State.java

/*
 * Copyright (C) 2008 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.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.inject.Binding;
import com.google.inject.Key;
import com.google.inject.Scope;
import com.google.inject.TypeLiteral;
import com.google.inject.spi.ModuleAnnotatedMethodScannerBinding;
import com.google.inject.spi.ProvisionListenerBinding;
import com.google.inject.spi.ScopeBinding;
import com.google.inject.spi.TypeConverterBinding;
import com.google.inject.spi.TypeListenerBinding;
import java.lang.annotation.Annotation;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * The inheritable data within an injector. This class is intended to allow parent and local
 * injector data to be accessed as a unit.
 *
 * @author jessewilson@google.com (Jesse Wilson)
 */
interface State {

  static final State NONE =
      new State() {
        @Override
        public State parent() {
          throw new UnsupportedOperationException();
        }

        @Override
        public <T> BindingImpl<T> getExplicitBinding(Key<T> key) {
          return null;
        }

        @Override
        public Map<Key<?>, Binding<?>> getExplicitBindingsThisLevel() {
          throw new UnsupportedOperationException();
        }

        @Override
        public void putBinding(Key<?> key, BindingImpl<?> binding) {
          throw new UnsupportedOperationException();
        }

        @Override
        public ScopeBinding getScopeBinding(Class<? extends Annotation> scopingAnnotation) {
          return null;
        }

        @Override
        public void putScopeBinding(
            Class<? extends Annotation> annotationType, ScopeBinding scope) {
          throw new UnsupportedOperationException();
        }

        @Override
        public void addConverter(TypeConverterBinding typeConverterBinding) {
          throw new UnsupportedOperationException();
        }

        @Override
        public TypeConverterBinding getConverter(
            String stringValue, TypeLiteral<?> type, Errors errors, Object source) {
          throw new UnsupportedOperationException();
        }

        @Override
        public Iterable<TypeConverterBinding> getConvertersThisLevel() {
          return ImmutableSet.of();
        }

        /*if[AOP]*/
        @Override
        public void addMethodAspect(MethodAspect methodAspect) {
          throw new UnsupportedOperationException();
        }

        @Override
        public ImmutableList<MethodAspect> getMethodAspects() {
          return ImmutableList.of();
        }
        /*end[AOP]*/

        @Override
        public void addTypeListener(TypeListenerBinding typeListenerBinding) {
          throw new UnsupportedOperationException();
        }

        @Override
        public List<TypeListenerBinding> getTypeListenerBindings() {
          return ImmutableList.of();
        }

        @Override
        public void addProvisionListener(ProvisionListenerBinding provisionListenerBinding) {
          throw new UnsupportedOperationException();
        }

        @Override
        public List<ProvisionListenerBinding> getProvisionListenerBindings() {
          return ImmutableList.of();
        }

        @Override
        public void addScanner(ModuleAnnotatedMethodScannerBinding scanner) {
          throw new UnsupportedOperationException();
        }

        @Override
        public List<ModuleAnnotatedMethodScannerBinding> getScannerBindings() {
          return ImmutableList.of();
        }

        @Override
        public void blacklist(Key<?> key, State state, Object source) {}

        @Override
        public boolean isBlacklisted(Key<?> key) {
          return true;
        }

        @Override
        public Set<Object> getSourcesForBlacklistedKey(Key<?> key) {
          throw new UnsupportedOperationException();
        }

        @Override
        public Object lock() {
          throw new UnsupportedOperationException();
        }

        public Object singletonCreationLock() {
          throw new UnsupportedOperationException();
        }

        @Override
        public Map<Class<? extends Annotation>, Scope> getScopes() {
          return ImmutableMap.of();
        }
      };

  State parent();

  /** Gets a binding which was specified explicitly in a module, or null. */
  <T> BindingImpl<T> getExplicitBinding(Key<T> key);

  /** Returns the explicit bindings at this level only. */
  Map<Key<?>, Binding<?>> getExplicitBindingsThisLevel();

  void putBinding(Key<?> key, BindingImpl<?> binding);

  ScopeBinding getScopeBinding(Class<? extends Annotation> scopingAnnotation);

  void putScopeBinding(Class<? extends Annotation> annotationType, ScopeBinding scope);

  void addConverter(TypeConverterBinding typeConverterBinding);

  /** Returns the matching converter for {@code type}, or null if none match. */
  TypeConverterBinding getConverter(
      String stringValue, TypeLiteral<?> type, Errors errors, Object source);

  /** Returns all converters at this level only. */
  Iterable<TypeConverterBinding> getConvertersThisLevel();

  /*if[AOP]*/
  void addMethodAspect(MethodAspect methodAspect);

  ImmutableList<MethodAspect> getMethodAspects();
  /*end[AOP]*/

  void addTypeListener(TypeListenerBinding typeListenerBinding);

  List<TypeListenerBinding> getTypeListenerBindings();

  void addProvisionListener(ProvisionListenerBinding provisionListenerBinding);

  List<ProvisionListenerBinding> getProvisionListenerBindings();

  void addScanner(ModuleAnnotatedMethodScannerBinding scanner);

  List<ModuleAnnotatedMethodScannerBinding> getScannerBindings();

  /**
   * Forbids the corresponding injector from creating a binding to {@code key}. Child injectors
   * blacklist their bound keys on their parent injectors to prevent just-in-time bindings on the
   * parent injector that would conflict and pass along their state to control the lifetimes.
   */
  void blacklist(Key<?> key, State state, Object source);

  /**
   * Returns true if {@code key} is forbidden from being bound in this injector. This indicates that
   * one of this injector's descendent's has bound the key.
   */
  boolean isBlacklisted(Key<?> key);

  /** Returns the source of a blacklisted key. */
  Set<Object> getSourcesForBlacklistedKey(Key<?> key);

  /**
   * Returns the shared lock for all injector data. This is a low-granularity, high-contention lock
   * to be used when reading mutable data (ie. just-in-time bindings, and binding blacklists).
   */
  Object lock();

  /** Returns all the scope bindings at this level and parent levels. */
  Map<Class<? extends Annotation>, Scope> getScopes();
}