实体类：
package com.gsl.node.entity;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.List;
/**
* @Author ：Guo Shi Lin
* @date ： 2020/8/18 13:57
* @description：菜单树
* @modified By：
* @version: 1.0
*/
@Data
@NoArgsConstructor
@AllArgsConstructor
@TableName("tree")
public class Tree {
@TableId(value = "id", type = IdType.AUTO)
private Integer id;
private String name;
private Integer parentId;
@TableField(exist = false)
private List<Tree> children;
}
数据访问层接口dao：
外汇名词解释https://www.fx61.com/definitions
package com.gsl.node.dao;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.gsl.node.entity.Tree;
import org.apache.ibatis.annotations.Mapper;
/**
* @Author ：Guo Shi Lin
* @date ： 2020/8/18 13:58
* @description：
* @modified By：
* @version: 1.0
*/
@Mapper
public interface TreeDao extends BaseMapper<Tree> {
}
业务逻辑层接口service：
package com.gsl.node.service;
import com.gsl.node.entity.Tree;
import java.util.List;
/**
* @Author ：Guo Shi Lin
* @date ： 2020/8/18 13:58
* @description：
* @modified By：
* @version: 1.0
*/
public interface TreeService {
/**
* 查找树
* @return
*/
List<Tree> findList();
}
业务逻辑层实现类impl：
package com.gsl.node.service.impl;
import com.gsl.node.dao.TreeDao;
import com.gsl.node.entity.Tree;
import com.gsl.node.service.TreeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.ArrayList;
import java.util.List;
/**
* @Author ：Guo Shi Lin
* @date ： 2020/8/18 14:00
* @description：用的递归实现
* @modified By：
* @version: 1.0
*/
@Service
public class TreeServiceImpl implements TreeService {
@Autowired
private TreeDao treeDao;
@Override
public List<Tree> findList() {
return treeDao.selectList(null);
}
public List<Tree> handleTree() {
//根节点list
List<Tree> treeList = new ArrayList<>();
//从数据库获取所有得数据
List<Tree> allTree = treeDao.selectList(null);
if (null != allTree && allTree.size() > 0) {
allTree.forEach(tree -> {
if (tree.getParentId() == 0) {
treeList.add(tree);
}
});
if (null != treeList && treeList.size() > 0) {
treeList.forEach(tree -> {
//使用递归获取孩子
List<Tree> childrenList = getChildren(tree.getId(), allTree);
tree.setChildren(childrenList);
});
}
}
return treeList;
}
/**
* 使用递归获取根节点下面得孩子
* @param id
* @param allTree
* @return
*/
public List<Tree> getChildren(Integer id, List<Tree> allTree) {
List<Tree> childrenList = new ArrayList<>();
allTree.forEach(tree -> {
if (tree.getParentId().equals(id)) {
childrenList.add(tree);
}
});
if (null != childrenList && childrenList.size() > 0) {
childrenList.forEach(tree -> {
tree.setChildren(getChildren(tree.getId(), allTree));
});
} else {
return null;
}
return childrenList;
}
}
控制层controller：
package com.gsl.node.controller;
import com.gsl.node.entity.Tree;
import com.gsl.node.service.TreeService;
import com.gsl.node.service.impl.TreeServiceImpl;
import com.gsl.result.ResponseResult;
import io.swagger.annotations.Api;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
/**
* @Author ：Guo Shi Lin
* @date ： 2020/8/19 9:37
* @description：
* @modified By：
* @version: 1.0
*/
@RestController
@Api(tags = "树")
public class TreeController {
@Autowired
private TreeServiceImpl treeService;
@GetMapping("tree")
public ResponseResult<Tree> tree() {
return new ResponseResult(200, "成功", treeService.handleTree());
}
}
3.测试结果
{
"code": 200,
"msg": "成功",
"data": [
{
"id": 1,
"name": "根节点",
"parentId": 0,
"children": [
{
"id": 2,
"name": "父节点",
"parentId": 1,
"children": [
{
"id": 3,
"name": "子节点",
"parentId": 2,
"children": null
},
{
"id": 4,
"name": "子节点-1",
"parentId": 2,
"children": null
}
]
},
{
"id": 5,
"name": "父节点-1",
"parentId": 1,
"children": null
}
]
},
{
"id": 6,
"name": "根节点-1",
"parentId": 0,
"children": null
}
]
}
|
|
收藏
淘帖
踩
