| /* |
| * Copyright (C) 2018 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.squareup.javapoet.MethodSpec.constructorBuilder; |
| import static com.squareup.javapoet.MethodSpec.methodBuilder; |
| import static com.squareup.javapoet.TypeSpec.classBuilder; |
| import static dagger.internal.codegen.langmodel.Accessibility.isElementAccessibleFrom; |
| import static javax.lang.model.element.Modifier.ABSTRACT; |
| import static javax.lang.model.element.Modifier.FINAL; |
| import static javax.lang.model.element.Modifier.PRIVATE; |
| import static javax.lang.model.element.Modifier.PUBLIC; |
| import static javax.lang.model.element.Modifier.STATIC; |
| import static javax.lang.model.util.ElementFilter.constructorsIn; |
| |
| import com.squareup.javapoet.ClassName; |
| import com.squareup.javapoet.CodeBlock; |
| import com.squareup.javapoet.TypeSpec; |
| import dagger.internal.codegen.base.SourceFileGenerator; |
| import dagger.internal.codegen.binding.ModuleKind; |
| import dagger.internal.codegen.binding.SourceFiles; |
| import dagger.internal.codegen.kotlin.KotlinMetadataUtil; |
| import dagger.internal.codegen.langmodel.Accessibility; |
| import dagger.internal.codegen.langmodel.DaggerElements; |
| import java.util.Optional; |
| import javax.annotation.processing.Filer; |
| import javax.inject.Inject; |
| import javax.lang.model.SourceVersion; |
| import javax.lang.model.element.Element; |
| import javax.lang.model.element.ExecutableElement; |
| import javax.lang.model.element.TypeElement; |
| |
| /** Convenience methods for generating and using module constructor proxy methods. */ |
| public final class ModuleProxies { |
| |
| private final DaggerElements elements; |
| private final KotlinMetadataUtil metadataUtil; |
| |
| @Inject |
| public ModuleProxies(DaggerElements elements, KotlinMetadataUtil metadataUtil) { |
| this.elements = elements; |
| this.metadataUtil = metadataUtil; |
| } |
| |
| /** Generates a {@code public static} proxy method for constructing module instances. */ |
| // TODO(dpb): See if this can become a SourceFileGenerator<ModuleDescriptor> instead. Doing so may |
| // cause ModuleProcessingStep to defer elements multiple times. |
| public static final class ModuleConstructorProxyGenerator |
| extends SourceFileGenerator<TypeElement> { |
| |
| private final ModuleProxies moduleProxies; |
| private final KotlinMetadataUtil metadataUtil; |
| |
| @Inject |
| ModuleConstructorProxyGenerator( |
| Filer filer, |
| DaggerElements elements, |
| SourceVersion sourceVersion, |
| ModuleProxies moduleProxies, |
| KotlinMetadataUtil metadataUtil) { |
| super(filer, elements, sourceVersion); |
| this.moduleProxies = moduleProxies; |
| this.metadataUtil = metadataUtil; |
| } |
| |
| @Override |
| public ClassName nameGeneratedType(TypeElement moduleElement) { |
| return moduleProxies.constructorProxyTypeName(moduleElement); |
| } |
| |
| @Override |
| public Element originatingElement(TypeElement moduleElement) { |
| return moduleElement; |
| } |
| |
| @Override |
| public Optional<TypeSpec.Builder> write(TypeElement moduleElement) { |
| ModuleKind.checkIsModule(moduleElement, metadataUtil); |
| return moduleProxies.nonPublicNullaryConstructor(moduleElement).isPresent() |
| ? Optional.of(buildProxy(moduleElement)) |
| : Optional.empty(); |
| } |
| |
| private TypeSpec.Builder buildProxy(TypeElement moduleElement) { |
| return classBuilder(nameGeneratedType(moduleElement)) |
| .addModifiers(PUBLIC, FINAL) |
| .addMethod(constructorBuilder().addModifiers(PRIVATE).build()) |
| .addMethod( |
| methodBuilder("newInstance") |
| .addModifiers(PUBLIC, STATIC) |
| .returns(ClassName.get(moduleElement)) |
| .addStatement("return new $T()", moduleElement) |
| .build()); |
| } |
| } |
| |
| /** The name of the class that hosts the module constructor proxy method. */ |
| private ClassName constructorProxyTypeName(TypeElement moduleElement) { |
| ModuleKind.checkIsModule(moduleElement, metadataUtil); |
| ClassName moduleClassName = ClassName.get(moduleElement); |
| return moduleClassName |
| .topLevelClassName() |
| .peerClass(SourceFiles.classFileName(moduleClassName) + "_Proxy"); |
| } |
| |
| /** |
| * The module constructor being proxied. A proxy is generated if it is not publicly accessible and |
| * has no arguments. If an implicit reference to the enclosing class exists, or the module is |
| * abstract, no proxy method can be generated. |
| */ |
| private Optional<ExecutableElement> nonPublicNullaryConstructor(TypeElement moduleElement) { |
| ModuleKind.checkIsModule(moduleElement, metadataUtil); |
| if (moduleElement.getModifiers().contains(ABSTRACT) |
| || (moduleElement.getNestingKind().isNested() |
| && !moduleElement.getModifiers().contains(STATIC))) { |
| return Optional.empty(); |
| } |
| return constructorsIn(elements.getAllMembers(moduleElement)).stream() |
| .filter(constructor -> !Accessibility.isElementPubliclyAccessible(constructor)) |
| .filter(constructor -> !constructor.getModifiers().contains(PRIVATE)) |
| .filter(constructor -> constructor.getParameters().isEmpty()) |
| .findAny(); |
| } |
| |
| /** |
| * Returns a code block that creates a new module instance, either by invoking the nullary |
| * constructor if it's accessible from {@code requestingClass} or else by invoking the |
| * constructor's generated proxy method. |
| */ |
| public CodeBlock newModuleInstance(TypeElement moduleElement, ClassName requestingClass) { |
| ModuleKind.checkIsModule(moduleElement, metadataUtil); |
| String packageName = requestingClass.packageName(); |
| return nonPublicNullaryConstructor(moduleElement) |
| .filter(constructor -> !isElementAccessibleFrom(constructor, packageName)) |
| .map( |
| constructor -> |
| CodeBlock.of("$T.newInstance()", constructorProxyTypeName(moduleElement))) |
| .orElse(CodeBlock.of("new $T()", moduleElement)); |
| } |
| } |