| /* |
| * Copyright 2013 Google LLC |
| * |
| * 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 com.google.auto.factory.processor; |
| |
| import static com.google.auto.common.MoreElements.isAnnotationPresent; |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static javax.lang.model.element.Modifier.ABSTRACT; |
| import static javax.lang.model.element.Modifier.PUBLIC; |
| import static javax.tools.Diagnostic.Kind.ERROR; |
| |
| import com.google.auto.common.MoreElements; |
| import com.google.auto.factory.AutoFactory; |
| import com.google.auto.factory.Provided; |
| import com.google.common.base.Function; |
| import com.google.common.base.Functions; |
| import com.google.common.base.Optional; |
| import com.google.common.base.Predicate; |
| import com.google.common.collect.FluentIterable; |
| import com.google.common.collect.ImmutableListMultimap; |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.collect.Multimaps; |
| import javax.annotation.processing.Messager; |
| import javax.lang.model.element.AnnotationMirror; |
| 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.element.VariableElement; |
| import javax.lang.model.util.ElementKindVisitor6; |
| import javax.lang.model.util.Types; |
| |
| /** |
| * A service that traverses an element and returns the set of factory methods defined therein. |
| * |
| * @author Gregory Kick |
| */ |
| final class FactoryDescriptorGenerator { |
| private final Messager messager; |
| private final Types types; |
| private final AutoFactoryDeclaration.Factory declarationFactory; |
| |
| FactoryDescriptorGenerator( |
| Messager messager, |
| Types types, |
| AutoFactoryDeclaration.Factory declarationFactory) { |
| this.messager = messager; |
| this.types = types; |
| this.declarationFactory = declarationFactory; |
| } |
| |
| ImmutableSet<FactoryMethodDescriptor> generateDescriptor(Element element) { |
| final AnnotationMirror mirror = Mirrors.getAnnotationMirror(element, AutoFactory.class).get(); |
| final Optional<AutoFactoryDeclaration> declaration = declarationFactory.createIfValid(element); |
| if (!declaration.isPresent()) { |
| return ImmutableSet.of(); |
| } |
| return element.accept(new ElementKindVisitor6<ImmutableSet<FactoryMethodDescriptor>, Void>() { |
| @Override |
| protected ImmutableSet<FactoryMethodDescriptor> defaultAction(Element e, Void p) { |
| throw new AssertionError("@AutoFactory applied to an impossible element"); |
| } |
| |
| @Override |
| public ImmutableSet<FactoryMethodDescriptor> visitTypeAsClass(TypeElement type, Void p) { |
| if (type.getModifiers().contains(ABSTRACT)) { |
| // applied to an abstract factory |
| messager.printMessage(ERROR, |
| "Auto-factory doesn't support being applied to abstract classes.", type, mirror); |
| return ImmutableSet.of(); |
| } else { |
| // applied to the type to be created |
| ImmutableSet<ExecutableElement> constructors = Elements2.getConstructors(type); |
| if (constructors.isEmpty()) { |
| return generateDescriptorForDefaultConstructor(declaration.get(), type); |
| } else { |
| return FluentIterable.from(constructors) |
| .transform(new Function<ExecutableElement, FactoryMethodDescriptor>() { |
| @Override public FactoryMethodDescriptor apply(ExecutableElement constructor) { |
| return generateDescriptorForConstructor(declaration.get(), constructor); |
| } |
| }) |
| .toSet(); |
| } |
| } |
| } |
| |
| @Override |
| public ImmutableSet<FactoryMethodDescriptor> visitTypeAsInterface(TypeElement type, Void p) { |
| // applied to the factory interface |
| messager.printMessage(ERROR, |
| "Auto-factory doesn't support being applied to interfaces.", type, mirror); |
| return ImmutableSet.of(); |
| } |
| |
| @Override |
| public ImmutableSet<FactoryMethodDescriptor> visitExecutableAsConstructor(ExecutableElement e, |
| Void p) { |
| // applied to a constructor of a type to be created |
| return ImmutableSet.of(generateDescriptorForConstructor(declaration.get(), e)); |
| } |
| }, null); |
| } |
| |
| FactoryMethodDescriptor generateDescriptorForConstructor(final AutoFactoryDeclaration declaration, |
| ExecutableElement constructor) { |
| checkNotNull(constructor); |
| checkArgument(constructor.getKind() == ElementKind.CONSTRUCTOR); |
| TypeElement classElement = MoreElements.asType(constructor.getEnclosingElement()); |
| ImmutableListMultimap<Boolean, ? extends VariableElement> parameterMap = |
| Multimaps.index(constructor.getParameters(), Functions.forPredicate( |
| new Predicate<VariableElement>() { |
| @Override |
| public boolean apply(VariableElement parameter) { |
| return isAnnotationPresent(parameter, Provided.class); |
| } |
| })); |
| ImmutableSet<Parameter> providedParameters = |
| Parameter.forParameterList(parameterMap.get(true), types); |
| ImmutableSet<Parameter> passedParameters = |
| Parameter.forParameterList(parameterMap.get(false), types); |
| return FactoryMethodDescriptor.builder(declaration) |
| .name("create") |
| .returnType(classElement.asType()) |
| .publicMethod(classElement.getModifiers().contains(PUBLIC)) |
| .providedParameters(providedParameters) |
| .passedParameters(passedParameters) |
| .creationParameters(Parameter.forParameterList(constructor.getParameters(), types)) |
| .isVarArgs(constructor.isVarArgs()) |
| .build(); |
| } |
| |
| private ImmutableSet<FactoryMethodDescriptor> generateDescriptorForDefaultConstructor( |
| AutoFactoryDeclaration declaration, TypeElement type) { |
| return ImmutableSet.of( |
| FactoryMethodDescriptor.builder(declaration) |
| .name("create") |
| .returnType(type.asType()) |
| .publicMethod(type.getModifiers().contains(PUBLIC)) |
| .passedParameters(ImmutableSet.<Parameter>of()) |
| .creationParameters(ImmutableSet.<Parameter>of()) |
| .providedParameters(ImmutableSet.<Parameter>of()) |
| .build()); |
| } |
| } |