gerrit-extension-api/src/main/java/com/google/gerrit/extensions/config/FactoryModule.java

// Copyright (C) 2009 The Android Open Source Project
//
// 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.gerrit.extensions.config;

import com.google.inject.AbstractModule;
import com.google.inject.assistedinject.FactoryModuleBuilder;

public abstract class FactoryModule extends AbstractModule {
  /**
   * Register an assisted injection factory.
   * <p>
   * This function provides an automatic way to define a factory that creates a
   * concrete type through assisted injection. For example to configure the
   * following assisted injection case:
   *
   * <pre>
   * public class Foo {
   *   public interface Factory {
   *     Foo create(int a);
   *   }
   *   &#064;Inject
   *   Foo(Logger log, @Assisted int a) {...}
   * }
   * </pre>
   *
   * Just pass {@code Foo.Factory.class} to this method. The factory will be
   * generated to return its one return type as declared in the creation method.
   *
   * @param factory interface which specifies the bean factory method.
   */
  protected void factory(final Class<?> factory) {
    install(new FactoryModuleBuilder().build(factory));
  }
}