/*
* Licensed to Crate under one or more contributor license agreements.
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership. Crate 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial
* agreement.
*/
package io.crate.data;
/**
* Columns implementation that is backed by a underlying {@link Row} instance.
*
* The Row instance pointer can be changed using {@link #updateRef(Row)}
*/
public class RowColumns implements Columns {
private final int numColumns;
private final ProxyInput[] inputs;
private Row currentRow = RowBridging.OFF_ROW;
public RowColumns(int numColumns) {
this.numColumns = numColumns;
this.inputs = new ProxyInput[numColumns];
for (int i = 0; i < numColumns; i++) {
inputs[i] = new ProxyInput(i);
}
}
@Override
public Input<?> get(int index) {
return inputs[index];
}
@Override
public int size() {
return numColumns;
}
public void updateRef(Row row) {
currentRow = row;
}
private class ProxyInput implements Input<Object> {
private final int columnIdx;
ProxyInput(int columnIdx) {
this.columnIdx = columnIdx;
}
@Override
public Object value() {
return currentRow.get(columnIdx);
}
}
}