private def aliasToString()

in modules/spark-ext/spark/src/main/scala/org/apache/ignite/spark/impl/optimization/SimpleExpressions.scala [129:191]
39 lines of code
16 McCabe index (conditional complexity)

    private def aliasToString(column: String, alias: String): String =
        if (isAliasEqualColumnName(alias, column))
            column
        else if (alias.matches("[A-Za-z_][0-9A-Za-z_]*"))
            s"$column AS $alias"
        else
            s"""$column AS "$alias""""

    /**
      * @param alias Alias.
      * @param column Column.
      * @return True if name equals to alias, false otherwise.
      */
    private def isAliasEqualColumnName(alias: String, column: String): Boolean =
        alias.compareToIgnoreCase(column.replaceAll("'", "")) == 0

    /**
      * @param from From type conversion.
      * @param to To type conversion.
      * @return True if cast support for types, false otherwise.
      */
    private def castSupported(from: DataType, to: DataType): Boolean = from match {
        case BooleanType ⇒
            Set[DataType](BooleanType, StringType)(to)

        case ByteType ⇒
            Set(ByteType, ShortType, IntegerType, LongType, FloatType, DoubleType, StringType, DecimalType(_, _),
                StringType)(to)

        case ShortType ⇒
            Set(ShortType, IntegerType, LongType, FloatType, DoubleType, StringType, DecimalType(_, _))(to)

        case IntegerType ⇒
            Set(IntegerType, LongType, FloatType, DoubleType, StringType, DecimalType(_, _))(to)

        case LongType ⇒
            Set(LongType, FloatType, DoubleType, StringType, DecimalType(_, _))(to)

        case FloatType ⇒
            Set(FloatType, DoubleType, StringType, DecimalType(_, _))(to)

        case DoubleType ⇒
            Set(DoubleType, StringType, DecimalType(_, _))(to)

        case DecimalType() ⇒
            Set(StringType, DecimalType(_, _))(to)

        case DateType ⇒
            Set[DataType](DateType, StringType, LongType, TimestampType)(to)

        case TimestampType ⇒
            Set[DataType](TimestampType, DateType, StringType, LongType)(to)

        case StringType ⇒
            Set(BooleanType, ByteType, ShortType, IntegerType, LongType, FloatType, DoubleType,
                DecimalType(_, _), DateType, TimestampType, StringType)(to)

        case BinaryType ⇒
            false

        case ArrayType(_, _) ⇒
            false
    }