/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
* <p>
* http://www.apache.org/licenses/LICENSE-2.0
* <p>
* 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.apache.aries.blueprint.plugin.handlers.pax;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import org.apache.aries.blueprint.plugin.spi.BeanAnnotationHandler;
import org.apache.aries.blueprint.plugin.spi.BeanEnricher;
import org.apache.aries.blueprint.plugin.spi.ContextEnricher;
import org.apache.aries.blueprint.plugin.spi.XmlWriter;
import org.ops4j.pax.cdi.api.OsgiServiceProvider;
import org.ops4j.pax.cdi.api.Properties;
import org.ops4j.pax.cdi.api.Property;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
import java.lang.reflect.AnnotatedElement;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class OsgiServiceProviderHandler implements BeanAnnotationHandler<OsgiServiceProvider> {
private static final List<String> SPECIAL_PROPERTIES = Collections.singletonList("service.ranking");
@Override
public Class<OsgiServiceProvider> getAnnotation() {
return OsgiServiceProvider.class;
}
@Override
public void handleBeanAnnotation(AnnotatedElement annotatedElement, final String id, ContextEnricher contextEnricher, BeanEnricher beanEnricher) {
handleAnnotation(annotatedElement, id, contextEnricher);
}
private void handleAnnotation(AnnotatedElement annotatedElement, final String id, ContextEnricher contextEnricher) {
final OsgiServiceProvider serviceProvider = annotatedElement.getAnnotation(OsgiServiceProvider.class);
Properties properties = annotatedElement.getAnnotation(Properties.class);
final List<String> interfaceNames = extractServiceInterfaces(serviceProvider);
final List<ServiceProperty> serviceProperties = extractProperties(properties);
contextEnricher.addBlueprintContentWriter("OsgiServiceProvider/" + annotatedElement + "/" + id, new XmlWriter() {
@Override
public void write(XMLStreamWriter writer) throws XMLStreamException {
writeService(writer, serviceProperties, interfaceNames, id);
}
});
}
private void writeService(XMLStreamWriter writer, List<ServiceProperty> serviceProperties, List<String> interfaceNames, String id) throws XMLStreamException {
boolean writeEmptyElement = serviceProperties.isEmpty() && interfaceNames.size() < 2;
if (writeEmptyElement) {
writer.writeEmptyElement("service");
} else {
writer.writeStartElement("service");
}
writer.writeAttribute("ref", id);
if (interfaceNames.size() == 0) {
writer.writeAttribute("auto-export", "interfaces");
} else if (interfaceNames.size() == 1) {
writer.writeAttribute("interface", Iterables.getOnlyElement(interfaceNames));
} else {
writeInterfacesElement(writer, interfaceNames);
}
if (!serviceProperties.isEmpty()) {
writeRanking(writer, serviceProperties);
writeProperties(writer, serviceProperties);
}
if (!writeEmptyElement) {
writer.writeEndElement();
}
}
private static List<ServiceProperty> extractProperties(Properties properties) {
List<ServiceProperty> serviceProperties = new ArrayList<>();
if (properties != null) {
for (Property property : properties.value()) {
serviceProperties.add(new ServiceProperty(property.name(), property.value()));
}
}
return serviceProperties;
}
private static List<String> extractServiceInterfaces(OsgiServiceProvider serviceProvider) {
List<String> interfaceNames = Lists.newArrayList();
for (Class<?> serviceIf : serviceProvider.classes()) {
interfaceNames.add(serviceIf.getName());
}
return interfaceNames;
}
private void writeInterfacesElement(XMLStreamWriter writer, Iterable<String> interfaceNames) throws XMLStreamException {
writer.writeStartElement("interfaces");
for (String interfaceName : interfaceNames) {
writer.writeStartElement("value");
writer.writeCharacters(interfaceName);
writer.writeEndElement();
}
writer.writeEndElement();
}
private void writeRanking(XMLStreamWriter writer, List<ServiceProperty> serviceProperties) throws XMLStreamException {
for (ServiceProperty serviceProperty : serviceProperties) {
if ("service.ranking".equals(serviceProperty.name)) {
try {
Integer ranking = Integer.parseInt(serviceProperty.getSingleValue());
writer.writeAttribute("ranking", ranking.toString());
} catch (NumberFormatException e) {
throw new IllegalArgumentException("service.ranking property must be an integer!");
}
}
}
}
private void writeProperties(XMLStreamWriter writer, List<ServiceProperty> serviceProperties) throws XMLStreamException {
writer.writeStartElement("service-properties");
for (ServiceProperty serviceProperty : serviceProperties) {
if (!SPECIAL_PROPERTIES.contains(serviceProperty.name)) {
serviceProperty.write(writer);
}
}
writer.writeEndElement();
}
}