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.impl.parser;
  
  import static org.apache.beam.sdk.extensions.sql.impl.parser.SqlDdlNodes.name;
  import static org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.util.Static.RESOURCE;
  
  import org.apache.beam.sdk.extensions.sql.impl.BeamCalciteSchema;
  import org.apache.beam.sdk.extensions.sql.impl.CatalogManagerSchema;
  import org.apache.beam.sdk.extensions.sql.impl.CatalogSchema;
  import org.apache.beam.sdk.extensions.sql.impl.TableName;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.jdbc.CalcitePrepare;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.jdbc.CalciteSchema;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.schema.Schema;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.SqlIdentifier;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.SqlKind;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.SqlOperator;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.SqlSpecialOperator;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.SqlUtil;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.sql.parser.SqlParserPos;
  import org.apache.beam.vendor.calcite.v1_40_0.org.apache.calcite.util.Pair;
  
  /** Parse tree for {@code DROP TABLE} statement. */
  public class SqlDropTable extends SqlDropObject {
    private static final SqlOperator OPERATOR =
        new SqlSpecialOperator("DROP TABLE", SqlKind.DROP_TABLE);
  
    /** Creates a SqlDropTable. */
    SqlDropTable(SqlParserPos pos, boolean ifExists, SqlIdentifier name) {
      super(OPERATOR, pos, ifExists, name);
    }
  
    @Override
    public void execute(CalcitePrepare.Context context) {
      final Pair<CalciteSchema, String> pair = SqlDdlNodes.schema(context, true, name);
      TableName pathOverride = TableName.create(name.toString());
      Schema schema = pair.left.schema;
  
      BeamCalciteSchema beamCalciteSchema;
      if (schema instanceof CatalogManagerSchema) {
        CatalogSchema catalogSchema = ((CatalogManagerSchema) schema).getCatalogSchema(pathOverride);
        beamCalciteSchema = catalogSchema.getDatabaseSchema(pathOverride);
      } else if (schema instanceof BeamCalciteSchema) {
        beamCalciteSchema = (BeamCalciteSchema) schema;
      } else {
        throw SqlUtil.newContextException(
            name.getParserPosition(),
            RESOURCE.internal(
                "Attempting to drop a table using unexpected Calcite Schema of type "
                    + schema.getClass()));
      }
  
      if (beamCalciteSchema.getTable(pair.right) == null) {
        // Table does not exist.
        if (!ifExists) {
          // They did not specify IF EXISTS, so give error.
          throw SqlUtil.newContextException(
              name.getParserPosition(), RESOURCE.tableNotFound(name.toString()));
        }
        return;
      }
  
      beamCalciteSchema.getTableProvider().dropTable(pair.right);
    }
  }
  
  // End SqlDropTable.java
  