| /** |
| * Copyright (C) 2006 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.inject.internal; |
| |
| import com.google.inject.Key; |
| import com.google.inject.internal.util.ImmutableList; |
| import com.google.inject.internal.util.Maps; |
| import com.google.inject.spi.Dependency; |
| import com.google.inject.spi.DependencyAndSource; |
| |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * Internal context. Used to coordinate injections and support circular |
| * dependencies. |
| * |
| * @author crazybob@google.com (Bob Lee) |
| */ |
| final class InternalContext { |
| |
| private Map<Object, ConstructionContext<?>> constructionContexts = Maps.newHashMap(); |
| /** Keeps track of the type that is currently being requested for injection. */ |
| private Dependency dependency; |
| /** Keeps track of the hierarchy of types needed during injection. */ |
| private LinkedList<DependencyAndSource> state = new LinkedList<DependencyAndSource>(); |
| |
| @SuppressWarnings("unchecked") |
| public <T> ConstructionContext<T> getConstructionContext(Object key) { |
| ConstructionContext<T> constructionContext |
| = (ConstructionContext<T>) constructionContexts.get(key); |
| if (constructionContext == null) { |
| constructionContext = new ConstructionContext<T>(); |
| constructionContexts.put(key, constructionContext); |
| } |
| return constructionContext; |
| } |
| |
| public Dependency getDependency() { |
| return dependency; |
| } |
| |
| /** Sets the new current dependency & adds it to the state. */ |
| public Dependency pushDependency(Dependency dependency, Object source) { |
| Dependency previous = this.dependency; |
| this.dependency = dependency; |
| state.addLast(new DependencyAndSource(dependency, source)); |
| return previous; |
| } |
| |
| /** Pops the current state & sets the new dependency. */ |
| public void popStateAndSetDependency(Dependency newDependency) { |
| popState(); |
| this.dependency = newDependency; |
| } |
| |
| /** Adds to the state without setting the dependency. */ |
| public void pushState(Key<?> key, Object source) { |
| state.addLast(new DependencyAndSource(key == null ? null : Dependency.get(key), source)); |
| } |
| |
| /** Pops from the state without setting a dependency. */ |
| public void popState() { |
| state.removeLast(); |
| } |
| |
| /** Returns the current dependency chain (all the state). */ |
| public List<DependencyAndSource> getDependencyChain() { |
| return ImmutableList.copyOf(state); |
| } |
| } |