How to find maximum value from a Integer using stream in Java 8?
You may either convert the stream to IntStream: OptionalInt max = list.stream().mapToInt(Integer::intValue).max(); Or specify the natural order comparator: Optional<Integer> max = list.stream().max(Comparator.naturalOrder()); Or use reduce operation: Optional<Integer> max = list.stream().reduce(Integer::max); Or use collector: Optional<Integer> max = list.stream().collect(Collectors.maxBy(Comparator.naturalOrder())); Or use IntSummaryStatistics: int max = list.stream().collect(Collectors.summarizingInt(Integer::intValue)).getMax();