/**
* 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.jena.jdbc.results;
import java.sql.SQLException;
import org.apache.jena.jdbc.statements.JenaStatement;
import org.apache.jena.query.QueryExecution ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Abstract base class for result sets that are backed by a {@link QueryExecution}
*
*/
public abstract class QueryExecutionResults extends JenaResultSet {
private static final Logger LOGGER = LoggerFactory.getLogger(QueryExecutionResults.class);
private QueryExecution qe;
private boolean commit = false;
/**
* Creates new Query Execution backed results
* @param statement Statement
* @param qe Query Execution
* @param commit Whether a commit is needed when the results are closed
* @throws SQLException Thrown if there is an issue creating the results
*/
public QueryExecutionResults(JenaStatement statement, QueryExecution qe, boolean commit) throws SQLException {
super(statement);
if (qe == null) throw new SQLException("Query Execution cannot be null");
this.qe = qe;
this.commit = commit;
}
/**
* Closes the results which also closes the underlying {@link QueryExecution}
*/
@Override
public final void close() throws SQLException {
if (this.qe != null) {
try {
// Close the query execution
this.qe.close();
} catch (Exception e) {
LOGGER.error("Unexpected error closing underlying Jena query execution", e);
throw new SQLException("Unexpected error closing the query execution", e);
} finally {
this.qe = null;
// Commit if necessary
if (this.commit) {
LOGGER.info("Result Set associated with an auto-committing transaction, performing a commit now");
this.getStatement().getConnection().commit();
}
}
}
this.closeInternal();
}
/**
* Method which derived classes must implement to provide their own close logic
* @throws SQLException Thrown if there is an issue closing the results
*/
protected abstract void closeInternal() throws SQLException;
@Override
public final boolean isClosed() {
return this.qe == null;
}
}