limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 1 | /** |
| 2 | * Copyright (C) 2008 Google Inc. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.google.inject.internal; |
| 18 | |
| 19 | import com.google.inject.Scope; |
| 20 | import com.google.inject.Scopes; |
| 21 | import com.google.inject.Singleton; |
| 22 | import com.google.inject.Stage; |
limpbizkit | 5ae41eb | 2009-06-06 17:51:27 +0000 | [diff] [blame^] | 23 | import com.google.inject.Key; |
| 24 | import com.google.inject.Provider; |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 25 | import com.google.inject.binder.ScopedBindingBuilder; |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 26 | import com.google.inject.spi.BindingScopingVisitor; |
| 27 | import java.lang.annotation.Annotation; |
| 28 | |
| 29 | /** |
| 30 | * References a scope, either directly (as a scope instance), or indirectly (as a scope annotation). |
| 31 | * The scope's eager or laziness is also exposed. |
| 32 | * |
| 33 | * @author jessewilson@google.com (Jesse Wilson) |
| 34 | */ |
| 35 | public abstract class Scoping { |
| 36 | |
| 37 | /** |
| 38 | * No scoping annotation has been applied. Note that this is different from {@code |
| 39 | * in(Scopes.NO_SCOPE)}, where the 'NO_SCOPE' has been explicitly applied. |
| 40 | */ |
| 41 | public static final Scoping UNSCOPED = new Scoping() { |
| 42 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 43 | return visitor.visitNoScoping(); |
| 44 | } |
| 45 | |
| 46 | @Override public Scope getScopeInstance() { |
| 47 | return Scopes.NO_SCOPE; |
| 48 | } |
| 49 | |
| 50 | @Override public String toString() { |
| 51 | return Scopes.NO_SCOPE.toString(); |
| 52 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 53 | |
| 54 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 55 | // do nothing |
| 56 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 57 | }; |
| 58 | |
| 59 | public static final Scoping SINGLETON_ANNOTATION = new Scoping() { |
| 60 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 61 | return visitor.visitScopeAnnotation(Singleton.class); |
| 62 | } |
| 63 | |
| 64 | @Override public Class<? extends Annotation> getScopeAnnotation() { |
| 65 | return Singleton.class; |
| 66 | } |
| 67 | |
| 68 | @Override public String toString() { |
| 69 | return Singleton.class.getName(); |
| 70 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 71 | |
| 72 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 73 | scopedBindingBuilder.in(Singleton.class); |
| 74 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 75 | }; |
| 76 | |
| 77 | public static final Scoping SINGLETON_INSTANCE = new Scoping() { |
| 78 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 79 | return visitor.visitScope(Scopes.SINGLETON); |
| 80 | } |
| 81 | |
| 82 | @Override public Scope getScopeInstance() { |
| 83 | return Scopes.SINGLETON; |
| 84 | } |
| 85 | |
| 86 | @Override public String toString() { |
| 87 | return Scopes.SINGLETON.toString(); |
| 88 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 89 | |
| 90 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 91 | scopedBindingBuilder.in(Scopes.SINGLETON); |
| 92 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 93 | }; |
| 94 | |
| 95 | public static final Scoping EAGER_SINGLETON = new Scoping() { |
| 96 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 97 | return visitor.visitEagerSingleton(); |
| 98 | } |
| 99 | |
| 100 | @Override public Scope getScopeInstance() { |
| 101 | return Scopes.SINGLETON; |
| 102 | } |
| 103 | |
| 104 | @Override public String toString() { |
| 105 | return "eager singleton"; |
| 106 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 107 | |
| 108 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 109 | scopedBindingBuilder.asEagerSingleton(); |
| 110 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 111 | }; |
| 112 | |
| 113 | public static Scoping forAnnotation(final Class<? extends Annotation> scopingAnnotation) { |
| 114 | if (scopingAnnotation == Singleton.class) { |
| 115 | return SINGLETON_ANNOTATION; |
| 116 | } |
| 117 | |
| 118 | return new Scoping() { |
| 119 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 120 | return visitor.visitScopeAnnotation(scopingAnnotation); |
| 121 | } |
| 122 | |
| 123 | @Override public Class<? extends Annotation> getScopeAnnotation() { |
| 124 | return scopingAnnotation; |
| 125 | } |
| 126 | |
| 127 | @Override public String toString() { |
