SqlWithItemTableRef.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.calcite.sql.validate;

import org.apache.calcite.sql.SqlCall;
import org.apache.calcite.sql.SqlKind;
import org.apache.calcite.sql.SqlLiteral;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.SqlNodeList;
import org.apache.calcite.sql.SqlOperator;
import org.apache.calcite.sql.SqlSpecialOperator;
import org.apache.calcite.sql.SqlTableRef;
import org.apache.calcite.sql.SqlWithItem;
import org.apache.calcite.sql.parser.SqlParserPos;

import org.checkerframework.checker.nullness.qual.Nullable;

import static java.util.Objects.requireNonNull;

/**
 * A <code>SqlWithItemTableRef</code> is a node created during validation for
 * recursive queries which represents a table reference in a {@code WITH RECURSIVE} clause.
 */
public class SqlWithItemTableRef extends SqlTableRef {
  private final SqlWithItem withItem;
  public SqlWithItemTableRef(SqlParserPos pos,
      SqlWithItem withItem) {
    super(pos, withItem.name, SqlNodeList.EMPTY);
    this.withItem = withItem;
  }

  private static final SqlOperator OPERATOR =
      new SqlSpecialOperator("WITH_ITEM_TABLE_REF", SqlKind.WITH_ITEM_TABLE_REF) {
        @Override public SqlCall createCall(
            @Nullable SqlLiteral functionQualifier,
            SqlParserPos pos, @Nullable SqlNode... operands) {
          return new SqlWithItemTableRef(pos,
              (SqlWithItem) requireNonNull(operands[0], "withItem"));
        }
      };
  @Override public SqlOperator getOperator() {
    return OPERATOR;
  }

  public SqlWithItem getWithItem() {
    return withItem;
  }
}