1 /* 2 * Copyright (C) 2018 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.internal.codegen.writing; 18 19 import static com.google.common.collect.Iterables.getOnlyElement; 20 import static dagger.internal.codegen.binding.BindingRequest.bindingRequest; 21 22 import com.squareup.javapoet.CodeBlock; 23 import dagger.internal.codegen.binding.ContributionBinding; 24 import dagger.internal.codegen.writing.FrameworkFieldInitializer.FrameworkInstanceCreationExpression; 25 26 /** 27 * A {@link FrameworkInstanceCreationExpression} for {@link dagger.model.BindingKind#OPTIONAL 28 * optional bindings}. 29 */ 30 final class OptionalFactoryInstanceCreationExpression 31 implements FrameworkInstanceCreationExpression { 32 private final OptionalFactories optionalFactories; 33 private final ContributionBinding binding; 34 private final ComponentImplementation componentImplementation; 35 private final ComponentBindingExpressions componentBindingExpressions; 36 OptionalFactoryInstanceCreationExpression( OptionalFactories optionalFactories, ContributionBinding binding, ComponentImplementation componentImplementation, ComponentBindingExpressions componentBindingExpressions)37 OptionalFactoryInstanceCreationExpression( 38 OptionalFactories optionalFactories, 39 ContributionBinding binding, 40 ComponentImplementation componentImplementation, 41 ComponentBindingExpressions componentBindingExpressions) { 42 this.optionalFactories = optionalFactories; 43 this.binding = binding; 44 this.componentImplementation = componentImplementation; 45 this.componentBindingExpressions = componentBindingExpressions; 46 } 47 48 @Override creationExpression()49 public CodeBlock creationExpression() { 50 return binding.dependencies().isEmpty() 51 ? optionalFactories.absentOptionalProvider(binding) 52 : optionalFactories.presentOptionalFactory( 53 binding, 54 componentBindingExpressions 55 .getDependencyExpression( 56 bindingRequest( 57 getOnlyElement(binding.dependencies()).key(), binding.frameworkType()), 58 componentImplementation.name()) 59 .codeBlock()); 60 } 61 62 @Override useInnerSwitchingProvider()63 public boolean useInnerSwitchingProvider() { 64 // Share providers for empty optionals from OptionalFactories so we don't have numerous 65 // switch cases that all return Optional.empty(). 66 return !binding.dependencies().isEmpty(); 67 } 68 } 69