/**
* 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.metamodel.data;
/**
* Wraps another DataSet and enforces a maximum number of rows constraint
*/
public final class MaxRowsDataSet extends AbstractDataSet implements WrappingDataSet {
private final DataSet _dataSet;
private volatile int _rowsLeft;
public MaxRowsDataSet(DataSet dataSet, int maxRows) {
super(dataSet);
_dataSet = dataSet;
_rowsLeft = maxRows;
}
@Override
public DataSet getWrappedDataSet() {
return _dataSet;
}
@Override
public void close() {
_dataSet.close();
}
@Override
public Row getRow() {
return _dataSet.getRow();
}
@Override
public boolean next() {
if (_rowsLeft > 0) {
boolean next = _dataSet.next();
if (next) {
_rowsLeft--;
}
return next;
}
return false;
}
}