/*
 * Copyright 2018 Confluent Inc.
 *
 * Licensed under the Confluent Community License (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.confluent.io/confluent-community-license
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OF ANY KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations under the License.
 */

package io.confluent.ksql.function.udaf.placeholder;

import io.confluent.ksql.function.udaf.TableUdaf;

/**
 * A no-op {@link TableUdaf} that is used as a placeholder for some later hardcoded computation.
 */
public final class PlaceholderTableUdaf implements TableUdaf<Long, Long> {

  public static final PlaceholderTableUdaf INSTANCE = new PlaceholderTableUdaf();

  private PlaceholderTableUdaf() {
  }

  @Override
  public Long undo(final Long valueToUndo, final Long aggregateValue) {
    return null;
  }

  @Override
  public Long initialize() {
    return null;
  }

  @Override
  public Long aggregate(final Long value, final Long aggregate) {
    return null;
  }

  @Override
  public Long merge(final Long aggOne, final Long aggTwo) {
    return null;
  }
}
