Java研学-数据字典(一)

一需求分析

1 分析

在项目中会有很多的下拉框，这些下拉框的特点，就是以键值对的形式存在，其中 value（如 id：1，2… ），key（展示给用户的内容），数据库中可通过 value 寻找对应的 key，对于固定的内容可使用数据字典形式进行填写，防止出错。
实现方案：
1.直接硬编码写在html代码中（升级复杂，维护困难）
2.为每个下拉框都设计一个表，然后提供CRUD功能（表单中下拉框很多，内容相似，没必要每个都配，只特殊情况下使用）
3.使用数据字典的方式（维护项目中所有的下拉列表）

二表设计

1 概述

sys_dict_type 中主要存储项目中有哪些下拉框，sys_dict_data 中主要存储项目中下拉框对应的option的具体内容，两张表通过 dict_type 进行关联，查询时可通过下拉框名称“性别”于 sys_dict_type 表中搜索 dict_name 为“性别”的记录的 dict_type 字段，通过该字段到 sys_dict_data 表中获取需要展示的 key（dict_value）与 value（dict_label），通过 dict_sort 可对下拉框中内容进行排序，如：
在这里插入图片描述

2 字典类型表 sys_dict_type

所有程序中的select，该表中 dict_type 需唯一

字段	描述
dict_id	主键
dict_name	字典名称（例：性别）
dict_type	字典类型（例：sex）
remark	备注（例：性别）

3 字典数据表 sys_dict_data

所有程序中的select所对应的option，例：< option value=“1”>女< /option>，其中键值为1，标签为女

字段	描述
dict_code	主键
dict_type	字典类型
dict_label	字典标签（例：女）
dict_value	字典键值（例：1）
dict_sort	字典排序（对下拉列表数据进行排序）
remark	备注

4 客户表 t_customer

客户表中存储 source_value 与 school_value 通过关联上表，获取所需的数据，建议使用左连接防止由于字段NULL时查询丢失数据

字段	描述
id	主键
name	客户名称
phone	联系方式
source_value	常住地
school_value	最高学历

三项目搭建

1 pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.tj</groupId>
    <artifactId>sys-dict-demo</artifactId>
    <version>1.0.0</version>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.13.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <druid.version>1.2.6</druid.version>
        <mybatis-spring-boot.version>2.1.4</mybatis-spring-boot.version>
        <fastjson.version>1.2.76</fastjson.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- SpringBoot集成thymeleaf模板 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <!--阿里数据库连接池 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>${druid.version}</version>
        </dependency>
        <!-- SpringBoot集成mybatis框架 -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis-spring-boot.version}</version>
        </dependency>
        <!-- Mysql驱动包 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!-- spring-boot-devtools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional> <!-- 表示依赖不会传递 -->
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <scope>provided</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <!-- MyBatis 逆向工程插件 -->
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.2</version>
                <configuration>
                    <verbose>true</verbose>
                    <overwrite>false</overwrite>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <version>5.1.45</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>
</project>

2 主启动类 – SysDictApp

@SpringBootApplication
// mapper包不在同一目录下，填写路径（所有mapper接口）
@MapperScan("cn.tj.**.mapper")
public class SysDictApp {
    public static void main(String[] args) {
        SpringApplication.run(SysDictApp.class,args);
    }
}

3 yml配置文件 – application.yml

# Spring配置
spring:
  # 模板引擎
  thymeleaf:
    mode: HTML
    encoding: utf-8
    # 禁用缓存
    cache: false
  # 数据库配置信息
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/zd?serverTimezone=GMT%2B8
    username: root
    password: root
# MyBatis
mybatis:
  # 配置mapper的扫描，找到所有的mapper.xml映射文件
  mapperLocations: classpath*:mapper/*Mapper.xml
# 日志配置
logging:
  level:
    cn.tj: debug
    org.springframework: warn
server:
  port: 80

4 实体类 – SysDictType

@Getter
@Setter
public class SysDictType{
    private Long dictId;
    private String dictName;
    private String dictType;
    private String remark;
}

5 实体类 – SysDictData

@Getter
@Setter
public class SysDictData {
    private Long dict_code;
    private Integer dict_sort;
    private String dict_label;
    private String dict_value;
    private String dict_type;
    private String remark;
}

6 实体类 – Customer

@Setter
@Getter
public class Customer {
    private Long id;
    private String name;
    private String phone;
    // 关联字段
    private SysDictData sourceType;
    private SysDictData schoolType;
}

7 数据库表 – sys_dict_type

CREATE TABLE `sys_dict_type` (
  `dict_id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '字典主键',
  `dict_name` varchar(100) DEFAULT '' COMMENT '字典名称',
  `dict_type` varchar(100) DEFAULT '' COMMENT '字典类型',
  `remark` varchar(500) DEFAULT NULL COMMENT '备注',
  PRIMARY KEY (`dict_id`),
  UNIQUE KEY `dict_type` (`dict_type`)
) ENGINE=InnoDB AUTO_INCREMENT=22 DEFAULT CHARSET=utf8 COMMENT='字典类型表';

