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.calcite.sql.babel.postgres;
  
  import org.apache.calcite.sql.SqlCall;
  import org.apache.calcite.sql.SqlNode;
  import org.apache.calcite.sql.SqlNodeList;
  import org.apache.calcite.sql.SqlOperator;
  import org.apache.calcite.sql.SqlWriter;
  import org.apache.calcite.sql.fun.SqlBasicOperator;
  import org.apache.calcite.sql.parser.SqlParserPos;
  
  import com.google.common.collect.ImmutableList;
  
  import java.util.List;
  
  /**
   * Parse tree node representing a {@code BEGIN} clause.
   *
   * @see <a href="https://www.postgresql.org/docs/current/sql-begin.html">BEGIN specification</a>
   */
  public class SqlBegin extends SqlCall {
    public static final SqlBasicOperator OPERATOR =
        SqlBasicOperator.create("BEGIN").withCallFactory(
            (operator, functionQualifier, pos, operands) ->
                new SqlBegin(pos, (SqlNodeList) operands[0]));
  
    private final SqlNodeList transactionModeList;
  
    protected SqlBegin(final SqlParserPos pos, final SqlNodeList transactionModeList) {
      super(pos);
      this.transactionModeList = transactionModeList;
    }
  
    @Override public SqlOperator getOperator() {
      return OPERATOR;
    }
  
    @Override public List<SqlNode> getOperandList() {
      return ImmutableList.of(transactionModeList);
    }
  
    @Override public void unparse(final SqlWriter writer, final int leftPrec, final int rightPrec) {
      writer.keyword("BEGIN");
      transactionModeList.unparse(writer, -1, -1);
    }
  }
  