Package org.zkoss.pivot.impl.calc
Interface Context<C extends Context<C>>
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- All Known Implementing Classes:
MinMaxContext
,ProductContext
,SumCountContext
,VarianceContext
public interface Context<C extends Context<C>>
The context to hold intermediate result of an aggregation. For example, to calculate arithmetic average, we need to accumulate SUM and COUNT. It is provable that if an aggregation over a collection is order independent and its computation can be carried out via a context data type with a binary operator, then the context can also be merged from contexts over a partition of the original collection.- Author:
- simonpai
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Method Summary
All Methods Instance Methods Abstract Methods Modifier and Type Method Description void
add(Object item)
Add an item into the aggregation.void
merge(C ctx)
Merge from another context of the same type.
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