/*
* Copyright 2002-2011 the original author or authors.
*
* 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.springframework.jdbc.core;
import java.lang.reflect.Method;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.rowset.CachedRowSet;
import com.sun.rowset.CachedRowSetImpl;
import org.springframework.jdbc.support.rowset.ResultSetWrappingSqlRowSet;
import org.springframework.jdbc.support.rowset.SqlRowSet;
import org.springframework.util.ReflectionUtils;
/**
* ResultSetExtractor implementation that returns a Spring SqlRowSet
* representation for each given ResultSet.
*
* <p>The default implementation uses a standard JDBC CachedRowSet underneath.
* This means that JDBC RowSet support needs to be available at runtime:
* by default, Sun's <code>com.sun.rowset.CachedRowSetImpl</code> class on Java 5 and 6,
* or the <code>javax.sql.rowset.RowSetProvider</code> mechanism on Java 7 / JDBC 4.1.
*
* @author Juergen Hoeller
* @since 1.2
* @see #newCachedRowSet
* @see org.springframework.jdbc.support.rowset.SqlRowSet
* @see JdbcTemplate#queryForRowSet(String)
* @see javax.sql.rowset.CachedRowSet
*/
public class SqlRowSetResultSetExtractor implements ResultSetExtractor<SqlRowSet> {
private static Object rowSetFactory = null;
private static Method createCachedRowSet = null;
static {
ClassLoader cl = SqlRowSetResultSetExtractor.class.getClassLoader();
try {
Class rowSetProviderClass = cl.loadClass("javax.sql.rowset.RowSetProvider");
Method newFactory = rowSetProviderClass.getMethod("newFactory");
rowSetFactory = ReflectionUtils.invokeMethod(newFactory, null);
createCachedRowSet = rowSetFactory.getClass().getMethod("createCachedRowSet");
}
catch (Exception ex) {
// JDBC 4.1 API not available - fall back to Sun CachedRowSetImpl
}
}
public SqlRowSet extractData(ResultSet rs) throws SQLException {
return createSqlRowSet(rs);
}
/**
* Create a SqlRowSet that wraps the given ResultSet,
* representing its data in a disconnected fashion.
* <p>This implementation creates a Spring ResultSetWrappingSqlRowSet
* instance that wraps a standard JDBC CachedRowSet instance.
* Can be overridden to use a different implementation.
* @param rs the original ResultSet (connected)
* @return the disconnected SqlRowSet
* @throws SQLException if thrown by JDBC methods
* @see #newCachedRowSet
* @see org.springframework.jdbc.support.rowset.ResultSetWrappingSqlRowSet
*/
protected SqlRowSet createSqlRowSet(ResultSet rs) throws SQLException {
CachedRowSet rowSet = newCachedRowSet();
rowSet.populate(rs);
return new ResultSetWrappingSqlRowSet(rowSet);
}
/**
* Create a new CachedRowSet instance, to be populated by
* the <code>createSqlRowSet</code> implementation.
* <p>The default implementation creates a new instance of
* Sun's <code>com.sun.rowset.CachedRowSetImpl</code> class.
* @return a new CachedRowSet instance
* @throws SQLException if thrown by JDBC methods
* @see #createSqlRowSet
* @see com.sun.rowset.CachedRowSetImpl
*/
protected CachedRowSet newCachedRowSet() throws SQLException {
if (createCachedRowSet != null) {
// RowSetProvider.newFactory().createCachedRowSet();
return (CachedRowSet) ReflectionUtils.invokeJdbcMethod(createCachedRowSet, rowSetFactory);
}
else {
return new CachedRowSetImpl();
}
}
}