com.yahoo.sketches.tuple.SummarySetOperations Maven / Gradle / Ivy
/*
* Copyright 2015-16, Yahoo! Inc.
* Licensed under the terms of the Apache License 2.0. See LICENSE file at the project root for terms.
*/
package com.yahoo.sketches.tuple;
/**
* This is to provide methods of producing unions and intersections of two Summary objects.
* @param type of Summary
*/
public interface SummarySetOperations {
/**
* 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.
*
* @param a Summary from sketch A
* @param b Summary from sketch B
* @return union of Summary A and Summary B
*/
public S union(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.
*
* @param a Summary from sketch A
* @param b Summary from sketch B
* @return intersection of Summary A and Summary B
*/
public S intersection(S a, S b);
}