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 package com.google.inject.daggeradapter; 17 18 import com.google.common.collect.ImmutableSet; 19 import com.google.inject.Binder; 20 import com.google.inject.Key; 21 import com.google.inject.internal.UniqueAnnotations; 22 import com.google.inject.multibindings.Multibinder; 23 import com.google.inject.spi.InjectionPoint; 24 import com.google.inject.spi.ModuleAnnotatedMethodScanner; 25 import dagger.Provides; 26 import dagger.Provides.Type; 27 import dagger.multibindings.ElementsIntoSet; 28 import dagger.multibindings.IntoMap; 29 import dagger.multibindings.IntoSet; 30 import java.lang.annotation.Annotation; 31 import java.lang.reflect.Method; 32 import java.util.Set; 33 34 /** 35 * A scanner to process provider methods on Dagger modules. 36 * 37 * @author cgruber (at) google.com (Christian Gruber) 38 */ 39 final class DaggerMethodScanner extends ModuleAnnotatedMethodScanner { 40 static final DaggerMethodScanner INSTANCE = new DaggerMethodScanner(); 41 private static final ImmutableSet<Class<Provides>> ANNOTATIONS = 42 ImmutableSet.of(dagger.Provides.class); 43 44 @Override 45 public Set<? extends Class<? extends Annotation>> annotationClasses() { 46 return ANNOTATIONS; 47 } 48 49 @Override 50 public <T> Key<T> prepareMethod( 51 Binder binder, Annotation rawAnnotation, Key<T> key, InjectionPoint injectionPoint) { 52 Method providesMethod = (Method) injectionPoint.getMember(); 53 Provides annotation = (Provides) rawAnnotation; 54 if (providesMethod.isAnnotationPresent(IntoSet.class)) { 55 return processSetBinding(binder, key); 56 } else if (providesMethod.isAnnotationPresent(ElementsIntoSet.class)) { 57 binder.addError("@ElementsIntoSet contributions are not suppored by Guice.", providesMethod); 58 return key; 59 } else if (providesMethod.isAnnotationPresent(IntoMap.class)) { 60 /* TODO(cgruber) implement map bindings */ 61 binder.addError("Map bindings are not yet supported."); 62 return key; 63 } 64 65 switch (annotation.type()) { 66 case UNIQUE: 67 return key; 68 case SET: 69 return processSetBinding(binder, key); 70 case SET_VALUES: 71 binder.addError( 72 Type.SET_VALUES.name() + " contributions are not supported by Guice.", providesMethod); 73 return key; 74 default: 75 binder.addError("Unknown @Provides type " + annotation.type() + ".", providesMethod); 76 return key; 77 } 78 } 79 80 private static <T> Key<T> processSetBinding(Binder binder, Key<T> key) { 81 Annotation annotation = key.getAnnotation(); 82 Multibinder<T> setBinder = 83 (annotation != null) 84 ? Multibinder.newSetBinder(binder, key.getTypeLiteral(), annotation) 85 : Multibinder.newSetBinder(binder, key.getTypeLiteral()); 86 Key<T> newKey = Key.get(key.getTypeLiteral(), UniqueAnnotations.create()); 87 setBinder.addBinding().to(newKey); 88 return newKey; 89 } 90 91 private DaggerMethodScanner() {} 92 } 93