package com.fayi.hutool.TreeUtil; import cn.hutool.core.lang.tree.Tree; import cn.hutool.core.lang.tree.TreeNodeConfig; import cn.hutool.core.lang.tree.TreeUtil; import cn.hutool.json.JSONUtil; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import java.util.ArrayList; import java.util.List; public class Demo { public static void main(String[] args) { List<User> users = new ArrayList<>(); users.add(new User("1", "", "0", "手机")); users.add(new User("2", "", "1", "小米")); users.add(new User("3", "", "1", "华为")); users.add(new User("4", "", "0", "水果")); users.add(new User("5", "", "4", "香蕉")); users.add(new User("6", "", "4", "菠萝")); TreeNodeConfig config = new TreeNodeConfig(); List<Tree<String>> treeList = TreeUtil.build(users, "0", config, (treeNode, tree) -> { tree.setId(treeNode.getId()); tree.setParentId(treeNode.getPid()); tree.setName(treeNode.getName()); }); System.out.println(JSONUtil.toJsonStr(treeList)); // 自定义字段名,userId 对应pid users.clear(); users.add(new User("1", "10", "0", "手机")); users.add(new User("2", "20", "10", "小米")); users.add(new User("3", "30", "10", "华为")); users.add(new User("4", "40", "0", "水果")); users.add(new User("5", "50", "40", "香蕉")); users.add(new User("6", "60", "40", "菠萝")); config.setIdKey("userId"); treeList = TreeUtil.build(users, "0", config, (treeNode, tree) -> { tree.setId(treeNode.getUserId()); tree.setParentId(treeNode.getPid()); tree.setName(treeNode.getName()); tree.putExtra("id", treeNode.getId()); }); System.out.println(JSONUtil.toJsonStr(treeList)); } } @NoArgsConstructor @AllArgsConstructor @Data class User { private String id; private String userId; private String pid; private String name; }
可以灵活配置,树形结果返回,不再需要自己写递归了
Hutool参考文档:https://hutool.cn/docs/#/core/%E8%AF%AD%E8%A8%80%E7%89%B9%E6%80%A7/%E6%A0%91%E7%BB%93%E6%9E%84/%E6%A0%91%E7%BB%93%E6%9E%84%E5%B7%A5%E5%85%B7-TreeUtil