org.apache.jackrabbit.commons.iterator
Class FilteredRangeIterator

java.lang.Object
  org.apache.jackrabbit.commons.iterator.FilteredRangeIterator

All Implemented Interfaces:

Iterator, RangeIterator

public class FilteredRangeIterator
extends Object
implements RangeIterator

Filtering decorator for iterators.

Constructor Summary

FilteredRangeIterator(Iterator<?> iterator)
Creates a pre-fetching decorator for the given iterator.

FilteredRangeIterator(Iterator<?> iterator, Predicate predicate)
Creates a new filtered iterator with the default pre-fetch buffer size.

FilteredRangeIterator(Iterator<?> iterator, Predicate predicate, int bufferSize)
Creates a new filtered iterator.

Method Summary

long	getPosition() Returns the zero-based position of the next element in this iterator.
long	getSize() Returns the total number of elements in this iterator, or -1 if that number is unknown.
boolean	hasNext() Checks whether there are more elements in this iterator.
Object	next() Returns the next element in this iterator.
void	remove() Not supported.
void	skip(long n) Skips the next n elements.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FilteredRangeIterator

public FilteredRangeIterator(Iterator<?> iterator,
                             Predicate predicate,
                             int bufferSize)

Creates a new filtered iterator.

Parameters:

iterator - underlying iterator

predicate -

bufferSize -

FilteredRangeIterator

public FilteredRangeIterator(Iterator<?> iterator,
                             Predicate predicate)

Creates a new filtered iterator with the default pre-fetch buffer size.

Parameters:

iterator - underlying iterator

predicate - predicate used for filtering

FilteredRangeIterator

public FilteredRangeIterator(Iterator<?> iterator)

Creates a pre-fetching decorator for the given iterator. This constructor is mostly useful when it is desirable to use the pre-fetching feature to automatically

Parameters:

iterator - underlying iterator

predicate - predicate used for filtering

Method Detail

getPosition

public long getPosition()

Returns the zero-based position of the next element in this iterator.

Specified by:

getPosition in interface RangeIterator

Returns:

position of the next element

getSize

public long getSize()

Returns the total number of elements in this iterator, or -1 if that number is unknown.

Specified by:

getSize in interface RangeIterator

Returns:

number of elements in this iterator, or -1

skip

public void skip(long n)
          throws IllegalArgumentException,
                 NoSuchElementException

Skips the next n elements.

Specified by:

skip in interface RangeIterator

Parameters:

n - number of elements to skip

Throws:

IllegalArgumentException - if n is negative

NoSuchElementException - if there are not enough elements to skip

hasNext

public boolean hasNext()

Checks whether there are more elements in this iterator.

Specified by:

hasNext in interface Iterator

Returns:

true if there are more elements, false otherwise

next

public Object next()
            throws NoSuchElementException

Returns the next element in this iterator.

Specified by:

next in interface Iterator

Returns:

next element

Throws:

NoSuchElementException - if there are no more elements

remove

public void remove()
            throws UnsupportedOperationException

Not supported.

Specified by:

remove in interface Iterator

Throws:

UnsupportedOperationException