001 /**
002 Licensed to the Apache Software Foundation (ASF) under one or more
003 contributor license agreements. See the NOTICE file distributed with
004 this work for additional information regarding copyright ownership.
005 The ASF licenses this file to You under the Apache License, Version 2.0
006 (the "License"); you may not use this file except in compliance with
007 the License. You may obtain a copy of the License at
008
009 http://www.apache.org/licenses/LICENSE-2.0
010
011 Unless required by applicable law or agreed to in writing, software
012 distributed under the License is distributed on an "AS IS" BASIS,
013 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 See the License for the specific language governing permissions and
015 limitations under the License.
016 */
017 package org.apache.commons.inject.impl;
018
019 import java.util.ArrayList;
020 import java.util.Arrays;
021 import java.util.Collection;
022 import java.util.List;
023
024 import org.apache.commons.inject.api.IBinding;
025 import org.apache.commons.inject.api.IInjector;
026 import org.apache.commons.inject.api.IInjectorBuilder;
027 import org.apache.commons.inject.api.IKey;
028 import org.apache.commons.inject.api.IPoint;
029 import org.apache.commons.inject.api.IProvider;
030 import org.apache.commons.inject.api.Key;
031 import org.apache.commons.inject.api.bind.IAnnotatedBindingBuilder;
032 import org.apache.commons.inject.api.bind.IBinder;
033 import org.apache.commons.inject.api.bind.ILinkedBindingBuilder;
034 import org.apache.commons.inject.api.bind.IModule;
035 import org.apache.commons.inject.api.bind.IBinder.IInjectionListener;
036 import org.apache.commons.inject.api.bind.IBinder.IInjectionParticipator;
037 import org.apache.commons.inject.api.bind.IBinder.IInjectorBuildListener;
038 import org.apache.commons.inject.impl.bind.DefaultBinding;
039 import org.apache.commons.inject.impl.bind.DefaultBindingBuilder;
040
041 public class DefaultInjectorBuilder implements IInjectorBuilder {
042 private final Collection<IModule> modules;
043 private final List<IInjectionListener> injectionListeners = new ArrayList<IInjectionListener>();
044 private final List<IInjectionParticipator> injectionParticipators = new ArrayList<IInjectionParticipator>();
045 private final List<IInjectorBuildListener> injectorBuildListeners = new ArrayList<IInjectorBuildListener>();
046
047 public DefaultInjectorBuilder(Collection<IModule> pModules) {
048 modules = pModules;
049 }
050
051 public DefaultInjectorBuilder() {
052 modules = new ArrayList<IModule>();
053 }
054
055 public IInjector build() {
056 final MutableBindingSet mutableBindings = new MutableBindingSet();
057 configure(mutableBindings);
058 final IKey<IInjector> key = new Key<IInjector>(IInjector.class);
059 final BindingProxy<IInjector> bindingProxy = (BindingProxy<IInjector>) mutableBindings.requireBinding(key, "to create an automatic binding for an injector.");
060 bindingProxy.setResolvedLater(true);
061 final ResolvableBindingSet resolvableBindings = new ResolvableBindingSet(mutableBindings);
062 resolve(resolvableBindings);
063 final ImmutableBindingSet immutableBindings = new ImmutableBindingSet(resolvableBindings);
064 final DefaultInjector injector = new DefaultInjector(immutableBindings);
065 final IProvider<IInjector> provider = new IProvider<IInjector>(){
066 @Override
067 public IInjector get() {
068 return injector;
069 }
070
071 @Override
072 public Class<? extends IInjector> getType() {
073 return injector.getClass();
074 }
075
076 @Override
077 public IInjector get(IInjector pInjector) {
078 return get();
079 }
080 };
081 final IPoint<IInjector> point = new IPoint<IInjector>(){
082 @Override
083 public void injectTo(IInjector pInstance, IInjector pInjector) {
084 // Does nothing.
085 }
086 };
087 bindingProxy.setBinding(new DefaultBinding<IInjector>(provider, point));
088 for (IBinding<?> binding : immutableBindings.getAllBindings()) {
089 if (binding instanceof IInjectorAware) {
090 ((IInjectorAware) binding).init(injector);
091 } else {
092 throw new IllegalStateException("No InjectorAware: " + binding);
093 }
094 }
095 for (IInjectorBuildListener listener : injectorBuildListeners) {
096 listener.created(injector);
097 }
098 return injector;
099 }
100
101 protected void resolve(ResolvableBindingSet pBindings) {
102 pBindings.resolve();
103 }
104
105 protected void configure(final MutableBindingSet mutableBindings) {
106 final List<DefaultBindingBuilder<?>> builders = new ArrayList<DefaultBindingBuilder<?>>();
107 final IBinder binder = newBinder(builders);
108 for (IModule module : modules) {
109 module.configure(binder);
110 }
111 for (DefaultBindingBuilder<?> builder : builders) {
112 builder.build(mutableBindings, injectionListeners, injectionParticipators);
113 }
114 }
115
116 private IBinder newBinder(final List<DefaultBindingBuilder<?>> builders) {
117 return new IBinder(){
118 @Override
119 public <T> IAnnotatedBindingBuilder<T> bind(Class<T> pType) {
120 final DefaultBindingBuilder<T> builder = new DefaultBindingBuilder<T>(pType);
121 builders.add(builder);
122 return builder;
123 }
124
125 @Override
126 public <T> IAnnotatedBindingBuilder<T> bind(Class<T> pType,
127 String pName) {
128 final DefaultBindingBuilder<T> builder = new DefaultBindingBuilder<T>(pType, pName);
129 builders.add(builder);
130 return builder;
131 }
132
133 @Override
134 public <T> ILinkedBindingBuilder<T> bind(IKey<T> pKey) {
135 final DefaultBindingBuilder<T> builder = new DefaultBindingBuilder<T>(pKey);
136 builders.add(builder);
137 return builder;
138 }
139
140 @Override
141 public boolean add(IInjectionParticipator pParticipator) {
142 if (pParticipator == null) {
143 throw new NullPointerException("The participator must not be null.");
144 }
145 return injectionParticipators.add(pParticipator);
146 }
147
148 @Override
149 public boolean add(IInjectionListener pListener) {
150 if (pListener == null) {
151 throw new NullPointerException("The listener must not be null.");
152 }
153 return injectionListeners.add(pListener);
154 }
155
156 @Override
157 public boolean add(IInjectorBuildListener pListener) {
158 if (pListener == null) {
159 throw new NullPointerException("The listener must not be null.");
160 }
161 return injectorBuildListeners.add(pListener);
162 }
163 };
164 }
165
166 @Override
167 public IInjectorBuilder modules(IModule... pModules) {
168 if (pModules == null) {
169 throw new NullPointerException("The module list must not be null.");
170 }
171 modules.addAll(Arrays.asList(pModules));
172 return this;
173 }
174
175 @Override
176 public IInjectorBuilder modules(Collection<IModule> pModules) {
177 if (pModules == null) {
178 throw new NullPointerException("The module list must not be null.");
179 }
180 modules.addAll(pModules);
181 return this;
182 }
183 }