/**
 * 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 com.datatorrent.lib.streamquery.index;

import java.util.Map;

import javax.validation.constraints.NotNull;

/**
 * Interface to define sql select statement indexes for column names,aggregate.
 * <p>
 * @displayName Index
 * @category Stream Manipulators
 * @tags index
 * @since 0.3.2
 */
public interface Index
{
  /**
   * Function can key/value hash map, does metric implemented by sub class.
   */
  public void filter(@NotNull Map<String, Object> row, @NotNull Map<String, Object> collect);
}