| /* |
| * Copyright (C) 2014 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.binding.AnnotationExpression.createMethodName; |
| import static dagger.internal.codegen.binding.AnnotationExpression.getAnnotationCreatorClassName; |
| import static dagger.internal.codegen.javapoet.CodeBlocks.makeParametersCodeBlock; |
| 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.methodsIn; |
| |
| import com.google.auto.common.MoreTypes; |
| import com.google.common.collect.ImmutableList; |
| import com.google.errorprone.annotations.CanIgnoreReturnValue; |
| import com.squareup.javapoet.ClassName; |
| import com.squareup.javapoet.CodeBlock; |
| import com.squareup.javapoet.MethodSpec; |
| import com.squareup.javapoet.TypeName; |
| import com.squareup.javapoet.TypeSpec; |
| import dagger.internal.codegen.base.SourceFileGenerator; |
| import dagger.internal.codegen.langmodel.DaggerElements; |
| import java.util.LinkedHashSet; |
| import java.util.Optional; |
| import java.util.Set; |
| 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.ElementKind; |
| import javax.lang.model.element.ExecutableElement; |
| import javax.lang.model.element.TypeElement; |
| import javax.lang.model.type.DeclaredType; |
| import javax.lang.model.util.SimpleTypeVisitor6; |
| |
| /** |
| * Generates classes that create annotation instances for an annotation type. The generated class |
| * will have a private empty constructor, a static method that creates the annotation type itself, |
| * and a static method that creates each annotation type that is nested in the top-level annotation |
| * type. |
| * |
| * <p>So for an example annotation: |
| * |
| * <pre> |
| * {@literal @interface} Foo { |
| * String s(); |
| * int i(); |
| * Bar bar(); // an annotation defined elsewhere |
| * } |
| * </pre> |
| * |
| * the generated class will look like: |
| * |
| * <pre> |
| * public final class FooCreator { |
| * private FooCreator() {} |
| * |
| * public static Foo createFoo(String s, int i, Bar bar) { … } |
| * public static Bar createBar(…) { … } |
| * } |
| * </pre> |
| */ |
| public class AnnotationCreatorGenerator extends SourceFileGenerator<TypeElement> { |
| private static final ClassName AUTO_ANNOTATION = |
| ClassName.get("com.google.auto.value", "AutoAnnotation"); |
| |
| @Inject |
| AnnotationCreatorGenerator(Filer filer, DaggerElements elements, SourceVersion sourceVersion) { |
| super(filer, elements, sourceVersion); |
| } |
| |
| @Override |
| public ClassName nameGeneratedType(TypeElement annotationType) { |
| return getAnnotationCreatorClassName(annotationType); |
| } |
| |
| @Override |
| public Element originatingElement(TypeElement annotationType) { |
| return annotationType; |
| } |
| |
| @Override |
| public Optional<TypeSpec.Builder> write(TypeElement annotationType) { |
| ClassName generatedTypeName = nameGeneratedType(annotationType); |
| TypeSpec.Builder annotationCreatorBuilder = |
| classBuilder(generatedTypeName) |
| .addModifiers(PUBLIC, FINAL) |
| .addMethod(constructorBuilder().addModifiers(PRIVATE).build()); |
| |
| for (TypeElement annotationElement : annotationsToCreate(annotationType)) { |
| annotationCreatorBuilder.addMethod(buildCreateMethod(generatedTypeName, annotationElement)); |
| } |
| |
| return Optional.of(annotationCreatorBuilder); |
| } |
| |
| private MethodSpec buildCreateMethod(ClassName generatedTypeName, TypeElement annotationElement) { |
| String createMethodName = createMethodName(annotationElement); |
| MethodSpec.Builder createMethod = |
| methodBuilder(createMethodName) |
| .addAnnotation(AUTO_ANNOTATION) |
| .addModifiers(PUBLIC, STATIC) |
| .returns(TypeName.get(annotationElement.asType())); |
| |
| ImmutableList.Builder<CodeBlock> parameters = ImmutableList.builder(); |
| for (ExecutableElement annotationMember : methodsIn(annotationElement.getEnclosedElements())) { |
| String parameterName = annotationMember.getSimpleName().toString(); |
| TypeName parameterType = TypeName.get(annotationMember.getReturnType()); |
| createMethod.addParameter(parameterType, parameterName); |
| parameters.add(CodeBlock.of("$L", parameterName)); |
| } |
| |
| ClassName autoAnnotationClass = |
| generatedTypeName.peerClass( |
| "AutoAnnotation_" + generatedTypeName.simpleName() + "_" + createMethodName); |
| createMethod.addStatement( |
| "return new $T($L)", autoAnnotationClass, makeParametersCodeBlock(parameters.build())); |
| return createMethod.build(); |
| } |
| |
| /** |
| * Returns the annotation types for which {@code @AutoAnnotation static Foo createFoo(…)} methods |
| * should be written. |
| */ |
| protected Set<TypeElement> annotationsToCreate(TypeElement annotationElement) { |
| return nestedAnnotationElements(annotationElement, new LinkedHashSet<>()); |
| } |
| |
| @CanIgnoreReturnValue |
| private static Set<TypeElement> nestedAnnotationElements( |
| TypeElement annotationElement, Set<TypeElement> annotationElements) { |
| if (annotationElements.add(annotationElement)) { |
| for (ExecutableElement method : methodsIn(annotationElement.getEnclosedElements())) { |
| TRAVERSE_NESTED_ANNOTATIONS.visit(method.getReturnType(), annotationElements); |
| } |
| } |
| return annotationElements; |
| } |
| |
| private static final SimpleTypeVisitor6<Void, Set<TypeElement>> TRAVERSE_NESTED_ANNOTATIONS = |
| new SimpleTypeVisitor6<Void, Set<TypeElement>>() { |
| @Override |
| public Void visitDeclared(DeclaredType t, Set<TypeElement> p) { |
| TypeElement typeElement = MoreTypes.asTypeElement(t); |
| if (typeElement.getKind() == ElementKind.ANNOTATION_TYPE) { |
| nestedAnnotationElements(typeElement, p); |
| } |
| return null; |
| } |
| }; |
| } |