使用Hutool实现树状层级结构

川长思鸟来 2024-03-26 15:27 60阅读 0赞

### 标题最近看Hutool中的TreeUtil工具包, 能比较简单的获取树状层级结构的功能, 记录一下: ###

##### 获取树状结构 : #####

1.  sql脚本

SET NAMES utf8mb4;
    SET FOREIGN_KEY_CHECKS = 0;
    
    -- ----------------------------
    -- Table structure for dev_department
    -- ----------------------------
    DROP TABLE IF EXISTS `dev_department`;
    CREATE TABLE `dev_department`  (
      `department_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '部门编号',
      `dcode` int(11) NULL DEFAULT NULL COMMENT '部门代码',
      `department_name` varchar(30) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT '' COMMENT '部门名称',
      `parent_department_id` int(12) NULL DEFAULT 0 COMMENT '父级部门id',
      PRIMARY KEY (`department_id`) USING BTREE
    ) ENGINE = InnoDB AUTO_INCREMENT = 22 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci COMMENT = '部门表' ROW_FORMAT = Dynamic;
    
    -- ----------------------------
    -- Records of dev_department
    -- ----------------------------
    INSERT INTO `dev_department` VALUES (1, 37, '股东大会', 0);
    INSERT INTO `dev_department` VALUES (2, 3701, '董事会', 1);
    INSERT INTO `dev_department` VALUES (3, 370101, '秘书处', 2);
    INSERT INTO `dev_department` VALUES (4, 37010101, '行政办公室', 3);
    
    SET FOREIGN_KEY_CHECKS = 1;

![树状结构图][334242d44ade4185ad1875760ee47270.png_pic_center]  
2. pom.xml

<dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <scope>runtime</scope>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-jdbc</artifactId>
            </dependency>
    
            <dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-boot-starter</artifactId>
                <version>3.5.2</version>
            </dependency>

1.  application.yml

spring:
      datasource:
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://47.103.53.133:3307/dbtest?characterEncoding=utf-8
        username: root
        password: root

1.  实体类

package com.itstone.mok.amooczl.treenode;
    
    import com.baomidou.mybatisplus.annotation.TableName;
    import lombok.Data;
    
    // 版本一: 
    // 注: 这里的@TableField注解可以省略不写, MyBatis-Plus会自动将实体类的驼峰属性与数据库中的下划线字段做映射。
    @Data
    @TableName("dev_department")
    public class Department {
        
    
        @TableField("department_id")
        private Integer departmentId;
        
        @TableField("dcode")
        private Integer dcode;
        
        @TableField("department_name")
        private String departmentName;
    
        @TableField("parent_department_id")
        private Integer parentDepartmentId;
    
    }

package com.itstone.mok.amooczl.treenode;
    
    import com.baomidou.mybatisplus.annotation.TableField;
    import com.baomidou.mybatisplus.annotation.TableName;
    import lombok.Data;
    
    // 版本二:
    @Data
    @TableName(value = "dev_department", autoResultMap = true)
    public class Department {
        
    
        @TableField("department_id")
        private Integer department_id;
    
        @TableField("dcode")
        private Integer dcode;
    
        @TableField("department_name")
        private String department_name;
    
        @TableField("parent_department_id")
        private Integer parent_department_id;
    
    }

1.  Mapper文件:

package com.itstone.mok.amooczl.treenode;
    
    import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import org.apache.ibatis.annotations.Mapper;
    
    @Mapper
    public interface DepartmentMapper extends BaseMapper<Department> {
         }

1.  测试类:

package com.itstone.mok.amooczl.treenode;
    
    import cn.hutool.core.lang.tree.Tree;
    import cn.hutool.core.lang.tree.TreeNodeConfig;
    import cn.hutool.core.lang.tree.TreeUtil;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RestController;
    import java.util.List;
    
    @RestController
    public class TreeNodeTest {
        
    
        @Autowired
        private DepartmentMapper departmentMapper;
    
        @GetMapping("/tree/node")
        public List<Tree<String>> getTreeNode() {
        
            List<Department> departments = departmentMapper.selectList(null);
    
            TreeNodeConfig treeNodeConfig = new TreeNodeConfig();
            treeNodeConfig.setIdKey("这是id");
            treeNodeConfig.setNameKey("这是name");
            treeNodeConfig.setParentIdKey("这是parentId");
            treeNodeConfig.setChildrenKey("这个children");
    
            // rootId: "0"
            return TreeUtil.build(departments, "0", treeNodeConfig, (dept, treeNode) -> {
        
                // 赋值
                treeNode.setId(dept.getDepartmentId().toString());
                treeNode.setParentId(dept.getParentDepartmentId().toString());
                treeNode.setName(dept.getDepartmentName());
                // 额外赋值
                treeNode.putExtra("dcode", dept.getDcode().toString());
            });
        }
    
    }

// 返回结果:
    [
    	{
        
    		"这是id": "1",
    		"这是parentId": "0",
    		"这是name": "股东大会",
    		"dcode": "37",
    		"这个children": [
    			{
        
    				"这是id": "2",
    				"这是parentId": "1",
    				"这是name": "董事会",
    				"dcode": "3701",
    				"这个children": [
    					{
        
    						"这是id": "3",
    						"这是parentId": "2",
    						"这是name": "秘书处",
    						"dcode": "370101",
    						"这个children": [
    							{
        
    								"这是id": "4",
    								"这是parentId": "3",
    								"这是name": "行政办公室",
    								"dcode": "37010101"
    							}
    						]
    					}
    				]
    			}
    		]
    	}
    ]

[334242d44ade4185ad1875760ee47270.png_pic_center]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/26/af0d519fb2f24db3a2610c2e1f18eb70.png