1 /* 2 * Copyright (C) 2017 The Dagger Authors. 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 dagger.model; 18 19 import com.google.common.collect.ImmutableSet; 20 import dagger.model.BindingGraph.MaybeBinding; 21 import java.util.Optional; 22 import javax.lang.model.element.Element; 23 import javax.lang.model.element.TypeElement; 24 25 /** 26 * The association between a {@link Key} and the way in which instances of the key are provided. 27 * Includes any {@linkplain DependencyRequest dependencies} that are needed in order to provide the 28 * instances. 29 * 30 * <p>If a binding is owned by more than one component, there is one {@code Binding} for every 31 * owning component. 32 */ 33 public interface Binding extends MaybeBinding { 34 @Override componentPath()35 ComponentPath componentPath(); 36 37 /** @deprecated This always returns {@code Optional.of(this)}. */ 38 @Override 39 @Deprecated binding()40 default Optional<Binding> binding() { 41 return Optional.of(this); 42 } 43 /** 44 * The dependencies of this binding. The order of the dependencies corresponds to the order in 45 * which they will be injected when the binding is requested. 46 */ dependencies()47 ImmutableSet<DependencyRequest> dependencies(); 48 49 /** 50 * The {@link Element} that declares this binding. Absent for {@linkplain BindingKind binding 51 * kinds} that are not always declared by exactly one element. 52 * 53 * <p>For example, consider {@link BindingKind#MULTIBOUND_SET}. A component with many 54 * {@code @IntoSet} bindings for the same key will have a synthetic binding that depends on all 55 * contributions, but with no identifiying binding element. A {@code @Multibinds} method will also 56 * contribute a synthetic binding, but since multiple {@code @Multibinds} methods can coexist in 57 * the same component (and contribute to one single binding), it has no binding element. 58 */ bindingElement()59 Optional<Element> bindingElement(); 60 61 /** 62 * The {@link TypeElement} of the module which contributes this binding. Absent for bindings that 63 * have no {@link #bindingElement() binding element}. 64 */ contributingModule()65 Optional<TypeElement> contributingModule(); 66 67 /** 68 * Returns {@code true} if using this binding requires an instance of the {@link 69 * #contributingModule()}. 70 */ requiresModuleInstance()71 boolean requiresModuleInstance(); 72 73 /** The scope of this binding if it has one. */ scope()74 Optional<Scope> scope(); 75 76 /** 77 * Returns {@code true} if this binding may provide {@code null} instead of an instance of {@link 78 * #key()}. Nullable bindings cannot be requested from {@linkplain DependencyRequest#isNullable() 79 * non-nullable dependency requests}. 80 */ isNullable()81 boolean isNullable(); 82 83 /** Returns {@code true} if this is a production binding, e.g. an {@code @Produces} method. */ isProduction()84 boolean isProduction(); 85 86 /** The kind of binding this instance represents. */ kind()87 BindingKind kind(); 88 89 } 90