1 /* 2 * Copyright (C) 2021 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.spi.model; 18 19 import com.google.common.collect.ImmutableSet; 20 import dagger.spi.model.BindingGraph.MaybeBinding; 21 import java.util.Optional; 22 23 /** 24 * The association between a {@link Key} and the way in which instances of the key are provided. 25 * Includes any {@linkplain DependencyRequest dependencies} that are needed in order to provide the 26 * instances. 27 * 28 * <p>If a binding is owned by more than one component, there is one {@code Binding} for every 29 * owning component. 30 */ 31 public interface Binding extends MaybeBinding { 32 @Override componentPath()33 ComponentPath componentPath(); 34 35 /** @deprecated This always returns {@code Optional.of(this)}. */ 36 @Override 37 @Deprecated binding()38 default Optional<Binding> binding() { 39 return Optional.of(this); 40 } 41 /** 42 * The dependencies of this binding. The order of the dependencies corresponds to the order in 43 * which they will be injected when the binding is requested. 44 */ dependencies()45 ImmutableSet<DependencyRequest> dependencies(); 46 47 /** 48 * The {@link DaggerElement} that declares this binding. Absent for 49 * {@linkplain BindingKind binding kinds} that are not always declared by exactly one element. 50 * 51 * <p>For example, consider {@link BindingKind#MULTIBOUND_SET}. A component with many 52 * {@code @IntoSet} bindings for the same key will have a synthetic binding that depends on all 53 * contributions, but with no identifiying binding element. A {@code @Multibinds} method will also 54 * contribute a synthetic binding, but since multiple {@code @Multibinds} methods can coexist in 55 * the same component (and contribute to one single binding), it has no binding element. 56 */ bindingElement()57 Optional<DaggerElement> bindingElement(); 58 59 /** 60 * The {@link DaggerTypeElement} of the module which contributes this binding. Absent for bindings 61 * that have no {@link #bindingElement() binding element}. 62 */ contributingModule()63 Optional<DaggerTypeElement> contributingModule(); 64 65 /** 66 * Returns {@code true} if using this binding requires an instance of the {@link 67 * #contributingModule()}. 68 */ requiresModuleInstance()69 boolean requiresModuleInstance(); 70 71 /** The scope of this binding if it has one. */ scope()72 Optional<Scope> scope(); 73 74 /** 75 * Returns {@code true} if this binding may provide {@code null} instead of an instance of {@link 76 * #key()}. Nullable bindings cannot be requested from {@linkplain DependencyRequest#isNullable() 77 * non-nullable dependency requests}. 78 */ isNullable()79 boolean isNullable(); 80 81 /** Returns {@code true} if this is a production binding, e.g. an {@code @Produces} method. */ isProduction()82 boolean isProduction(); 83 84 /** The kind of binding this instance represents. */ kind()85 BindingKind kind(); 86 87 } 88