java8 stream

 List<Emplyee> list = Arrays.asList(
                new Emplyee(10, "张三", 15, 9000),
                new Emplyee(10, "李四", 19, 9000),
                new Emplyee(10, "王五", 45, 9000),
                new Emplyee(10, "赵六", 78, 9000),
                new Emplyee(10, "赵六", 78, 9000),
                new Emplyee(10, "赵六", 78, 9000),
                new Emplyee(10, "张si", 10, 9000)
        );
 List<Integer> i = Arrays.asList(1,1,12,23,23,78,53,99,13,42);

两个测试的list

1.filter  过滤

        list.stream().filter((x)->x.getAge()>20)
                .forEach(System.out::println);


结果 
Emplyee{id=10, name='王五', age=45, sal=9000}
Emplyee{id=10, name='赵六', age=78, sal=9000}
Emplyee{id=10, name='赵六', age=78, sal=9000}
Emplyee{id=10, name='赵六', age=78, sal=9000}

2.distinct  去重

i.stream().distinct()
                .forEach(System.out::println);

结果
1
12
23
78
53
99
13
42

3.collection    传送门 ：https://www.cnblogs.com/zszxz/p/12066903.html