/*
* 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.implementation.spring.xml;
import static javax.xml.stream.XMLStreamConstants.END_ELEMENT;
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.assembly.ComponentType;
import org.apache.tuscany.sca.assembly.xml.Constants;
import org.apache.tuscany.sca.assembly.xml.PolicySubjectProcessor;
import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
import org.apache.tuscany.sca.contribution.processor.ContributionResolveException;
import org.apache.tuscany.sca.contribution.processor.ContributionWriteException;
import org.apache.tuscany.sca.contribution.processor.ProcessorContext;
import org.apache.tuscany.sca.contribution.processor.StAXArtifactProcessor;
import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
import org.apache.tuscany.sca.core.ExtensionPointRegistry;
import org.apache.tuscany.sca.core.FactoryExtensionPoint;
import org.apache.tuscany.sca.implementation.spring.SpringImplementation;
import org.apache.tuscany.sca.implementation.spring.introspect.SpringXMLComponentTypeLoader;
import org.apache.tuscany.sca.monitor.Monitor;
import org.apache.tuscany.sca.monitor.Problem;
import org.apache.tuscany.sca.monitor.Problem.Severity;
/**
* SpringArtifactProcessor is responsible for processing the XML of an <implementation.spring.../>
* element in an SCA SCDL file.
*
* @version $Rev: 826907 $ $Date: 2009-10-20 00:17:14 +0000 (Tue, 20 Oct 2009) $
*/
public class SpringImplementationProcessor implements StAXArtifactProcessor<SpringImplementation> {
private static final String LOCATION = "location";
private static final String IMPLEMENTATION_SPRING = "implementation.spring";
private static final QName IMPLEMENTATION_SPRING_QNAME = new QName(Constants.SCA11_NS, IMPLEMENTATION_SPRING);
private static final String MSG_LOCATION_MISSING = "Reading implementation.spring - location attribute missing";
private ExtensionPointRegistry registry;
private AssemblyFactory assemblyFactory;
private PolicySubjectProcessor policyProcessor;
private FactoryExtensionPoint factories;
public SpringImplementationProcessor(ExtensionPointRegistry registry) {
this.registry = registry;
this.factories = registry.getExtensionPoint(FactoryExtensionPoint.class);
this.assemblyFactory = factories.getFactory(AssemblyFactory.class);
this.policyProcessor = new PolicySubjectProcessor(registry);
}
/**
* Report a exception.
*
* @param problems
* @param message
* @param model
*/
private void error(Monitor monitor, String message, Object model, Exception ex) {
if (monitor != null) {
Problem problem = monitor.createProblem(this.getClass().getName(), "impl-spring-validation-messages", Severity.ERROR, model, message, ex);
monitor.problem(problem);
}
}
/**
* Report a error.
*
* @param problems
* @param message
* @param model
*/
private void error(Monitor monitor, String message, Object model, Object... messageParameters) {
if (monitor != null) {
Problem problem = monitor.createProblem(this.getClass().getName(), "impl-spring-validation-messages", Severity.ERROR, model, message, (Object[])messageParameters);
monitor.problem(problem);
}
}
/*
* Read the XML and parse out the attributes.
*
* <implementation.spring.../> has a single required attribute:
* "location" - which is the target URI of of an archive file or a directory that contains the Spring
* application context files.
* If the resource identified by the location attribute is an archive file, then the file
* META-INF/MANIFEST.MF is read from the archive.
* If the location URI identifies a directory, then META-INF/MANIFEST.MF must exist
* underneath that directory.
* If the manifest file contains a header "Spring-Context" of the format:
* Spring-Context ::= path ( ';' path )*
*
* Where path is a relative path with respect to the location URI, then the set of paths
* specified in the header identify the context configuration files.
* If there is no MANIFEST.MF file or no Spring-Context header within that file,
* then the default behaviour is to build an application context using all the *.xml files
* in the METAINF/spring directory.
*/
public SpringImplementation read(XMLStreamReader reader, ProcessorContext context) throws ContributionReadException, XMLStreamException {
// Create the Spring implementation
SpringImplementation springImplementation = null;
// Read the location attribute for the spring implementation
String springLocation = reader.getAttributeValue(null, LOCATION);
if (springLocation != null) {
springImplementation = new SpringImplementation();
springImplementation.setLocation(springLocation);
springImplementation.setUnresolved(true);
processComponentType(springImplementation);
} else {
error(context.getMonitor(), "LocationAttributeMissing", reader);
//throw new ContributionReadException(MSG_LOCATION_MISSING);
}
// Read policies
policyProcessor.readPolicies(springImplementation, reader);
// Skip to end element
while (reader.hasNext()) {
if (reader.next() == END_ELEMENT && IMPLEMENTATION_SPRING_QNAME.equals(reader.getName())) {
break;
}
} // end while
return springImplementation;
} // end read
/*
* Handles the component type for the Spring implementation
* @param springImplementation - a Spring implementation. The component type information
* is created for this implementation
*
*/
private void processComponentType(SpringImplementation springImplementation) {
// Create a ComponentType and mark it unresolved
ComponentType componentType = assemblyFactory.createComponentType();
componentType.setUnresolved(true);
springImplementation.setComponentType(componentType);
} // end processComponentType
/*
* Write out the XML representation of the Spring implementation
* <implementation.spring location="..." />
*/
public void write(SpringImplementation springImplementation, XMLStreamWriter writer, ProcessorContext context) throws ContributionWriteException, XMLStreamException {
// Write <implementation.spring>
writer.writeStartElement(Constants.SCA11_NS, IMPLEMENTATION_SPRING);
policyProcessor.writePolicyAttributes(springImplementation, writer);
if (springImplementation.getLocation() != null) {
writer.writeAttribute(LOCATION, springImplementation.getLocation());
}
writer.writeEndElement();
} // end write
/**
* Resolves the Spring implementation - loads the Spring application-context XML and
* derives the spring implementation componentType from it
*/
public void resolve(SpringImplementation springImplementation, ModelResolver resolver, ProcessorContext context)
throws ContributionResolveException {
if (springImplementation == null)
return;
Monitor monitor = context.getMonitor();
/* Load the Spring component type by reading the Spring application context */
SpringXMLComponentTypeLoader springLoader =
new SpringXMLComponentTypeLoader(registry, monitor);
try {
// Load the Spring Implementation information from its application context file...
springLoader.load(springImplementation, resolver, context);
} catch (ContributionReadException e) {
ContributionResolveException ce = new ContributionResolveException(e);
error(monitor, "ContributionResolveException", resolver, ce);
throw ce;
}
ComponentType ct = springImplementation.getComponentType();
if (ct.isUnresolved()) {
// If the introspection fails to resolve, try to find a side file...
ComponentType componentType = resolver.resolveModel(ComponentType.class, ct, context);
if (componentType.isUnresolved()) {
error(monitor, "UnableToResolveComponentType", resolver);
//throw new ContributionResolveException("SpringArtifactProcessor: unable to resolve componentType for Spring component");
} else {
springImplementation.setComponentType(componentType);
springImplementation.setUnresolved(false);
}
} // end if
} // end method resolve
public QName getArtifactType() {
return IMPLEMENTATION_SPRING_QNAME;
}
public Class<SpringImplementation> getModelType() {
return SpringImplementation.class;
}
} // end class SpringArtifactProcessor
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