org.hypergraphdb.query.impl

Class FilteredResultSet<T>

java.lang.Object

org.hypergraphdb.query.impl.FilteredResultSet<T>

All Implemented Interfaces:

Iterator<T>, HGSearchResult<T>, TwoWayIterator<T>, CloseMe

Direct Known Subclasses:

FilteredRAResultSet

public class FilteredResultSet<T>
extends Object
implements HGSearchResult<T>

Filter a result set through a predicate.

Author:

Borislav Iordanov

Field Summary

Fields inherited from interface org.hypergraphdb.HGSearchResult

EMPTY

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FilteredResultSet()
	FilteredResultSet(HGSearchResult<T> searchResult, Mapping<T,Boolean> predicate, int lookahead) The constructor assumes the underlying set is already positioned to the first matching entity.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Free all system resources held up by the result set and invalidate it for further use.
T	current() Returns the current element in the result set.
boolean	hasNext()
boolean	hasPrev() Return true if there is a previous element in the current iteration state and false otherwise.
boolean	isOrdered() Return true if the elements in this search result are in ordered and false otherwise.
T	next()
T	prev() Returns the previous element in this iteration.
void	remove()

Methods inherited from class java.lang.Object

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

Constructor Detail

FilteredResultSet

protected FilteredResultSet()

FilteredResultSet

public FilteredResultSet(HGSearchResult<T> searchResult,
                 Mapping<T,Boolean> predicate,
                 int lookahead)

The constructor assumes the underlying set is already positioned to the first matching entity.

Parameters:

hg - The

searchResult -

predicate -

Method Detail

close

public void close()

Description copied from interface: HGSearchResult

Free all system resources held up by the result set and invalidate it for further use.

Specified by:

close in interface HGSearchResult<T>

Specified by:

close in interface CloseMe

current

public T current()

Description copied from interface: HGSearchResult

Returns the current element in the result set. If there is no current element, java.util.NoSuchElementException is thrown. There is no current element if the next method was never invoked.

Specified by:

current in interface HGSearchResult<T>

Returns:

The current element in a HGSearchResult.

hasPrev

public boolean hasPrev()

Description copied from interface: TwoWayIterator

Return true if there is a previous element in the current iteration state and false otherwise. After the iterator has been initialized, the value of hasPrev will always be false.

Specified by:

hasPrev in interface TwoWayIterator<T>

prev

public T prev()

Description copied from interface: TwoWayIterator

Returns the previous element in this iteration.

Specified by:

prev in interface TwoWayIterator<T>

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T>

next

public T next()

Specified by:

next in interface Iterator<T>

remove

public void remove()

Specified by:

remove in interface Iterator<T>

isOrdered

public boolean isOrdered()

Description copied from interface: HGSearchResult

Return true if the elements in this search result are in ordered and false otherwise. It is assumed that when elements are ordered, they are instances of java.lang.Comparable

Specified by:

isOrdered in interface HGSearchResult<T>