/*
* 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.resolver.impl;
import java.lang.ref.WeakReference;
import java.lang.reflect.Constructor;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import org.apache.tuscany.sca.contribution.Contribution;
import org.apache.tuscany.sca.contribution.ModelFactoryExtensionPoint;
import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
import org.apache.tuscany.sca.contribution.resolver.ResourceReference;
/**
* A Model Resolver for ResourceReferences.
*
*/
public class ResourceReferenceModelResolver implements ModelResolver {
private Contribution contribution;
protected WeakReference<ClassLoader> classLoader;
private Map<String, ResourceReference> map = new HashMap<String, ResourceReference>();
private ModelResolver osgiResolver;
public ResourceReferenceModelResolver(Contribution contribution, ModelFactoryExtensionPoint modelFactories) {
this.contribution = contribution;
this.classLoader = new WeakReference<ClassLoader>(this.contribution.getClassLoader());
try {
Class osgiResolverClass =
Class.forName("org.apache.tuscany.sca.contribution.osgi.impl.OSGiResourceReferenceModelResolver");
if (osgiResolverClass != null) {
Constructor constructor =
osgiResolverClass.getConstructor(Contribution.class, ModelFactoryExtensionPoint.class);
this.osgiResolver = (ModelResolver)constructor.newInstance(contribution, modelFactories);
}
} catch (Exception e) {
}
}
public void addModel(Object resolved) {
ResourceReference resourceRef = (ResourceReference)resolved;
map.put(resourceRef.getResourceName(), resourceRef);
}
public Object removeModel(Object resolved) {
return map.remove(((ResourceReference)resolved).getResourceName());
}
public <T> T resolveModel(Class<T> modelClass, T unresolved) {
Object resolved = map.get(unresolved);
if (resolved != null) {
return modelClass.cast(resolved);
}
//Get a resource
String resourceName = ((ResourceReference)unresolved).getResourceName();
URL resourceURL = null;
if (URI.create(resourceName).isAbsolute()) {
try {
resourceURL = URI.create(resourceName).toURL();
} catch (MalformedURLException e) {
// Ignore
}
}
if (resourceURL == null && osgiResolver != null) {
// Try OSGi
resolved = osgiResolver.resolveModel(modelClass, unresolved);
resourceURL = ((ResourceReference)resolved).getResource();
}
if (resourceURL == null) {
// Try class loader
resourceURL = classLoader.get().getResource(resourceName);
}
if (resourceURL != null) {
// Store a new ResourceReference wrappering the resource
ResourceReference resourceReference = new ResourceReference(resourceName, resourceURL);
map.put(resourceName, resourceReference);
// Return the resolved ResourceReference
return modelClass.cast(resourceReference);
} else {
return unresolved;
}
}
}