content: /*
   * Copyright © 2018-2025 Commonwealth Scientific and Industrial Research
   * Organisation (CSIRO) ABN 41 687 119 230.
   *
   * 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 au.csiro.pathling.sql.udf;
  
  import org.apache.spark.sql.types.DataType;
  
  /**
   * The interface that encapsulates meta data required for registration of a custom UDF function in
   * Spark.
   */
  public interface SqlFunction {
  
    /**
     * Gets the name of the UDF.
     *
     * @return the name of the UDF function.
     */
    String getName();
  
    /**
     * Gets the return type of the UDF
     *
     * @return the SQL type returned by the UDF.
     */
    DataType getReturnType();
  
  }
  