/* Licensed 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.activiti.engine.query;
import java.util.List;
import org.activiti.engine.ActivitiException;
/**
* Describes basic methods for doing native queries
*
* @author Bernd Ruecker (camunda)
*/
public interface NativeQuery<T extends NativeQuery< ? , ? >, U extends Object> {
/**
* Hand in the SQL statement you want to execute. BEWARE: if you need a count you have to hand in a count() statement
* yourself, otherwise the result will be treated as lost of Activiti entities.
*
* If you need paging you have to insert the pagination code yourself. We skipped doing this for you
* as this is done really different on some databases (especially MS-SQL / DB2)
*/
T sql(String selectClause);
/**
* Add parameter to be replaced in query for index, e.g. :param1, :myParam, ...
*/
T parameter(String name, Object value);
/** Executes the query and returns the number of results */
long count();
/**
* Executes the query and returns the resulting entity or null if no
* entity matches the query criteria.
* @throws ActivitiException when the query results in more than one
* entities.
*/
U singleResult();
/** Executes the query and get a list of entities as the result. */
List<U> list();
}