private AddIssueLinkValidationResult validateAddIssueLinks(ApplicationUser user, Issue issue, IssueLinkType linkType, Direction direction, Collection<String> linkKeys, boolean excludeSystemLinks) { Assertions.notNull("issue", issue); Assertions.notNull("linkKeys", linkKeys); ErrorCollection errorCollection = validateIssuePermission(user, issue, Permissions.LINK_ISSUE); if (!errorCollection.hasAnyErrors()) { validateLinkInput(user, errorCollection, issue, linkType, linkKeys, excludeSystemLinks); } return new AddIssueLinkValidationResult(user, errorCollection, issue, linkType, direction, linkKeys); }