org.apache.datasketches.tuple

Interface SummarySetOperations<S extends Summary>

Type Parameters:

S - type of Summary

All Known Implementing Classes:

ArrayOfStringsSummarySetOperations, DoubleSummarySetOperations, IntegerSummarySetOperations

public interface SummarySetOperations<S extends Summary>

This is to provide methods of producing unions and intersections of two Summary objects.

Method Summary

Modifier and Type	Method and Description
S	intersection(S a, S b) This is called when an intersection of two sketches is produced, and both sketches have the same key.
S	union(S a, S b) This is called when a union of two sketches is produced, and both sketches have the same key.

Method Detail

union

S union(S a,
        S b)

This is called when a union of two sketches is produced, and both sketches have the same key.

Caution: Do not modify the input Summary objects. Also do not return them directly, unless they are immutable (most Summary objects are not). For mutable Summary objects, it is important to create a new Summary object with the correct contents to be returned. Do not return null summaries.

Parameters:

a - Summary from sketch A

b - Summary from sketch B

Returns:

union of Summary A and Summary B

intersection

S intersection(S a,
               S b)

This is called when an intersection of two sketches is produced, and both sketches have the same key.

Caution: Do not modify the input Summary objects. Also do not return them directly, unless they are immutable (most Summary objects are not). For mutable Summary objects, it is important to create a new Summary object with the correct contents to be returned. Do not return null summaries.

Parameters:

a - Summary from sketch A

b - Summary from sketch B

Returns:

intersection of Summary A and Summary B