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

Class AbstractFixedWidthWriter.BaseFixedWidthWriter

java.lang.Object
org.apache.drill.exec.vector.accessor.writer.AbstractScalarWriter
org.apache.drill.exec.vector.accessor.writer.AbstractScalarWriterImpl
org.apache.drill.exec.vector.accessor.writer.BaseScalarWriter
org.apache.drill.exec.vector.accessor.writer.AbstractFixedWidthWriter
org.apache.drill.exec.vector.accessor.writer.AbstractFixedWidthWriter.BaseFixedWidthWriter
All Implemented Interfaces:
ColumnWriter, ScalarWriter, ValueWriter, WriterEvents, WriterPosition
Direct Known Subclasses:
AbstractFixedWidthWriter.BaseIntWriter, ColumnAccessors.BigIntColumnWriter, ColumnAccessors.DateColumnWriter, ColumnAccessors.Decimal18ColumnWriter, ColumnAccessors.Decimal28SparseColumnWriter, ColumnAccessors.Decimal38SparseColumnWriter, ColumnAccessors.Decimal9ColumnWriter, ColumnAccessors.Float4ColumnWriter, ColumnAccessors.Float8ColumnWriter, ColumnAccessors.IntervalColumnWriter, ColumnAccessors.IntervalDayColumnWriter, ColumnAccessors.IntervalYearColumnWriter, ColumnAccessors.TimeColumnWriter, ColumnAccessors.TimeStampColumnWriter, ColumnAccessors.UInt4ColumnWriter, ColumnAccessors.UInt8ColumnWriter
Enclosing class:
AbstractFixedWidthWriter
public abstract static class AbstractFixedWidthWriter.BaseFixedWidthWriter extends AbstractFixedWidthWriter

  • Constructor Details

    • BaseFixedWidthWriter

      public BaseFixedWidthWriter()

  • Method Details

    • prepareWrite

      protected final int prepareWrite()
      Determine the write index, growing, overflowing and back-filling the vector as needed.

      This is a bit tricky. This method has side effects, by design. The current vector buffer, and buffer address, will change in this method when a vector grows or overflows. So, don't use this method in inline calls of the form
      vector.getBuffer().doSomething(prepareWrite());
      The buffer obtained by getBuffer() can be different than the current buffer after prepareWrite().

      Returns:
      the index at which to write the current value

    • prepareWrite

      protected final int prepareWrite(int writeIndex)

    • fillEmpties

      protected final void fillEmpties(int writeIndex)
      Fill empties. This is required because the allocated memory is not zero-filled. Also allows filling a non-nullable vector with a defined default value.
      Specified by:
      fillEmpties in class AbstractFixedWidthWriter