sdks/java/extensions/sql/src/main/java/org/apache/beam/sdk/extensions/sql/impl/cep/CEPKind.java

/*
 * 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.beam.sdk.extensions.sql.impl.cep;

import java.io.Serializable;

/**
 * {@code CEPKind} corresponds to Calcite's {@code SqlKind}. It records some special SQL operations.
 */
public enum CEPKind implements Serializable {
  COUNT,
  AVG,
  SUM,
  FIRST,
  LAST,
  PREV,
  NEXT,
  EQUALS,
  GREATER_THAN,
  GREATER_THAN_OR_EQUAL,
  LESS_THAN,
  LESS_THAN_OR_EQUAL,
  NONE
}