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.spi; 18 19 import com.google.inject.Binder; 20 import com.google.inject.Key; 21 import java.lang.annotation.Annotation; 22 import java.util.Set; 23 24 /** 25 * Allows extensions to scan modules for annotated methods and bind those methods as providers, 26 * similar to {@code @Provides} methods. 27 * 28 * @since 4.0 29 */ 30 public abstract class ModuleAnnotatedMethodScanner { 31 32 /** 33 * Returns the annotations this should scan for. Every method in the module that has one of these 34 * annotations will create a Provider binding, with the return value of the binding being what's 35 * provided and the parameters of the method being dependencies of the provider. 36 */ annotationClasses()37 public abstract Set<? extends Class<? extends Annotation>> annotationClasses(); 38 39 /** 40 * Prepares a method for binding. This {@code key} parameter is the key discovered from looking at 41 * the binding annotation and return value of the method. Implementations can modify the key to 42 * instead bind to another key. For example, Multibinder may want to change {@code @SetProvides 43 * String provideFoo()} to bind into a unique Key within the multibinder instead of binding {@code 44 * String}. 45 * 46 * <p>The injection point and annotation are provided in case the implementation wants to set the 47 * key based on the property of the annotation or if any additional preparation is needed for any 48 * of the dependencies. The annotation is guaranteed to be an instance of one the classes returned 49 * by {@link #annotationClasses}. 50 */ prepareMethod( Binder binder, Annotation annotation, Key<T> key, InjectionPoint injectionPoint)51 public abstract <T> Key<T> prepareMethod( 52 Binder binder, Annotation annotation, Key<T> key, InjectionPoint injectionPoint); 53 } 54