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* 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.cayenne.access.jdbc;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.util.Map;
import org.apache.commons.collections.ExtendedProperties;
import org.apache.commons.collections.map.LRUMap;
import org.apache.velocity.Template;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.runtime.resource.ResourceManager;
import org.apache.velocity.runtime.resource.loader.ResourceLoader;
/**
* An implementation of the Velocity ResourceManager and ResourceLoader that
* creates templates from in-memory Strings.
*
* @since 1.1
*/
// class must be public since it is instantiated by Velocity via reflection.
public class SQLTemplateResourceManager
extends ResourceLoader
implements ResourceManager {
protected Map<String, Template> templateCache;
public void initialize(RuntimeServices rs) throws Exception {
super.rsvc = rs;
this.templateCache = new LRUMap(100);
}
public void clearCache() {
templateCache.clear();
}
/**
* Returns a Velocity Resource which is a Template for the given SQL.
*/
public Resource getResource(String resourceName, int resourceType, String encoding)
throws ResourceNotFoundException, ParseErrorException, Exception {
synchronized (templateCache) {
Template resource = templateCache.get(resourceName);
if (resource == null) {
resource = new Template();
resource.setRuntimeServices(rsvc);
resource.setResourceLoader(this);
resource.setName(resourceName);
resource.setEncoding(encoding);
resource.process();
templateCache.put(resourceName, resource);
}
return resource;
}
}
public String getLoaderNameForResource(String resourceName) {
return getClass().getName();
}
@Override
public long getLastModified(Resource resource) {
return -1;
}
@Override
public InputStream getResourceStream(String source)
throws ResourceNotFoundException {
return new ByteArrayInputStream(source.getBytes());
}
@Override
public void init(ExtendedProperties configuration) {
}
@Override
public boolean isSourceModified(Resource resource) {
return false;
}
}