com.bigdata.bop.join

Interface IDistinctFilter

All Known Implementing Classes:

JVMDistinctFilter

public interface IDistinctFilter

A "DISTINCT" filter for IBindingSets.

Author:

Bryan Thompson

Method Summary

Methods

Modifier and Type	Method and Description
IBindingSet	accept(IBindingSet bset) If the bindings are distinct for the configured variables then return a new IBindingSet consisting of only the selected variables.
long	filterSolutions(ICloseableIterator<IBindingSet[]> itr, BOpStats stats, IBuffer<IBindingSet> sink) Vectored DISTINCT.
IVariable<?>[]	getProjectedVars() The variables that are being projected out of the DISTINCT filter.
void	release() Discard the map backing this filter.

Method Detail

getProjectedVars

IVariable<?>[] getProjectedVars()

The variables that are being projected out of the DISTINCT filter. The solutions will be DISTINCT on this combination of variables. Bindings on other variables will be dropped.

accept

IBindingSet accept(IBindingSet bset)

If the bindings are distinct for the configured variables then return a new IBindingSet consisting of only the selected variables.

Parameters:

bset - The binding set to be filtered.

Returns:

A new IBindingSet containing only the distinct as bound values -or- null if the binding set duplicates a solution which was already accepted.

filterSolutions

long filterSolutions(ICloseableIterator<IBindingSet[]> itr,
                   BOpStats stats,
                   IBuffer<IBindingSet> sink)

Vectored DISTINCT.

Parameters:

itr - The source solutions.

stats - Statistics object to be updated.

sink - The sink onto which the DISTINCT solutions will be written.

Returns:

The #of DISTINCT solutions.

release

void release()

Discard the map backing this filter.