/**
* Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
*
* 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 com.linkedin.pinot.core.operator.filter;
import com.linkedin.pinot.core.common.Block;
import com.linkedin.pinot.core.common.BlockId;
import com.linkedin.pinot.core.operator.BaseOperator;
import com.linkedin.pinot.core.operator.blocks.BaseFilterBlock;
/**
* Base Operator for all filter operators. ResultBlock is initialized in the planning phase
*
*/
public abstract class BaseFilterOperator extends BaseOperator {
private int nextBlockCallCounter = 0;
@Override
public final BaseFilterBlock getNextBlock() {
return getNextBlock(new BlockId(0));
}
@Override
public final BaseFilterBlock getNextBlock(BlockId blockId) {
if (nextBlockCallCounter > 0) {
return null;
}
Block nextBlock = nextFilterBlock(new BlockId(0));
nextBlockCallCounter = nextBlockCallCounter + 1;
return (BaseFilterBlock) nextBlock;
}
public abstract BaseFilterBlock nextFilterBlock(BlockId blockId);
public abstract boolean isResultEmpty();
}