content: /*
   * 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;
  
  import java.io.Serializable;
  import java.util.List;
  import org.apache.beam.sdk.options.PipelineOptions;
  import org.apache.beam.sdk.schemas.Schema;
  import org.apache.beam.sdk.transforms.DoFn;
  import org.apache.beam.sdk.values.Row;
  
  /**
   * A seekable table converts a JOIN operator to an inline lookup. It's triggered by {@code SELECT *
   * FROM FACT_TABLE JOIN LOOKUP_TABLE ON ...}.
   */
  public interface BeamSqlSeekableTable extends Serializable {
    /**
     * prepare the instance.
     *
     * @param joinSubsetType joining subset schema
     */
    default void setUp(Schema joinSubsetType) {}
  
    default void startBundle(
        DoFn<Row, Row>.StartBundleContext context, PipelineOptions pipelineOptions) {}
  
    default void finishBundle(
        DoFn<Row, Row>.FinishBundleContext context, PipelineOptions pipelineOptions) {}
  
    /** return a list of {@code Row} with given key set. */
    List<Row> seekRow(Row lookupSubRow);
  
    /** cleanup resources of the instance. */
    default void tearDown() {}
  }
  