/*
* 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.deltaspike.data.impl.util.jpa;
import javax.persistence.Query;
public class QueryStringExtractorFactory
{
private final QueryStringExtractor[] extractors = new QueryStringExtractor[]
{
new HibernateQueryStringExtractor(),
new EclipseLinkEjbQueryStringExtractor(),
new OpenJpaQueryStringExtractor()
};
public String extract(final Query query)
{
for (final QueryStringExtractor extractor : extractors)
{
final String compare = extractor.getClass().getAnnotation(ProviderSpecific.class).value();
final Object implQuery = toImplQuery(compare, query);
if (implQuery != null)
{
return extractor.extractFrom(implQuery);
}
}
throw new RuntimeException("Persistence provider not supported");
}
private static Object toImplQuery(final String clazzName, final Query query)
{
try
{
Class<?> toClass = Class.forName(clazzName);
try
{
// throw a persistence exception if not possible
return query.unwrap(toClass);
}
catch (Exception e)
{
toClass.cast(query);
return query;
}
}
catch (Exception e)
{
return null;
}
}
}