core/src/com/google/inject/spi/ElementVisitor.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.spi;

import com.google.inject.Binder;
import com.google.inject.Binding;
import com.google.inject.Inject;

/**
 * Visit elements.
 *
 * @param <V> any type to be returned by the visit method. Use {@link Void} with {@code return null}
 *     if no return type is needed.
 * @since 2.0
 */
public interface ElementVisitor<V> {

  /**
   * Visit a mapping from a key (type and optional annotation) to the strategy for getting instances
   * of the type.
   */
  <T> V visit(Binding<T> binding);

  /*if[AOP]*/
  /** Visit a registration of interceptors for matching methods of matching classes. */
  V visit(InterceptorBinding binding);
  /*end[AOP]*/

  /** Visit a registration of a scope annotation with the scope that implements it. */
  V visit(ScopeBinding binding);

  /** Visit a registration of type converters for matching target types. */
  V visit(TypeConverterBinding binding);

  /** Visit a request to inject the instance fields and methods of an instance. */
  V visit(InjectionRequest<?> request);

  /** Visit a request to inject the static fields and methods of type. */
  V visit(StaticInjectionRequest request);

  /** Visit a lookup of the provider for a type. */
  <T> V visit(ProviderLookup<T> lookup);

  /** Visit a lookup of the members injector. */
  <T> V visit(MembersInjectorLookup<T> lookup);

  /** Visit an error message and the context in which it occured. */
  V visit(Message message);

  /**
   * Visit a collection of configuration elements for a {@linkplain com.google.inject.PrivateBinder
   * private binder}.
   */
  V visit(PrivateElements elements);

  /** Visit an injectable type listener binding. */
  V visit(TypeListenerBinding binding);

  /**
   * Visit a provision listener binding.
   *
   * @since 4.0
   */
  V visit(ProvisionListenerBinding binding);

  /**
   * Visit a require explicit bindings command.
   *
   * @since 3.0
   */
  V visit(RequireExplicitBindingsOption option);

  /**
   * Visit a disable circular proxies command.
   *
   * @since 3.0
   */
  V visit(DisableCircularProxiesOption option);

  /**
   * Visit a require explicit {@literal @}{@link Inject} command.
   *
   * @since 4.0
   */
  V visit(RequireAtInjectOnConstructorsOption option);

  /**
   * Visit a require exact binding annotations command.
   *
   * @since 4.0
   */
  V visit(RequireExactBindingAnnotationsOption option);

  /**
   * Visits a {@link Binder#scanModulesForAnnotatedMethods} command.
   *
   * @since 4.0
   */
  V visit(ModuleAnnotatedMethodScannerBinding binding);
}