1 /**
2 * This file Copyright (c) 2011-2015 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.objectfactory;
35
36 import java.lang.reflect.ParameterizedType;
37 import java.lang.reflect.Type;
38 import javax.inject.Provider;
39
40 /**
41 * Parameter resolver which looks for suitable parameters in a set of candidates. Cannot handle null values since its
42 * unable to match them to a type. Will create javax.inject.Provider instances that match the parameter's type.
43 */
44 public class CandidateParameterResolver implements ParameterResolver {
45
46 private final Object[] candidates;
47
48 public CandidateParameterResolver(Object[] candidates) {
49 this.candidates = candidates;
50 }
51
52 @Override
53 public Object resolveParameter(ParameterInfo parameter) {
54
55 Type genericParameterType = parameter.getGenericParameterType();
56 Class<?> parameterType = parameter.getParameterType();
57
58 // If the parameter is javax.inject.Provider<T> we will look for T instead and return a provider for it
59 if (genericParameterType instanceof ParameterizedType) {
60 ParameterizedType parameterizedType = (ParameterizedType) genericParameterType;
61 if (parameterizedType.getRawType() == javax.inject.Provider.class) {
62 Class<?> actualType = (Class<?>) parameterizedType.getActualTypeArguments()[0];
63 for (final Object extraCandidate : candidates) {
64 if (actualType.isAssignableFrom(extraCandidate.getClass())) {
65 return new Provider() {
66 @Override
67 public Object get() {
68 return extraCandidate;
69 }
70 };
71 }
72 }
73 return UNRESOLVED;
74 }
75 }
76 for (Object extraCandidate : candidates) {
77 if (parameterType.isAssignableFrom(extraCandidate.getClass())) {
78 return extraCandidate;
79 }
80 }
81 return UNRESOLVED;
82 }
83 }