/*
* Copyright (C) 2008-2015 by Holger Arndt
*
* This file is part of the Universal Java Matrix Package (UJMP).
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership and licensing.
*
* UJMP is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* UJMP is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with UJMP; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
package org.ujmp.jdbc.util;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Iterator;
public class JDBCKeyIterator<K> implements Iterator<K> {
private final ResultSet rs;
private final Class<?> keyClass;
private K currentKey = null;
@SuppressWarnings("unchecked")
public JDBCKeyIterator(ResultSet rs, Class<?> keyClass) {
this.rs = rs;
this.keyClass = keyClass;
try {
if (rs.next()) {
currentKey = (K) SQLUtil.getObject(rs, 1, keyClass);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public boolean hasNext() {
return currentKey != null;
}
@SuppressWarnings("unchecked")
public K next() {
try {
K lastKey = currentKey;
if (rs.next()) {
currentKey = (K) SQLUtil.getObject(rs, 1, keyClass);
} else {
currentKey = null;
}
return lastKey;
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public void remove() {
throw new UnsupportedOperationException();
}
}