| 128 | return scopingAnnotation.getName(); |
| 129 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 130 | |
| 131 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 132 | scopedBindingBuilder.in(scopingAnnotation); |
| 133 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 134 | }; |
| 135 | } |
| 136 | |
| 137 | public static Scoping forInstance(final Scope scope) { |
| 138 | if (scope == Scopes.SINGLETON) { |
| 139 | return SINGLETON_INSTANCE; |
| 140 | } |
| 141 | |
| 142 | return new Scoping() { |
| 143 | public <V> V acceptVisitor(BindingScopingVisitor<V> visitor) { |
| 144 | return visitor.visitScope(scope); |
| 145 | } |
| 146 | |
| 147 | @Override public Scope getScopeInstance() { |
| 148 | return scope; |
| 149 | } |
| 150 | |
| 151 | @Override public String toString() { |
| 152 | return scope.toString(); |
| 153 | } |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 154 | |
| 155 | public void applyTo(ScopedBindingBuilder scopedBindingBuilder) { |
| 156 | scopedBindingBuilder.in(scope); |
| 157 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 158 | }; |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * Returns true if this scope was explicitly applied. If no scope was explicitly applied then the |
| 163 | * scoping annotation will be used. |
| 164 | */ |
| 165 | public boolean isExplicitlyScoped() { |
| 166 | return this != UNSCOPED; |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | * Returns true if this is the default scope. In this case a new instance will be provided for |
| 171 | * each injection. |
| 172 | */ |
| 173 | public boolean isNoScope() { |
| 174 | return getScopeInstance() == Scopes.NO_SCOPE; |
| 175 | } |
| 176 | |
| 177 | /** |
| 178 | * Returns true if this scope is a singleton that should be loaded eagerly in {@code stage}. |
| 179 | */ |
| 180 | public boolean isEagerSingleton(Stage stage) { |
| 181 | if (this == EAGER_SINGLETON) { |
| 182 | return true; |
| 183 | } |
| 184 | |
| 185 | if (stage == Stage.PRODUCTION) { |
| 186 | return this == SINGLETON_ANNOTATION || this == SINGLETON_INSTANCE; |
| 187 | } |
| 188 | |
| 189 | return false; |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Returns the scope instance, or {@code null} if that isn't known for this instance. |
| 194 | */ |
| 195 | public Scope getScopeInstance() { |
| 196 | return null; |
| 197 | } |
| 198 | |
| 199 | /** |
| 200 | * Returns the scope annotation, or {@code null} if that isn't known for this instance. |
| 201 | */ |
| 202 | public Class<? extends Annotation> getScopeAnnotation() { |
| 203 | return null; |
| 204 | } |
| 205 | |
| 206 | public abstract <V> V acceptVisitor(BindingScopingVisitor<V> visitor); |
| 207 | |
limpbizkit | 03b81a6 | 2009-03-18 05:34:39 +0000 | [diff] [blame] | 208 | public abstract void applyTo(ScopedBindingBuilder scopedBindingBuilder); |
| 209 | |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 210 | private Scoping() {} |
limpbizkit | 5ae41eb | 2009-06-06 17:51:27 +0000 | [diff] [blame^] | 211 | |
| 212 | /** Scopes an internal factory. */ |
| 213 | static <T> InternalFactory<? extends T> scope(Key<T> key, InjectorImpl injector, |
| 214 | InternalFactory<? extends T> creator, Scoping scoping) { |
| 215 | |
| 216 | if (scoping.isNoScope()) { |
| 217 | return creator; |
| 218 | } |
| 219 | |
| 220 | Scope scope = scoping.getScopeInstance(); |
| 221 | |
| 222 | Provider<T> scoped |
| 223 | = scope.scope(key, new ProviderToInternalFactoryAdapter<T>(injector, creator)); |
| 224 | return new InternalFactoryToProviderAdapter<T>( |
| 225 | Initializables.<Provider<? extends T>>of(scoped)); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Replaces annotation scopes with instance scopes using the Injector's annotation-to-instance |
| 230 | * map. If the scope annotation has no corresponding instance, an error will be added and unscoped |
| 231 | * will be retuned. |
| 232 | */ |
| 233 | static Scoping makeInjectable(Scoping scoping, InjectorImpl injector, Errors errors) { |
| 234 | Class<? extends Annotation> scopeAnnotation = scoping.getScopeAnnotation(); |
| 235 | if (scopeAnnotation == null) { |
| 236 | return scoping; |
| 237 | } |
| 238 | |
| 239 | Scope scope = injector.state.getScope(scopeAnnotation); |
| 240 | if (scope != null) { |
| 241 | return forInstance(scope); |
| 242 | } |
| 243 | |
| 244 | errors.scopeNotFound(scopeAnnotation); |
| 245 | return UNSCOPED; |
| 246 | } |
limpbizkit | 76c24b1 | 2008-12-25 04:32:41 +0000 | [diff] [blame] | 247 | } |