public class LambdaTest {    public static void main(String[] args) {        // 相当于foreach遍历操作结果值        Integer out = Stream.of(10, 5, 3, 2, 1, 0).reduce((result, item) -> {            if (item >= 3) {                result = result + item;            }            return result;        }).get();        System.out.println(out);        // 相当于给定初始结果值，foreach遍历操作结果值        Integer sum = Stream.of(10, 5, 3, 2, 1, 0).reduce(9, LambdaTest::sumTest);        System.out.println(sum);        //相当于给定初始结果值，两个foreach遍历操作结果值        int str = Stream.of(1,2,3).parallel().reduce(1, (result, item) -> {            return result + item;        } , (result, item) -> {            //注：只有并行parallel下才会进入此方法            return result + item ;        });        System.out.println(str);    }    //替换Integer::sum测试    public static Integer sumTest(int a1, int a2) {        return a1 + a2;    }}