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;
  
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.sql.parser.SqlParserPos;
  import org.apache.calcite.sql.type.SqlTypeName;
  import org.apache.calcite.sql.validate.SqlValidator;
  import org.apache.calcite.util.Litmus;
  
  /**
   * Parse SQL MAP type, i.e. MAP&lt;INT NOT NULL, TIMESTAMP NULL&gt;, the key and value can specify a
   * suffix to indicate if the type is nullable, default is not null.
   *
   * <p>MAP type does not belong to standard SQL.
   */
  public class SqlMapTypeNameSpec extends SqlTypeNameSpec {
  
    private final SqlDataTypeSpec keyType;
    private final SqlDataTypeSpec valType;
  
    /**
     * Creates a {@code SqlMapTypeNameSpec}.
     *
     * @param keyType key type
     * @param valType value type
     * @param pos the parser position
     */
    public SqlMapTypeNameSpec(SqlDataTypeSpec keyType, SqlDataTypeSpec valType, SqlParserPos pos) {
      super(new SqlIdentifier(SqlTypeName.MAP.getName(), pos), pos);
      this.keyType = keyType;
      this.valType = valType;
    }
  
    public SqlDataTypeSpec getKeyType() {
      return keyType;
    }
  
    public SqlDataTypeSpec getValType() {
      return valType;
    }
  
    @Override public RelDataType deriveType(SqlValidator validator) {
      boolean keyCanBeNullable = validator.getTypeFactory().getTypeSystem().mapKeysCanBeNullable();
      RelDataType kType =
          keyType.deriveType(validator, keyCanBeNullable);
  
      RelDataType valueType = valType.deriveType(validator, true);
  
      return validator
          .getTypeFactory()
          .createMapType(kType, valueType);
    }
  
    @Override public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
      writer.keyword("MAP");
      SqlWriter.Frame frame = writer.startList(SqlWriter.FrameTypeEnum.FUN_CALL, "<", ">");
      writer.sep(","); // configures the writer
      keyType.unparse(writer, leftPrec, rightPrec);
      // Default is not null.
      if (Boolean.TRUE.equals(keyType.getNullable())) {
        writer.keyword("NULL");
      }
      writer.sep(",");
      valType.unparse(writer, leftPrec, rightPrec);
      // Default is not null.
      if (Boolean.TRUE.equals(valType.getNullable())) {
        writer.keyword("NULL");
      }
      writer.endList(frame);
    }
  
    @Override public boolean equalsDeep(SqlTypeNameSpec spec, Litmus litmus) {
      if (!(spec instanceof SqlMapTypeNameSpec)) {
        return litmus.fail("{} != {}", this, spec);
      }
      SqlMapTypeNameSpec that = (SqlMapTypeNameSpec) spec;
      if (!this.keyType.equalsDeep(that.keyType, litmus)) {
        return litmus.fail("{} != {}", this, spec);
      }
      if (!this.valType.equalsDeep(that.valType, litmus)) {
        return litmus.fail("{} != {}", this, spec);
      }
      return litmus.succeed();
    }
  }
  