void (PsiExpression delimiterArgument, ProblemsHolder holder) { if (delimiterArgument instanceof PsiLiteralExpression literal && literal.getValue() instanceof String delimiters) { final Set<Character> chars = new HashSet<>(); for (char c : delimiters.toCharArray()) { if (!chars.add(c)) { holder.problem(delimiterArgument, JavaAnalysisBundle.message("delimiters.argument.contains.duplicated.characters")) .fix(new ReplaceDelimitersWithUnique(literal)).register(); return; } } } }