/*
 * 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 com.google.common.base.MoreObjects;
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<>(false, key);
    ConstructionProxy<T> constructionProxy =
        new DefaultConstructionProxyFactory<T>(constructorInjectionPoint).create();
    this.constructorInjectionPoint = constructorInjectionPoint;
    factory.constructorInjector =
        new ConstructorInjector<T>(injectionPoints, constructionProxy, null, null);
  }

  
Params:
  • constructorInjector – the constructor to use, or null to use the default.
  • failIfNotLinked – true if this ConstructorBindingImpl's InternalFactory should only succeed if retrieved from a linked binding
/** * @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.missingImplementationWithHint(key, injector); } // 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<>(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.
/** 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); } @Override @SuppressWarnings("unchecked") // the result type always agrees with the ConstructorInjector type public void initialize(InjectorImpl injector, Errors errors) throws ErrorsException { 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.
/** 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.
/** 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.
/** 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()); } @Override public <V> V acceptTargetVisitor(BindingTargetVisitor<? super T, V> visitor) { checkState(factory.constructorInjector != null, "not initialized"); return visitor.visit(this); } @Override public InjectionPoint getConstructor() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getConstructionProxy().getInjectionPoint(); } @Override public Set<InjectionPoint> getInjectableMembers() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getInjectableMembers(); } /*if[AOP]*/ @Override public Map<Method, List<org.aopalliance.intercept.MethodInterceptor>> getMethodInterceptors() { checkState(factory.constructorInjector != null, "Binding is not ready"); return factory.constructorInjector.getConstructionProxy().getMethodInterceptors(); } /*end[AOP]*/ @Override 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 @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 MoreObjects.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 ConstructorInjector<T> constructorInjector; private ProvisionListenerStackCallback<T> provisionCallback; Factory(boolean failIfNotLinked, Key<?> key) { this.failIfNotLinked = failIfNotLinked; this.key = key; } @Override @SuppressWarnings("unchecked") public T get(InternalContext context, Dependency<?> dependency, boolean linked) throws InternalProvisionException { ConstructorInjector<T> localInjector = constructorInjector; if (localInjector == null) { throw new IllegalStateException("Constructor not ready"); } if (!linked && failIfNotLinked) { throw InternalProvisionException.jitDisabled(key); } // 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) localInjector.construct(context, dependency, provisionCallback); } } }