List<Integer> intList = Arrays.asList(1,2,3); Optional<Integer> result1=intList.stream().reduce(Integer::sum); Integer result2=intList.stream().reduce(100, Integer::sum); System.out.println(result2); int value1 = Stream.of(1, 2, 3, 4, 5).reduce(new BinaryOperator<Integer>() { @Override public Integer apply(Integer integer, Integer integer2) { return integer + integer2; } }).get(); System.out.println(value1); //带初始值 int value2 = Stream.of(1, 2, 3, 4, 5).reduce(100, (item1, item2) -> item1 + item2); System.out.println(value2); //求出最大值 int value3 = Stream.of(1645, 234345, 32, 44434, 564534, 435, 34343542, 212) .reduce((item1, item2) -> item1 > item2 ? item1 : item2).get(); System.out.println(value3);
控制台输出

本文作者为DBC,转载请注明。