1 /**
2 * This file Copyright (c) 2011-2018 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
39 import javax.inject.Provider;
40
41 /**
42 * Parameter resolver which looks for suitable parameters in a set of candidates. Cannot handle null values since its
43 * unable to match them to a type. Will create javax.inject.Provider instances that match the parameter's type.
44 */
45 public class CandidateParameterResolver implements ParameterResolver {
46
47 private final Object[] candidates;
48
49 public CandidateParameterResolver(Object[] candidates) {
50 this.candidates = candidates;
51 }
52
53 @Override
54 public Object resolveParameter(ParameterInfo parameter) {
55
56 Type genericParameterType = parameter.getGenericParameterType();
57 Class<?> parameterType = parameter.getParameterType();
58
59 // If the parameter is javax.inject.Provider<T> we will look for T instead and return a provider for it
60 if (genericParameterType instanceof ParameterizedType) {
61 ParameterizedType parameterizedType = (ParameterizedType) genericParameterType;
62 if (parameterizedType.getRawType() == javax.inject.Provider.class) {
63 Class<?> actualType = (Class<?>) parameterizedType.getActualTypeArguments()[0];
64 for (final Object extraCandidate : candidates) {
65 if (actualType.isAssignableFrom(extraCandidate.getClass())) {
66 return new Provider() {
67 @Override
68 public Object get() {
69 return extraCandidate;
70 }
71 };
72 }
73 }
74 return UNRESOLVED;
75 }
76 }
77 for (Object extraCandidate : candidates) {
78 if (parameterType.isInstance(extraCandidate)) {
79 return extraCandidate;
80 }
81 }
82 return UNRESOLVED;
83 }
84 }