Package org.apache.drill.exec.vector.accessor

Interface ScalarWriter

All Superinterfaces:
ColumnWriter, ValueWriter
All Known Subinterfaces:
OffsetVectorWriter
All Known Implementing Classes:
AbstractFixedWidthWriter, AbstractFixedWidthWriter.BaseFixedWidthWriter, AbstractFixedWidthWriter.BaseIntWriter, AbstractScalarWriter, AbstractScalarWriterImpl, BaseScalarWriter, BaseVarWidthWriter, BitColumnWriter, ColumnAccessors.BigIntColumnWriter, ColumnAccessors.DateColumnWriter, ColumnAccessors.Decimal18ColumnWriter, ColumnAccessors.Decimal28SparseColumnWriter, ColumnAccessors.Decimal38SparseColumnWriter, ColumnAccessors.Decimal9ColumnWriter, ColumnAccessors.Float4ColumnWriter, ColumnAccessors.Float8ColumnWriter, ColumnAccessors.IntColumnWriter, ColumnAccessors.IntervalColumnWriter, ColumnAccessors.IntervalDayColumnWriter, ColumnAccessors.IntervalYearColumnWriter, ColumnAccessors.SmallIntColumnWriter, ColumnAccessors.TimeColumnWriter, ColumnAccessors.TimeStampColumnWriter, ColumnAccessors.TinyIntColumnWriter, ColumnAccessors.UInt1ColumnWriter, ColumnAccessors.UInt2ColumnWriter, ColumnAccessors.UInt4ColumnWriter, ColumnAccessors.UInt8ColumnWriter, ColumnAccessors.Var16CharColumnWriter, ColumnAccessors.VarBinaryColumnWriter, ColumnAccessors.VarCharColumnWriter, ColumnAccessors.VarDecimalColumnWriter, DummyArrayWriter.DummyOffsetVectorWriter, DummyScalarWriter, NullableScalarWriter, OffsetVectorWriterImpl
public interface ScalarWriter extends ColumnWriter, ValueWriter
Represents a scalar value: a required column, a nullable column, or one element within an array of scalars.

Vector values are mapped to their "natural" representations: the representation closest to the actual vector value. For date and time values, this generally means a numeric value. Applications can then map this value to Java objects as desired. Decimal types all map to BigDecimal as that is the only way in Java to represent large decimal values.

In general, a column maps to just one value. However, derived classes may choose to provide type conversions if convenient. An exception is thrown if a call is made to a method that is not supported by the column type.

  • Method Details

    • valueType

      ValueType valueType()
      Describe the type of the value. This is a compression of the value vector type: it describes which method will return the vector value.
      Returns:
      the value type which indicates which get method is valid for the column

    • extendedType

      ValueType extendedType()
      The extended type of the value, describes the secondary type for DATE, TIME and TIMESTAMP for which the value type is int or long.

    • setDefaultValue

      void setDefaultValue(Object value)
      Set the default value to be used to fill empties for this writer. Only valid for required writers: null writers set this is-set bit to 0 and set the data value to 0.
      Parameters:
      value - the value to set. Cannot be null. The type of the value must match that legal for ValueWriter.setValue(Object)