1 /** 2 * Copyright (C) 2015 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.inject.multibindings; 18 19 import static java.lang.annotation.ElementType.METHOD; 20 import static java.lang.annotation.RetentionPolicy.RUNTIME; 21 22 import com.google.inject.Module; 23 24 import java.lang.annotation.Documented; 25 import java.lang.annotation.Retention; 26 import java.lang.annotation.Target; 27 28 /** 29 * Annotates methods of a {@link Module} to add items to a {@link MapBinder}. 30 * The method's return type, binding annotation and additional key annotation determines 31 * what Map this will contribute to. For example, 32 * 33 * <pre> 34 * {@literal @}ProvidesIntoMap 35 * {@literal @}StringMapKey("Foo") 36 * {@literal @}Named("plugins") 37 * Plugin provideFooUrl(FooManager fm) { returm fm.getPlugin(); } 38 * 39 * {@literal @}ProvidesIntoMap 40 * {@literal @}StringMapKey("Bar") 41 * {@literal @}Named("urls") 42 * Plugin provideBarUrl(BarManager bm) { return bm.getPlugin(); } 43 * </pre> 44 * 45 * will add two items to the {@code @Named("urls") Map<String, Plugin>} map. The key 'Foo' 46 * will map to the provideFooUrl method, and the key 'Bar' will map to the provideBarUrl method. 47 * The values are bound as providers and will be evaluated at injection time. 48 * 49 * <p>Because the key is specified as an annotation, only Strings, Classes, enums, primitive 50 * types and annotation instances are supported as keys. 51 * 52 * @author sameb@google.com (Sam Berlin) 53 * @since 4.0 54 */ 55 @Documented 56 @Target(METHOD) 57 @Retention(RUNTIME) 58 public @interface ProvidesIntoMap { 59 } 60