Java-Stream filter 过滤数据
filter可用于条件过滤list集合中的元素。
一、filter 条件过滤
public void test()
{
List<userInfo> userList = new ArrayList<>();
//userInfo字段 UserId; Age; NickName; Sex 1:男 2:女
userList.add(new userInfo(1,22,"小明",1));
userList.add(new userInfo(2,22,"小红",2));
userList.add(new userInfo(3,24,"小张",1));
//过滤出年龄大于22的用户
List<userInfo> filterUser1 = userList.stream().filter(s -> s.getAge() > 22).collect(Collectors.toList());
//过滤出年龄等于22,且是男性用户
List<userInfo> filterUser2 = userList.stream().filter(s -> s.getAge() > 22 && s.getSex() == 1).collect(Collectors.toList());
}
public void test1()
{
List<String> strings = Arrays.asList("a", "", "b", "c");
//过滤出"a" "b"
List<String> filterUser1 = strings.stream().filter(s -> s.equals("a") || s.equals("b")).collect(Collectors.toList());
}