Java - Stream Filter 多条件筛选过滤-编程知识

Java - Stream Filter 多条件筛选过滤

Java Stream流中Filter用于通过设置的条件过滤出元素，示例如下：

List strings = Arrays.asList(“abc”, “”, “bc”, “efg”, “abcd”,"", “jkl”);List filtered = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.toList());

如果需要进行多条件过滤

我们可以对这些参数进行处理，我们只是需要做一下判断，即：

让所有参数默认为 false，然后对传进来的值进行取值判断，若满足该条件为true，多个条件进行多次判断

判断完成之后会拿到所有的boolean值通过 && 拼接返回，即有一个为false，即返回值为false

通过该方法会对一个对象进行多条件过滤

public static List<BidListVo> checkOperationv1(List<BidListVo> list, BidProgressEnum progressEnum){Integer progress = Integer.valueOf(progressEnum.getCode());String nodeId = progressEnum.getNode();List<BidListVo> collect = list.stream().filter(bidListVo -> filterProgress(bidListVo,progress)  ).collect(Collectors.toList());return collect;}private static boolean filterProgress(BidListVo bidListVo, Integer progress) {//副流程未开始 只判断主流程if(StringUtils.isEmpty(bidListVo.getReviewProgress())){return Integer.valueOf(bidListVo.getProgress()) >= progress ? true: false;}else if(Integer.valueOf(bidListVo.getProgress()) >= progress ||Integer.valueOf(bidListVo.getReviewProgress()) >= progress){// 主流程 独立流程 任意一个大于当前筛选进度就好return true;}return false;}

示例

public class MultiFilterTest {public static void main(String[] args) {List<User> userList = getUserList();// 筛选 age > 18 && address = "上海" 的userList<User> filterList = userList.stream().filter(user -> filterAgeAndAddress(user,18,"上海")).collect(Collectors.toList());filterList.forEach(System.out::println);}// 筛选 age > 18 && address = "上海" 的userprivate static boolean filterAgeAndAddress(User user,Integer age,String address){if(user.getAge() > 18 && address.equals(user.getAddress())){return true;}return false;}private static List<User> getUserList() {List<User> userList = new ArrayList<>();userList.add(new User(1,"张三",18,"上海"));userList.add(new User(2,"王五",16,"上海"));userList.add(new User(3,"李四",20,"上海"));userList.add(new User(4,"张雷",22,"北京"));userList.add(new User(5,"张超",15,"深圳"));userList.add(new User(6,"李雷",24,"北京"));userList.add(new User(7,"王爷",21,"上海"));userList.add(new User(8,"张三丰",18,"广州"));userList.add(new User(9,"赵六",16,"广州"));userList.add(new User(10,"赵无极",26,"深圳"));return userList;}
}

输出如下：