org.springframework.jdbc.core.SqlRowSetResultSetExtractor Maven / Gradle / Ivy
/*
* Copyright 2002-2014 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.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.rowset.CachedRowSet;
import javax.sql.rowset.RowSetFactory;
import javax.sql.rowset.RowSetProvider;
import org.springframework.core.JdkVersion;
import org.springframework.jdbc.support.rowset.ResultSetWrappingSqlRowSet;
import org.springframework.jdbc.support.rowset.SqlRowSet;
import org.springframework.util.ClassUtils;
/**
* {@link ResultSetExtractor} implementation that returns a Spring {@link SqlRowSet}
* representation for each given {@link ResultSet}.
*
* 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} class on Java 5 and 6,
* or the {@code javax.sql.rowset.RowSetProvider} 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 {
private static final CachedRowSetFactory cachedRowSetFactory;
static {
if (JdkVersion.getMajorJavaVersion() >= JdkVersion.JAVA_17) {
// using JDBC 4.1 RowSetProvider
cachedRowSetFactory = new StandardCachedRowSetFactory();
}
else {
// JDBC 4.1 API not available - fall back to Sun CachedRowSetImpl
cachedRowSetFactory = new SunCachedRowSetFactory();
}
}
@Override
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.
* 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} implementation.
*
The default implementation uses JDBC 4.1's RowSetProvider
* when running on JDK 7 or higher, falling back to Sun's
* {@code com.sun.rowset.CachedRowSetImpl} class on older JDKs.
* @return a new CachedRowSet instance
* @throws SQLException if thrown by JDBC methods
* @see #createSqlRowSet
*/
protected CachedRowSet newCachedRowSet() throws SQLException {
return cachedRowSetFactory.createCachedRowSet();
}
/**
* Internal strategy interface for the creation of CachedRowSet instances.
*/
private interface CachedRowSetFactory {
CachedRowSet createCachedRowSet() throws SQLException;
}
/**
* Inner class to avoid a hard dependency on JDBC 4.1 RowSetProvider class.
*/
private static class StandardCachedRowSetFactory implements CachedRowSetFactory {
private final RowSetFactory rowSetFactory;
public StandardCachedRowSetFactory() {
try {
this.rowSetFactory = RowSetProvider.newFactory();
}
catch (SQLException ex) {
throw new IllegalStateException("Cannot create RowSetFactory through RowSetProvider", ex);
}
}
@Override
public CachedRowSet createCachedRowSet() throws SQLException {
return this.rowSetFactory.createCachedRowSet();
}
}
/**
* Inner class to avoid a hard dependency on Sun's CachedRowSetImpl class.
*/
private static class SunCachedRowSetFactory implements CachedRowSetFactory {
private static final Class implementationClass;
static {
try {
implementationClass = ClassUtils.forName("com.sun.rowset.CachedRowSetImpl",
SqlRowSetResultSetExtractor.class.getClassLoader());
}
catch (Throwable ex) {
throw new IllegalStateException(ex);
}
}
@Override
public CachedRowSet createCachedRowSet() throws SQLException {
try {
return (CachedRowSet) implementationClass.newInstance();
}
catch (Throwable ex) {
throw new IllegalStateException(ex);
}
}
}
}