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.lang.model.type.*;
29 
30 /**
31  * A skeletal visitor of types with default behavior appropriate for
32  * the {@link javax.lang.model.SourceVersion#RELEASE_8 RELEASE_8}
33  * source version.
34  *
35  * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented
36  * by this class may have methods added to it in the future to
37  * accommodate new, currently unknown, language structures added to
38  * future versions of the Java&trade; programming language.
39  * Therefore, methods whose names begin with {@code "visit"} may be
40  * added to this class in the future; to avoid incompatibilities,
41  * classes which extend this class should not declare any instance
42  * methods with names beginning with {@code "visit"}.
43  *
44  * <p>When such a new visit method is added, the default
45  * implementation in this class will be to call the {@link
46  * #visitUnknown visitUnknown} method.  A new abstract type visitor
47  * class will also be introduced to correspond to the new language
48  * level; this visitor will have different default behavior for the
49  * visit method in question.  When the new visitor is introduced, all
50  * or portions of this visitor may be deprecated.
51  *
52  * <p>Note that adding a default implementation of a new visit method
53  * in a visitor class will occur instead of adding a <em>default
54  * method</em> directly in the visitor interface since a Java SE 8
55  * language feature cannot be used to this version of the API since
56  * this version is required to be runnable on Java SE 7
57  * implementations.  Future versions of the API that are only required
58  * to run on Java SE 8 and later may take advantage of default methods
59  * in this situation.
60  *
61  * @param <R> the return type of this visitor's methods.  Use {@link
62  *            Void} for visitors that do not need to return results.
63  * @param <P> the type of the additional parameter to this visitor's
64  *            methods.  Use {@code Void} for visitors that do not need an
65  *            additional parameter.
66  *
67  * @see AbstractTypeVisitor6
68  * @see AbstractTypeVisitor7
69  * @since 1.8
70  */
71 public abstract class AbstractTypeVisitor8<R, P> extends AbstractTypeVisitor7<R, P> {
72     /**
73      * Constructor for concrete subclasses to call.
74      */
AbstractTypeVisitor8()75     protected AbstractTypeVisitor8() {
76         super();
77     }
78 
79     /**
80      * Visits an {@code IntersectionType} in a manner defined by a subclass.
81      *
82      * @param t  {@inheritDoc}
83      * @param p  {@inheritDoc}
84      * @return the result of the visit as defined by a subclass
85      */
visitIntersection(IntersectionType t, P p)86     public abstract R visitIntersection(IntersectionType t, P p);
87 }
88