private Set<IndirectCriterionRequirement> copyIndirectRequirements(
Set<IndirectCriterionRequirement> collection) {
Set<IndirectCriterionRequirement> result = new HashSet<IndirectCriterionRequirement>();
for (IndirectCriterionRequirement requirement : collection) {
DirectCriterionRequirement parent = requirement.getParent();
IndirectCriterionRequirement newRequirement = IndirectCriterionRequirement
.create(parent, requirement.getCriterion());
newRequirement.setValid(requirement.isValid());
result.add(newRequirement);
}