/*
* Copyright 2002-2017 the original author or 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 org.springframework.context.index;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import javax.annotation.processing.Completion;
import javax.annotation.processing.ProcessingEnvironment;
import javax.annotation.processing.Processor;
import javax.annotation.processing.RoundEnvironment;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.Element;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.TypeElement;
/**
* Annotation {@link Processor} that writes {@link CandidateComponentsMetadata}
* file for spring components.
*
* @author Stephane Nicoll
* @author Juergen Hoeller
* @since 5.0
*/
public class CandidateComponentsIndexer implements Processor {
private MetadataStore metadataStore;
private MetadataCollector metadataCollector;
private TypeHelper typeHelper;
private List<StereotypesProvider> stereotypesProviders;
@Override
public Set<String> getSupportedOptions() {
return Collections.emptySet();
}
@Override
public Set<String> getSupportedAnnotationTypes() {
return Collections.singleton("*");
}
@Override
public SourceVersion getSupportedSourceVersion() {
return SourceVersion.latest();
}
@Override
public synchronized void init(ProcessingEnvironment env) {
this.stereotypesProviders = getStereotypesProviders(env);
this.typeHelper = new TypeHelper(env);
this.metadataStore = new MetadataStore(env);
this.metadataCollector = new MetadataCollector(env, this.metadataStore.readMetadata());
}
@Override
public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
this.metadataCollector.processing(roundEnv);
roundEnv.getRootElements().forEach(this::processElement);
if (roundEnv.processingOver()) {
writeMetaData();
}
return false;
}
@Override
public Iterable<? extends Completion> getCompletions(
Element element, AnnotationMirror annotation, ExecutableElement member, String userText) {
return Collections.emptyList();
}
private List<StereotypesProvider> getStereotypesProviders(ProcessingEnvironment env) {
List<StereotypesProvider> result = new ArrayList<>();
TypeHelper typeHelper = new TypeHelper(env);
result.add(new IndexedStereotypesProvider(typeHelper));
result.add(new StandardStereotypesProvider(typeHelper));
result.add(new PackageInfoStereotypesProvider());
return result;
}
private void processElement(Element element) {
Set<String> stereotypes = new LinkedHashSet<>();
this.stereotypesProviders.forEach(p -> stereotypes.addAll(p.getStereotypes(element)));
if (!stereotypes.isEmpty()) {
this.metadataCollector.add(new ItemMetadata(this.typeHelper.getType(element), stereotypes));
}
}
private CandidateComponentsMetadata writeMetaData() {
CandidateComponentsMetadata metadata = this.metadataCollector.getMetadata();
if (!metadata.getItems().isEmpty()) {
try {
this.metadataStore.writeMetadata(metadata);
}
catch (IOException ex) {
throw new IllegalStateException("Failed to write metadata", ex);
}
return metadata;
}
return null;
}
}