1 /*
2 * Grapht, an open source dependency injector.
3 * Copyright 2014-2015 various contributors (see CONTRIBUTORS.txt)
4 * Copyright 2010-2014 Regents of the University of Minnesota
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU Lesser General Public License as
8 * published by the Free Software Foundation; either version 2.1 of the
9 * License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
14 * details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program; if not, write to the Free Software Foundation, Inc., 51
18 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20 package org.grouplens.grapht.reflect;
21
22 import javax.inject.Provider;
23
24 /**
25 * An interface for visiting {@link Satisfaction}s.
26 *
27 * @param <T> The type returned from this satisfaction's values.
28 * @author <a href="http://grouplens.org">GroupLens Research</a>
29 * @since 0.5
30 * @see Satisfaction
31 */
32 public interface SatisfactionVisitor<T> {
33 /**
34 * Called when visiting a null satisfaction.
35 *
36 * @return The return value.
37 */
38 T visitNull();
39
40 /**
41 * Called when visiting a satisfaction that will instantiate a class.
42 *
43 * @param clazz The implementation class.
44 * @return The return value.
45 */
46 T visitClass(Class<?> clazz);
47
48 /**
49 * Called when visiting a satisfaction that will return a pre-configured instance.
50 *
51 * @param instance The instance that will be returned. The visitor should not modify it
52 * in any way.
53 * @return The return value.
54 */
55 T visitInstance(Object instance);
56
57 /**
58 * Called when visiting a satisfaction that will instantiate and invoke a provider class.
59 *
60 * @param pclass The provider class.
61 * @return The return value.
62 */
63 T visitProviderClass(Class<? extends Provider<?>> pclass);
64
65 /**
66 * Called when visiting a satisfaction that will invoke a pre-instantiated provider.
67 *
68 * @param provider The provider instance. The visitor should not modify it in any way.
69 * @return The return value.
70 */
71 T visitProviderInstance(Provider<?> provider);
72 }