1 /** 2 * This file Copyright (c) 2011 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.lang.reflect.ParameterizedType; 37 import java.lang.reflect.Type; 38 39 import com.google.inject.Binding; 40 import com.google.inject.Injector; 41 import com.google.inject.Key; 42 import info.magnolia.objectfactory.ParameterInfo; 43 import info.magnolia.objectfactory.ParameterResolver; 44 45 /** 46 * Parameter resolver that finds parameters by querying for them in a Guice Injector. Will create javax.inject.Provider 47 * instances that match the parameter's type. 48 * 49 * @version $Id$ 50 */ 51 public class GuiceParameterResolver implements ParameterResolver { 52 53 private final Injector injector; 54 55 public GuiceParameterResolver(Injector injector) { 56 this.injector = injector; 57 } 58 59 public GuiceParameterResolver(GuiceComponentProvider componentProvider) { 60 this.injector = componentProvider.getInjector(); 61 } 62 63 @Override 64 public Object resolveParameter(ParameterInfo parameter) { 65 66 Type genericParameterType = parameter.getGenericParameterType(); 67 Class<?> parameterType = parameter.getParameterType(); 68 69 // We ask for an existing binding so Guice wont create jit bindings for things like Class and String 70 // This means that all parameters need to be explicitly bound 71 72 // If the parameter is javax.inject.Provider<T> we will look for a provider of T instead 73 if (genericParameterType instanceof ParameterizedType) { 74 ParameterizedType parameterizedType = (ParameterizedType) genericParameterType; 75 if (parameterizedType.getRawType() == javax.inject.Provider.class) { 76 Type actualType = parameterizedType.getActualTypeArguments()[0]; 77 Binding<?> existingBinding = injector.getExistingBinding(Key.get(actualType)); 78 return existingBinding != null ? existingBinding.getProvider() : UNRESOLVED; 79 } 80 } 81 82 Key<?> key = Key.get(parameterType); 83 Binding<?> existingBinding = injector.getExistingBinding(key); 84 return existingBinding != null ? existingBinding.getProvider().get() : UNRESOLVED; 85 } 86 }