1 /**
2 * This file Copyright (c) 2011-2013 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.guice;
35
36 import java.util.List;
37
38 import com.google.inject.Binding;
39 import com.google.inject.Injector;
40 import com.google.inject.Key;
41 import com.google.inject.TypeLiteral;
42 import com.google.inject.internal.Annotations;
43 import com.google.inject.internal.Errors;
44 import com.google.inject.internal.ErrorsException;
45
46 import info.magnolia.objectfactory.MgnlInstantiationException;
47 import info.magnolia.objectfactory.ParameterInfo;
48 import info.magnolia.objectfactory.ParameterResolver;
49
50 /**
51 * Parameter resolver that finds parameters by querying for them in a Guice Injector. Will create javax.inject.Provider
52 * instances that match the parameter's type.
53 *
54 * @version $Id$
55 */
56 public class GuiceParameterResolver implements ParameterResolver {
57
58 private final Injector injector;
59
60 public GuiceParameterResolver(Injector injector) {
61 this.injector = injector;
62 }
63
64 public GuiceParameterResolver(GuiceComponentProvider componentProvider) {
65 this.injector = componentProvider.getInjector();
66 }
67
68 @Override
69 public Object resolveParameter(ParameterInfo parameter) {
70
71 // We ask for an existing binding so Guice wont create jit bindings for things like Class and String
72 // This means that all parameters need to be explicitly bound
73
74 Key<?> key = getKey(parameter);
75 Binding<?> existingBinding = injector.getExistingBinding(key);
76 return existingBinding != null ? existingBinding.getProvider().get() : UNRESOLVED;
77 }
78
79 private Key<?> getKey(ParameterInfo parameter) {
80 try {
81
82 // Get TypeLiteral for this parameter
83 TypeLiteral<?> declaringType = TypeLiteral.get(parameter.getDeclaringClass());
84 List<TypeLiteral<?>> parameterTypes = declaringType.getParameterTypes(parameter.getConstructor());
85 TypeLiteral<?> parameterType = parameterTypes.get(parameter.getParameterIndex());
86
87 // Create Key object for this parameter
88 Errors errors = new Errors(parameter.getConstructor());
89 return Annotations.getKey(
90 parameterType,
91 parameter.getConstructor(),
92 parameter.getParameterAnnotations(),
93 errors);
94
95 } catch (ErrorsException e) {
96 throw new MgnlInstantiationException(e.getMessage(), e);
97 }
98 }
99 }