Fold

All Known Implementing Classes:: FoldLeftFn.FoldLeftFold, Sum.SumFold

public interface Fold

Method Summary

Modifier and Type

Method

Description

boolean

isFinished()

Ask whether the computation has completed.

void

processItem(Item item)

Process one item in the input sequence, returning a new copy of the working data

Sequence

result()

Compute the final result of the function, when all the input has been processed

Method Details
- processItem
  
  void processItem(Item item) throws XPathException
  
  Process one item in the input sequence, returning a new copy of the working data
  
  Parameters:
  
  item - the item to be processed from the input sequence
  
  Throws:
  
  XPathException - if a dynamic error occurs
- isFinished
  
  boolean isFinished()
  
  Ask whether the computation has completed. A function that can deliver its final result without reading the whole input should return true; this will be followed by a call on result() to deliver the final result.
  
  Returns:
  
  true if the result of the function is now available even though not all items in the sequence have been processed
- result
  
  Sequence result() throws XPathException
  
  Compute the final result of the function, when all the input has been processed
  
  Returns:
  
  the result of the function
  
  Throws:
  
  XPathException - if a dynamic error occurs