/*
* 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
*
* 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.apache.tuscany.sca.contribution.processor;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.util.Map;
import java.util.Set;
import javax.xml.namespace.QName;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;
import org.apache.tuscany.sca.assembly.AssemblyFactory;
import org.apache.tuscany.sca.contribution.ModelFactoryExtensionPoint;
import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
import org.apache.tuscany.sca.contribution.service.ContributionReadException;
import org.apache.tuscany.sca.contribution.service.ContributionResolveException;
import org.apache.tuscany.sca.contribution.service.ContributionWriteException;
import org.apache.tuscany.sca.contribution.util.ServiceDeclaration;
import org.apache.tuscany.sca.contribution.util.ServiceDiscovery;
import org.apache.tuscany.sca.policy.PolicyFactory;
/**
* The default implementation of an extension point for StAX artifact processors.
*
* @version $Rev: 601501 $ $Date: 2007-12-05 20:23:21 +0000 (Wed, 05 Dec 2007) $
*/
public class DefaultStAXArtifactProcessorExtensionPoint extends
DefaultArtifactProcessorExtensionPoint<StAXArtifactProcessor> implements StAXArtifactProcessorExtensionPoint {
private ModelFactoryExtensionPoint modelFactories;
private boolean loaded;
/**
* Constructs a new extension point.
*/
public DefaultStAXArtifactProcessorExtensionPoint(ModelFactoryExtensionPoint modelFactories) {
this.modelFactories = modelFactories;
}
public void addArtifactProcessor(StAXArtifactProcessor artifactProcessor) {
processorsByArtifactType.put((Object)artifactProcessor.getArtifactType(), artifactProcessor);
processorsByModelType.put(artifactProcessor.getModelType(), artifactProcessor);
}
public void removeArtifactProcessor(StAXArtifactProcessor artifactProcessor) {
processorsByArtifactType.remove((Object)artifactProcessor.getArtifactType());
processorsByModelType.remove(artifactProcessor.getModelType());
}
@Override
public StAXArtifactProcessor getProcessor(Class<?> modelType) {
loadArtifactProcessors();
return super.getProcessor(modelType);
}
@Override
public StAXArtifactProcessor getProcessor(Object artifactType) {
loadArtifactProcessors();
return super.getProcessor(artifactType);
}
private static QName getQName(String qname) {
if (qname == null) {
return null;
}
qname = qname.trim();
if (qname.startsWith("{")) {
int h = qname.indexOf('}');
if (h != -1) {
return new QName(qname.substring(1, h), qname.substring(h + 1));
}
} else {
int h = qname.indexOf('#');
if (h != -1) {
return new QName(qname.substring(0, h), qname.substring(h + 1));
}
}
throw new IllegalArgumentException("Invalid qname: "+qname);
}
private void loadArtifactProcessors() {
if (loaded)
return;
// Get the processor service declarations
Set<ServiceDeclaration> processorDeclarations;
try {
processorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(StAXArtifactProcessor.class);
} catch (IOException e) {
throw new IllegalStateException(e);
}
for (ServiceDeclaration processorDeclaration : processorDeclarations) {
Map<String, String> attributes = processorDeclaration.getAttributes();
// Load a StAX artifact processor
// Get the model qname
QName artifactType = getQName(attributes.get("qname"));
// Get the model class name
String modelTypeName = attributes.get("model");
// Get the model factory class name
String factoryName = attributes.get("factory");
// Create a processor wrapper and register it
StAXArtifactProcessor processor =
new LazyStAXArtifactProcessor(modelFactories, artifactType, modelTypeName, factoryName,
processorDeclaration);
addArtifactProcessor(processor);
}
loaded = true;
}
/**
* A wrapper around an Artifact processor class allowing lazy loading and
* initialization of artifact processors.
*/
private static class LazyStAXArtifactProcessor implements StAXArtifactProcessor {
private ModelFactoryExtensionPoint modelFactories;
private QName artifactType;
private String modelTypeName;
private String factoryName;
private ServiceDeclaration processorDeclaration;
private StAXArtifactProcessor processor;
private Class modelType;
LazyStAXArtifactProcessor(ModelFactoryExtensionPoint modelFactories,
QName artifactType,
String modelTypeName,
String factoryName,
ServiceDeclaration processorDeclaration) {
this.modelFactories = modelFactories;
this.artifactType = artifactType;
this.modelTypeName = modelTypeName;
this.factoryName = factoryName;
this.processorDeclaration = processorDeclaration;
}
public QName getArtifactType() {
return artifactType;
}
@SuppressWarnings("unchecked")
private StAXArtifactProcessor getProcessor() {
if (processor == null) {
if (processorDeclaration.getClassName()
.equals("org.apache.tuscany.sca.assembly.xml.DefaultBeanModelProcessor")) {
// Specific initialization for the DefaultBeanModelProcessor
AssemblyFactory assemblyFactory = modelFactories.getFactory(AssemblyFactory.class);
PolicyFactory policyFactory = modelFactories.getFactory(PolicyFactory.class);
try {
Class<StAXArtifactProcessor> processorClass =
(Class<StAXArtifactProcessor>)processorDeclaration.loadClass();
Object modelFactory;
if (factoryName != null) {
Class<?> factoryClass = (Class<?>)processorDeclaration.loadClass(factoryName);
modelFactory = modelFactories.getFactory(factoryClass);
} else {
modelFactory = null;
}
Constructor<StAXArtifactProcessor> constructor =
processorClass.getConstructor(AssemblyFactory.class,
PolicyFactory.class,
QName.class,
Class.class,
Object.class);
processor =
constructor.newInstance(assemblyFactory,
policyFactory,
artifactType,
getModelType(),
modelFactory);
} catch (Exception e) {
throw new IllegalStateException(e);
}
} else {
// Load and instanciate the processor class
try {
Class<StAXArtifactProcessor> processorClass =
(Class<StAXArtifactProcessor>)processorDeclaration.loadClass();
Constructor<StAXArtifactProcessor> constructor =
processorClass.getConstructor(ModelFactoryExtensionPoint.class);
processor = constructor.newInstance(modelFactories);
} catch (Exception e) {
throw new IllegalStateException(e);
}
}
}
return processor;
}
public Object read(XMLStreamReader inputSource) throws ContributionReadException, XMLStreamException {
return getProcessor().read(inputSource);
}
@SuppressWarnings("unchecked")
public void write(Object model, XMLStreamWriter outputSource) throws ContributionWriteException,
XMLStreamException {
getProcessor().write(model, outputSource);
}
public Class getModelType() {
if (modelType == null) {
try {
modelType = processorDeclaration.loadClass(modelTypeName);
} catch (Exception e) {
throw new IllegalStateException(e);
}
}
return modelType;
}
@SuppressWarnings("unchecked")
public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
getProcessor().resolve(model, resolver);
}
}
}