/** | |
* Copyright (C) 2011 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 java.util.List; | |
import java.util.Map; | |
import com.google.inject.Key; | |
import com.google.inject.internal.util.Function; | |
import com.google.inject.internal.util.ImmutableList; | |
import com.google.inject.internal.util.Lists; | |
import com.google.inject.internal.util.MapMaker; | |
import com.google.inject.spi.ProvisionListener; | |
import com.google.inject.spi.ProvisionListenerBinding; | |
/** | |
* {@link ProvisionListenerStackCallback} for each key. | |
* | |
* @author sameb@google.com (Sam Berlin) | |
*/ | |
final class ProvisionListenerCallbackStore { | |
private final ImmutableList<ProvisionListenerBinding> listenerBindings; | |
private final Map<Key<?>, ProvisionListenerStackCallback<?>> cache | |
= new MapMaker().makeComputingMap( | |
new Function<Key<?>, ProvisionListenerStackCallback<?>>() { | |
public ProvisionListenerStackCallback<?> apply(Key<?> key) { | |
return create(key); | |
} | |
}); | |
ProvisionListenerCallbackStore(List<ProvisionListenerBinding> listenerBindings) { | |
this.listenerBindings = ImmutableList.copyOf(listenerBindings); | |
} | |
/** Returns a new {@link ProvisionListenerStackCallback} for the key. | |
*/ | |
@SuppressWarnings("unchecked") // the ProvisionListenerStackCallback type always agrees with the passed type | |
public <T> ProvisionListenerStackCallback<T> get(Key<T> key) { | |
return (ProvisionListenerStackCallback<T>) cache.get(key); | |
} | |
/** | |
* Purges a key from the cache. Use this only if the type is not actually valid for | |
* binding and needs to be purged. (See issue 319 and | |
* ImplicitBindingTest#testCircularJitBindingsLeaveNoResidue and | |
* #testInstancesRequestingProvidersForThemselvesWithChildInjectors for examples of when this is | |
* necessary.) | |
* | |
* Returns true if the type was stored in the cache, false otherwise. | |
*/ | |
boolean remove(Key<?> type) { | |
return cache.remove(type) != null; | |
} | |
/** | |
* Creates a new {@link ProvisionListenerStackCallback} with the correct listeners | |
* for the key. | |
*/ | |
private <T> ProvisionListenerStackCallback<T> create(Key<T> key) { | |
List<ProvisionListener> listeners = null; | |
for (ProvisionListenerBinding binding : listenerBindings) { | |
if (binding.getKeyMatcher().matches(key)) { | |
if (listeners == null) { | |
listeners = Lists.newArrayList(); | |
} | |
listeners.addAll(binding.getListeners()); | |
} | |
} | |
if (listeners == null) { | |
listeners = ImmutableList.of(); | |
} | |
return new ProvisionListenerStackCallback<T>(key, listeners); | |
} | |
} |