org.opensaml.xml.security
Class CriteriaFilteringIterator<T>

java.lang.Object
  org.opensaml.xml.security.CriteriaFilteringIterator<T>

Type Parameters:

T - the type of candidate elements being evaluated

All Implemented Interfaces:

Iterator<T>

public class CriteriaFilteringIterator<T>
extends Object
implements Iterator<T>

This implementation of Iterator wraps another Iterator of a particular type, containing candidates which are to be evaluated against a given set of EvaluableCriteria. When the iterator is traversed, criteria evaluation is performed on each candidate element of the underlying wrapped iterator via EvaluableCriteria.evaluate(Object). Only those elements which satisfy the criteria indicated by the criteria set are returned by the Iterator, as follows.

If the parameter meetAllCriteria is true, then all criteria in the criteria set must be satisfied in order for the element to be returned. This in essence connects the criteria of the criteria set with a logical AND. If false, then if an element satisfies any of the criteria of the criteria set, it will be returned. This in essence connects the members of the criteria set with a logical OR.

If the parameter unevaluableSatisfies is true, then if a criteria's evaluation of the candidate via EvaluableCriteria.evaluate(Object) indicates that it is unable to evaluate the candidate, the criteria will be considered satisfied as far as the determination of whether to return the candidate. If false, then the criteria will be considered unsatisfied for purposes of this determination.

Care should be exercised in combining these two parameter values to achieve the desired result.

Field Summary

private Iterator<? extends T>	candidateIter The candidates to evaluate.
private Set<EvaluableCriteria<T>>	criteriaSet The set of criteria against which to evaluate the candidates.
private T	current The current candidate which will be returned by the next call to next().
private boolean	meetAll Flag indicating whether the candidate must satisfy all the criteria in the set, or just one.
private boolean	unevaledSatisfies Flag indicating how candidates which can not be evaluated by a criteria are to be handled.

Constructor Summary

CriteriaFilteringIterator(Iterator<? extends T> candidatesIterator, Set<EvaluableCriteria<T>> criteria, boolean meetAllCriteria, boolean unevaluableSatisfies)
Constructor.

Method Summary

private T	getNextMatch() Get the next matching candidate.
boolean	hasNext()
private boolean	match(T candidate) Evaluate the candidate against all the criteria.
T	next()
void	remove()

Methods inherited from class java.lang.Object

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

Field Detail

candidateIter

private Iterator<? extends T> candidateIter

The candidates to evaluate.

criteriaSet

private Set<EvaluableCriteria<T>> criteriaSet

The set of criteria against which to evaluate the candidates.

meetAll

private boolean meetAll

Flag indicating whether the candidate must satisfy all the criteria in the set, or just one.

unevaledSatisfies

private boolean unevaledSatisfies

Flag indicating how candidates which can not be evaluated by a criteria are to be handled.

current

private T current

The current candidate which will be returned by the next call to next().

Constructor Detail

CriteriaFilteringIterator

public CriteriaFilteringIterator(Iterator<? extends T> candidatesIterator,
                                 Set<EvaluableCriteria<T>> criteria,
                                 boolean meetAllCriteria,
                                 boolean unevaluableSatisfies)

Constructor.

Parameters:

candidatesIterator - the candidates to evaluate

criteria - the set of criteria against which to evaluate the candidates

meetAllCriteria - whether a candidate must meet all criteria, or just one

unevaluableSatisfies - whether a can-not-evaluate result of a particular criteria's evaluation is treated as the candidate having satisfied or not satisfied the criteria, for purposes of determinig whether to return the element

Method Detail

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>

getNextMatch

private T getNextMatch()

Get the next matching candidate.

Returns:

the next matching candidate

match

private boolean match(T candidate)

Evaluate the candidate against all the criteria.

Parameters:

candidate - the candidate to evaluate

Returns:

true if the candidate satisfies the set of criteria, false otherwise