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.rel.type;
  
  import org.apache.calcite.sql.type.SqlTypeName;
  import org.apache.calcite.util.Pair;
  import org.apache.calcite.util.Util;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Holding the expandable list of fields for dynamic table.
   */
  class RelDataTypeHolder {
    private final List<RelDataTypeField> fields = new ArrayList<>();
    private final RelDataTypeFactory typeFactory;
  
    RelDataTypeHolder(RelDataTypeFactory typeFactory) {
      this.typeFactory = typeFactory;
    }
  
    public List<RelDataTypeField> getFieldList() {
      return fields;
    }
  
    public int getFieldCount() {
      return fields.size();
    }
  
    /**
     * Get field if exists, otherwise inserts a new field. The new field by default will have "any"
     * type, except for the dynamic star field.
     *
     * @param fieldName Request field name
     * @param caseSensitive Case Sensitive
     * @return A pair of RelDataTypeField and Boolean. Boolean indicates whether a new field is added
     * to this holder.
     */
    Pair<RelDataTypeField, Boolean> getFieldOrInsert(String fieldName, boolean caseSensitive) {
      // First check if this field name exists in our field list
      for (RelDataTypeField f : fields) {
        if (Util.matches(caseSensitive, f.getName(), fieldName)) {
          return Pair.of(f, false);
        }
        // A dynamic star field matches any field
        if (f.getType().getSqlTypeName() == SqlTypeName.DYNAMIC_STAR) {
          return Pair.of(f, false);
        }
      }
  
      final SqlTypeName typeName = DynamicRecordType.isDynamicStarColName(fieldName)
          ? SqlTypeName.DYNAMIC_STAR : SqlTypeName.ANY;
  
      // This field does not exist in our field list; add it
      RelDataTypeField newField =
          new RelDataTypeFieldImpl(fieldName,
              fields.size(),
              typeFactory.createTypeWithNullability(
                  typeFactory.createSqlType(typeName), true));
  
      // Add the name to our list of field names
      fields.add(newField);
  
      return Pair.of(newField, true);
    }
  
    public List<String> getFieldNames() {
      return Pair.left(fields);
    }
  
  }
  