EventMappingIterator (saxon JavaDoc)

java.lang.Object
- net.sf.saxon.evpull.EventMappingIterator

All Implemented Interfaces:

EventIterator, PullEvent
```
public final class EventMappingIterator
extends java.lang.Object
implements EventIterator
```
MappingIterator merges a sequence of sequences into a single sequence. It takes as inputs an iteration, and a mapping function to be applied to each Item returned by that iteration. The mapping function itself returns another iteration. The result is an iteration of iterators. To convert this int a single flat iterator over a uniform sequence of events, the result must be wrapped in an EventStackIterator

Constructor Summary

Constructors
Constructor	Description
`EventMappingIterator(SequenceIterator base, EventMappingFunction action)`	Construct a MappingIterator that will apply a specified MappingFunction to each Item returned by the base iterator.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`isFlatSequence()`	Determine whether the EventIterator returns a flat sequence of events, or whether it can return nested event iterators
`PullEvent`	`next()`	Get the next event in the sequence

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - EventMappingIterator
```
public EventMappingIterator(SequenceIterator base,
                            EventMappingFunction action)
```
    Construct a MappingIterator that will apply a specified MappingFunction to each Item returned by the base iterator.
    
    Parameters:
    
    base - the base iterator
    
    action - the mapping function to be applied
- Method Detail
  - next
```
public PullEvent next()
               throws XPathException
```
    Description copied from interface: EventIterator
    
    Get the next event in the sequence
    
    Specified by:
    
    next in interface EventIterator
    
    Returns:
    
    the next event, or null when the sequence is exhausted. Note that since an EventIterator is itself a PullEvent, this method may return a nested iterator.
    
    Throws:
    
    XPathException - if a dynamic evaluation error occurs
  - isFlatSequence
```
public boolean isFlatSequence()
```
    Determine whether the EventIterator returns a flat sequence of events, or whether it can return nested event iterators
    
    Specified by:
    
    isFlatSequence in interface EventIterator
    
    Returns:
    
    true if the next() method is guaranteed never to return an EventIterator