class A{ void method(){ IntStream.range(1,5).map(a->a+1) .map((a)->a+1) // Noncompliant {{Remove the parentheses around the "a" parameter (sonar.java.source not set. Assuming 8 or greater.)}} .map((int x)->x+1) ; Collectors.groupingBy((Map<String, Object> page) -> Site.category(page), TreeMap::new, toList()); } }