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

Interface WriterEvents.ColumnWriterListener

All Known Implementing Classes:

ColumnState.PrimitiveColumnState

Enclosing interface:

WriterEvents

public static interface WriterEvents.ColumnWriterListener

Listener (callback) for vector overflow events. To be optionally implemented and bound by the client code of the writer. If no listener is bound, and a vector overflows, then an exception is thrown.

Method Summary

Modifier and Type	Method and Description
boolean	canExpand(ScalarWriter writer, int delta) A writer wants to expand its vector.
void	overflowed(ScalarWriter writer) Alert the listener that a vector has overflowed.

Method Detail

overflowed

void overflowed(ScalarWriter writer)

Alert the listener that a vector has overflowed. Upon return, all writers must have a new set of buffers available, ready to accept the in-flight value that triggered the overflow.

Parameters:

writer - the writer that triggered the overflow

canExpand

boolean canExpand(ScalarWriter writer,
                  int delta)

A writer wants to expand its vector. Allows the listener to either allow the growth, or trigger and overflow to limit batch size.

Parameters:

writer - the writer that wishes to grow its vector

delta - the amount by which the vector is to grow

Returns:

true if the vector can be grown, false if the writer should instead trigger an overflow by calling overflowed()