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/* * Copyright (C) 2007 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 static com.google.common.base.Preconditions.checkState; import static com.google.inject.internal.Annotations.findScopeAnnotation; import static com.google.inject.internal.RehashableKeys.Keys.needsRehashing; import static com.google.inject.internal.RehashableKeys.Keys.rehash; import com.google.common.base.Objects; import com.google.common.collect.ImmutableSet; import com.google.inject.Binder; import com.google.inject.ConfigurationException; import com.google.inject.Inject; import com.google.inject.Key; import com.google.inject.TypeLiteral; import com.google.inject.internal.util.Classes; import com.google.inject.spi.BindingTargetVisitor; import com.google.inject.spi.ConstructorBinding; import com.google.inject.spi.Dependency; import com.google.inject.spi.InjectionPoint; import java.lang.annotation.Annotation; import java.lang.reflect.Constructor; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.util.List; import java.util.Map; import java.util.Set; final class ConstructorBindingImpl<T> extends BindingImpl<T> implements ConstructorBinding<T>, DelayedInitialize { private final Factory<T> factory; private final InjectionPoint constructorInjectionPoint; private ConstructorBindingImpl(InjectorImpl injector, Key<T> key, Object source, InternalFactory<? extends T> scopedFactory, Scoping scoping, Factory<T> factory, InjectionPoint constructorInjectionPoint) { super(injector, key, source, scopedFactory, scoping); this.factory = factory; this.constructorInjectionPoint = constructorInjectionPoint; } public ConstructorBindingImpl(Key<T> key, Object source, Scoping scoping, InjectionPoint constructorInjectionPoint, Set<InjectionPoint> injectionPoints) { super(source, key, scoping); this.factory = new Factory<T>(false, key); ConstructionProxy<T> constructionProxy = new DefaultConstructionProxyFactory<T>(constructorInjectionPoint) .create(); this.constructorInjectionPoint = constructorInjectionPoint; factory.constructorInjector = new ConstructorInjector<T>(injectionPoints, constructionProxy, null, null); } /** * @param constructorInjector the constructor to use, or {@code null} to use the default. * @param failIfNotLinked true if this ConstructorBindingImpl's InternalFactory should * only succeed if retrieved from a linked binding */ static <T> ConstructorBindingImpl<T> create(InjectorImpl injector, Key<T> key, InjectionPoint constructorInjector, Object source, Scoping scoping, Errors errors, boolean failIfNotLinked, boolean failIfNotExplicit) throws ErrorsException { int numErrors = errors.size(); @SuppressWarnings("unchecked") // constructorBinding guarantees type is consistent Class<? super T> rawType = constructorInjector == null ? key.getTypeLiteral().getRawType() : (Class) constructorInjector.getDeclaringType().getRawType(); // We can't inject abstract classes. if (Modifier.isAbstract(rawType.getModifiers())) { errors.missingImplementation(key); } // Error: Inner class. if (Classes.isInnerClass(rawType)) { errors.cannotInjectInnerClass(rawType); } errors.throwIfNewErrors(numErrors); // Find a constructor annotated @Inject if (constructorInjector == null) { try { constructorInjector = InjectionPoint.forConstructorOf(key.getTypeLiteral()); if (failIfNotExplicit && !hasAtInject((Constructor) constructorInjector.getMember())) { errors.atInjectRequired(rawType); } } catch (ConfigurationException e) { throw errors.merge(e.getErrorMessages()).toException(); } } // if no scope is specified, look for a scoping annotation on the concrete class if (!scoping.isExplicitlyScoped()) { Class<?> annotatedType = constructorInjector.getMember().getDeclaringClass(); Class<? extends Annotation> scopeAnnotation = findScopeAnnotation(errors, annotatedType); if (scopeAnnotation != null) { scoping = Scoping.makeInjectable(Scoping.forAnnotation(scopeAnnotation), injector, errors.withSource(rawType)); } } errors.throwIfNewErrors(numErrors); Factory<T> factoryFactory = new Factory<T>(failIfNotLinked, key); InternalFactory<? extends T> scopedFactory = Scoping.scope(key, injector, factoryFactory, source, scoping); return new ConstructorBindingImpl<T>(injector, key, source, scopedFactory, scoping, factoryFactory, constructorInjector); } /** Returns true if the inject annotation is on the constructor. */ private static boolean hasAtInject(Constructor cxtor) { return cxtor.isAnnotationPresent(Inject.class) || cxtor.isAnnotationPresent(javax.inject.Inject.class); } @SuppressWarnings("unchecked") // the result type always agrees with the ConstructorInjector type public void initialize(InjectorImpl injector, Errors errors) throws ErrorsException { factory.allowCircularProxy = !injector.options.disableCircularProxies; factory.constructorInjector = (ConstructorInjector<T>) injector.constructors.get(constructorInjectionPoint, errors); factory.provisionCallback = injector.provisionListenerStore.get(this); } /** True if this binding has been initialized and is ready for use. */ boolean isInitialized() { return factory.constructorInjector != null; } /** Returns an injection point that can be used to clean up the constructor store. */ InjectionPoint getInternalConstructor() { if (factory.constructorInjector != null) { return factory.constructorInjector.getConstructionProxy().getInjectionPoint(); } else { return constructorInjectionPoint; } } /** Returns a set of dependencies that can be iterated over to clean up stray JIT bindings. */ Set<Dependency<?>> getInternalDependencies() { ImmutableSet.Builder<InjectionPoint> builder = ImmutableSet.builder(); if (factory.constructorInjector == null) { builder.add(constructorInjectionPoint); // If the below throws, it's OK -- we just ignore those dependencies, because no one // could have used them anyway. try { builder.addAll( InjectionPoint.forInstanceMethodsAndFields(constructorInjectionPoint.getDeclaringType())); } catch (ConfigurationException ignored) { } } else { builder.add(getConstructor()).addAll(getInjectableMembers()); } return Dependency.forInjectionPoints(builder.build()); } public <V> V acceptTargetVisitor(BindingTargetVisitor<? super T, V> visitor) { checkState(factory.constructorInjector != null, "not initialized"); return visitor.visit(this); } public InjectionPoint getConstructor() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getConstructionProxy().getInjectionPoint(); } public Set<InjectionPoint> getInjectableMembers() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getInjectableMembers(); } /*if[AOP]*/ public Map<Method, List<org.aopalliance.intercept.MethodInterceptor>> getMethodInterceptors() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getConstructionProxy().getMethodInterceptors(); } /*end[AOP]*/ public Set<Dependency<?>> getDependencies() { return Dependency.forInjectionPoints(new ImmutableSet.Builder<InjectionPoint>().add(getConstructor()) .addAll(getInjectableMembers()).build()); } @Override protected BindingImpl<T> withScoping(Scoping scoping) { return new ConstructorBindingImpl<T>(null, getKey(), getSource(), factory, scoping, factory, constructorInjectionPoint); } @Override protected BindingImpl<T> withKey(Key<T> key) { return new ConstructorBindingImpl<T>(null, key, getSource(), factory, getScoping(), factory, constructorInjectionPoint); } @Override public BindingImpl<T> withRehashedKeys() { if (needsRehashing(getKey())) { return withKey(rehash(getKey())); } else { return this; } } @SuppressWarnings("unchecked") // the raw constructor member and declaring type always agree public void applyTo(Binder binder) { InjectionPoint constructor = getConstructor(); getScoping().applyTo(binder.withSource(getSource()).bind(getKey()).toConstructor( (Constructor) getConstructor().getMember(), (TypeLiteral) constructor.getDeclaringType())); } @Override public String toString() { return Objects.toStringHelper(ConstructorBinding.class).add("key", getKey()).add("source", getSource()) .add("scope", getScoping()).toString(); } @Override public boolean equals(Object obj) { if (obj instanceof ConstructorBindingImpl) { ConstructorBindingImpl<?> o = (ConstructorBindingImpl<?>) obj; return getKey().equals(o.getKey()) && getScoping().equals(o.getScoping()) && Objects.equal(constructorInjectionPoint, o.constructorInjectionPoint); } else { return false; } } @Override public int hashCode() { return Objects.hashCode(getKey(), getScoping(), constructorInjectionPoint); } private static class Factory<T> implements InternalFactory<T> { private final boolean failIfNotLinked; private final Key<?> key; private boolean allowCircularProxy; private ConstructorInjector<T> constructorInjector; private ProvisionListenerStackCallback<T> provisionCallback; Factory(boolean failIfNotLinked, Key<?> key) { this.failIfNotLinked = failIfNotLinked; this.key = key; } @SuppressWarnings("unchecked") public T get(Errors errors, InternalContext context, Dependency<?> dependency, boolean linked) throws ErrorsException { checkState(constructorInjector != null, "Constructor not ready"); if (failIfNotLinked && !linked) { throw errors.jitDisabled(key).toException(); } // This may not actually be safe because it could return a super type of T (if that's all the // client needs), but it should be OK in practice thanks to the wonders of erasure. return (T) constructorInjector.construct(errors, context, dependency.getKey().getTypeLiteral().getRawType(), allowCircularProxy, provisionCallback); } } }