| 57 | * @author Joseph D. Darcy |
| 58 | * @author Scott Seligman |
| 59 | * @author Peter von der Ahé |
| 60 | * @since 1.6 |
| 61 | */ |
| 62 | public abstract class AbstractTypeVisitor6<R, P> implements TypeVisitor<R, P> { |
| 63 | /** |
| 64 | * Constructor for concrete subclasses to call. |
| 65 | */ |
| 66 | protected AbstractTypeVisitor6() {} |
| 67 | |
| 68 | /** |
| 69 | * Visits any type mirror as if by passing itself to that type |
| 70 | * mirror's {@link TypeMirror#accept accept} method. The |
| 71 | * invocation {@code v.visit(t, p)} is equivalent to {@code |
| 72 | * t.accept(v, p)}. |
| 73 | * |
| 74 | * @param t the type to visit |
| 75 | * @param p a visitor-specified parameter |
| 76 | * @return a visitor-specified result |
| 77 | */ |
| 78 | public final R visit(TypeMirror t, P p) { |
| 79 | return t.accept(this, p); |
| 80 | } |
| 81 | |
| 82 | /** |
| 83 | * Visits any type mirror as if by passing itself to that type |
| 84 | * mirror's {@link TypeMirror#accept accept} method and passing |
| 85 | * {@code null} for the additional parameter. The invocation |
| 86 | * {@code v.visit(t)} is equivalent to {@code t.accept(v, null)}. |
| 87 | * |
| 88 | * @param t the type to visit |
| 89 | * @return a visitor-specified result |
| 90 | */ |
| 91 | public final R visit(TypeMirror t) { |
| 92 | return t.accept(this, null); |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * {@inheritDoc} |
| 97 | * |
| 98 | * <p> The default implementation of this method in {@code |
| 99 | * AbstractTypeVisitor6} will always throw {@code |
| 100 | * UnknownTypeException}. This behavior is not required of a |
| 101 | * subclass. |
| 102 | * |
| 103 | * @param t the type to visit |
| 104 | * @return a visitor-specified result |
| 105 | * @throws UnknownTypeException |
| 106 | * a visitor implementation may optionally throw this exception |
| 107 | */ |
| 108 | public R visitUnknown(TypeMirror t, P p) { |
| 109 | throw new UnknownTypeException(t, p); |
| 110 | } |
| 111 | } |