/**
* 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 transparently applies a set of filters to it.
*/
public final class FilteredDataSet extends AbstractDataSet implements WrappingDataSet {
private final DataSet _dataSet;
private final IRowFilter[] _filters;
private Row _row;
public FilteredDataSet(DataSet dataSet, IRowFilter... filters) {
super(dataSet);
_dataSet = dataSet;
_filters = filters;
}
@Override
public void close() {
super.close();
_dataSet.close();
}
@Override
public DataSet getWrappedDataSet() {
return _dataSet;
}
@Override
public boolean next() {
boolean next = false;
while (_dataSet.next()) {
Row row = _dataSet.getRow();
for (IRowFilter filter : _filters) {
next = filter.accept(row);
if (!next) {
break;
}
}
if (next) {
_row = row;
break;
}
}
return next;
}
@Override
public Row getRow() {
return _row;
}
}