| /* |
| * Copyright (C) 2017 The Dagger Authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package dagger.internal.codegen.writing; |
| |
| import static com.google.common.collect.Iterables.getOnlyElement; |
| import static dagger.internal.codegen.binding.BindingRequest.bindingRequest; |
| import static dagger.internal.codegen.langmodel.Accessibility.isTypeAccessibleFrom; |
| |
| import com.squareup.javapoet.ClassName; |
| import com.squareup.javapoet.CodeBlock; |
| import dagger.internal.codegen.base.OptionalType; |
| import dagger.internal.codegen.base.OptionalType.OptionalKind; |
| import dagger.internal.codegen.binding.ProvisionBinding; |
| import dagger.internal.codegen.javapoet.Expression; |
| import dagger.internal.codegen.langmodel.DaggerTypes; |
| import dagger.model.DependencyRequest; |
| import javax.inject.Inject; |
| import javax.lang.model.SourceVersion; |
| |
| /** A binding expression for optional bindings. */ |
| final class OptionalBindingExpression extends SimpleInvocationBindingExpression { |
| private final ProvisionBinding binding; |
| private final ComponentBindingExpressions componentBindingExpressions; |
| private final DaggerTypes types; |
| private final SourceVersion sourceVersion; |
| |
| @Inject |
| OptionalBindingExpression( |
| ProvisionBinding binding, |
| ComponentBindingExpressions componentBindingExpressions, |
| DaggerTypes types, |
| SourceVersion sourceVersion) { |
| super(binding); |
| this.binding = binding; |
| this.componentBindingExpressions = componentBindingExpressions; |
| this.types = types; |
| this.sourceVersion = sourceVersion; |
| } |
| |
| @Override |
| Expression getDependencyExpression(ClassName requestingClass) { |
| OptionalType optionalType = OptionalType.from(binding.key()); |
| OptionalKind optionalKind = optionalType.kind(); |
| if (binding.dependencies().isEmpty()) { |
| if (sourceVersion.compareTo(SourceVersion.RELEASE_7) <= 0) { |
| // When compiling with -source 7, javac's type inference isn't strong enough to detect |
| // Futures.immediateFuture(Optional.absent()) for keys that aren't Object. It also has |
| // issues |
| // when used as an argument to some members injection proxy methods (see |
| // https://github.com/google/dagger/issues/916) |
| if (isTypeAccessibleFrom(binding.key().type(), requestingClass.packageName())) { |
| return Expression.create( |
| binding.key().type(), optionalKind.parameterizedAbsentValueExpression(optionalType)); |
| } |
| } |
| return Expression.create(binding.key().type(), optionalKind.absentValueExpression()); |
| } |
| DependencyRequest dependency = getOnlyElement(binding.dependencies()); |
| |
| CodeBlock dependencyExpression = |
| componentBindingExpressions |
| .getDependencyExpression(bindingRequest(dependency), requestingClass) |
| .codeBlock(); |
| |
| // If the dependency type is inaccessible, then we have to use Optional.<Object>of(...), or else |
| // we will get "incompatible types: inference variable has incompatible bounds. |
| return isTypeAccessibleFrom(dependency.key().type(), requestingClass.packageName()) |
| ? Expression.create( |
| binding.key().type(), optionalKind.presentExpression(dependencyExpression)) |
| : Expression.create( |
| types.erasure(binding.key().type()), |
| optionalKind.presentObjectExpression(dependencyExpression)); |
| } |
| |
| @Override |
| boolean requiresMethodEncapsulation() { |
| // TODO(dpb): Maybe require it for present bindings. |
| return false; |
| } |
| } |