8 数据库表 – sys_dict_data

CREATE TABLE `sys_dict_data` (
  `dict_code` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '字典编码',
  `dict_sort` int(4) DEFAULT '0' COMMENT '字典排序',
  `dict_label` varchar(100) DEFAULT '' COMMENT '字典标签',
  `dict_value` varchar(100) DEFAULT '' COMMENT '字典键值',
  `dict_type` varchar(100) DEFAULT '' COMMENT '字典类型',
  `remark` varchar(500) DEFAULT NULL COMMENT '备注',
  PRIMARY KEY (`dict_code`)
) ENGINE=InnoDB AUTO_INCREMENT=67 DEFAULT CHARSET=utf8 COMMENT='字典数据表';

9 数据库表 – t_customer

CREATE TABLE `t_customer` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  `phone` varchar(255) DEFAULT NULL,
  `source_value` bigint(20) DEFAULT NULL,
  `school_value` bigint(20) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;

10 mapper接口 – SysDictTypeMapper

public interface SysDictTypeMapper {
    List<SysDictType> selectAll();
    int getCountByDictType(String dictType);
    void insert(SysDictType sysDictType);
    SysDictType get(Long dictId);
    void update(SysDictType sysDictType);
    SysDictType getByDictType(String dictType);
}

11 mapper接口 – SysDictDataMapper

public interface SysDictDataMapper {
    int deleteByPrimaryKey(Long dict_code);
    int insert(SysDictData record);
    SysDictData selectByPrimaryKey(Long dict_code);
    List<SysDictData> selectAll();
    int updateByPrimaryKey(SysDictData record);
    List<SysDictData> queryByDictType(String dictType);
}

12 mapper接口 – CustomerMapper

public interface CustomerMapper {
    List<Customer> selectAll();
    void insert(Customer customer);
    void update(Customer customer);
    Customer get(Long id);
}

13 mapper.xml – SysDictTypeMapper

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.tj.mapper.SysDictTypeMapper">
    <resultMap id="sysDictTypeResult" type="cn.tj.domain.SysDictType">
        <result column="dict_id" property="dictId"/>
        <result column="dict_name" property="dictName"/>
        <result column="dict_type" property="dictType"/>
        <result column="remark" property="remark"/>
    </resultMap>
    <insert id="insert" keyProperty="dictId" useGeneratedKeys="true">
        insert into sys_dict_type(dict_name, dict_type, remark) values (#{dictName},#{dictType},#{remark})
    </insert>
    <update id="update">
        update sys_dict_type set
            dict_name = #{dictName},
            remark = #{remark}
            where dict_id = #{dictId}
    </update>
    <select id="selectAll" resultMap="sysDictTypeResult">
        select dict_id, dict_name, dict_type, remark  from sys_dict_type
    </select>
    <select id="getCountByDictType" resultType="java.lang.Integer">
        select count(*) from sys_dict_type where dict_type=#{dictType}
    </select>
    <select id="get" resultMap="sysDictTypeResult">
        select dict_id, dict_name, dict_type, remark  from sys_dict_type
        where dict_id=#{dictId}
    </select>
    <select id="getByDictType" resultMap="sysDictTypeResult">
        select dict_id, dict_name, dict_type, remark  from sys_dict_type
        where dict_type=#{dictType}
    </select>
</mapper>

14 mapper.xml – SysDictDataMapper

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="cn.tj.mapper.SysDictDataMapper" >
  <resultMap id="BaseResultMap" type="cn.tj.domain.SysDictData" >
    <id column="dict_code" property="dict_code" />
    <result column="dict_sort" property="dict_sort" />
    <result column="dict_label" property="dict_label" />
    <result column="dict_value" property="dict_value" />
    <result column="dict_type" property="dict_type" />
    <result column="remark" property="remark" />
  </resultMap>
  <delete id="deleteByPrimaryKey" >
    delete from sys_dict_data
    where dict_code = #{dict_code}
  </delete>
  <insert id="insert" >
    insert into sys_dict_data (dict_code, dict_sort, dict_label, dict_value, dict_type, remark
      )
    values (#{dict_code}, #{dict_sort}, #{dict_label}, #{dict_value}, #{dict_type}, #{remark}
      )
  </insert>
  <update id="updateByPrimaryKey" >
    update sys_dict_data
    set dict_sort = #{dict_sort},
      dict_label = #{dict_label},
      dict_value = #{dict_value},
      remark = #{remark}
    where dict_code = #{dict_code}
  </update>
  <select id="selectByPrimaryKey" resultMap="BaseResultMap" >
    select dict_code, dict_sort, dict_label, dict_value, dict_type, remark
    from sys_dict_data
    where dict_code = #{dict_code}
  </select>
  <select id="selectAll" resultMap="BaseResultMap" >
    select dict_code, dict_sort, dict_label, dict_value, dict_type, remark
    from sys_dict_data
  </select>
  <select id="queryByDictType" resultMap="BaseResultMap">
    select dict_code, dict_sort, dict_label, dict_value, dict_type, remark
    from sys_dict_data
    where dict_type=#{dictType}
    order by dict_sort asc
  </select>
</mapper>

15 mapper.xml – CustomerMapper

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.tj.mapper.CustomerMapper">
    <resultMap id="CustomerResult" type="cn.tj.domain.Customer">
        <result column="id" property="id"/>
        <result column="name" property="name"/>
        <result column="phone" property="phone"/>
        <result column="s1_label" property="sourceType.dict_label"/>
        <result column="s2_label" property="schoolType.dict_label"/>
        <result column="s1_value" property="sourceType.dict_value"/>
        <result column="s2_value" property="schoolType.dict_value"/>
    </resultMap>
    <select id="selectAll" resultMap="CustomerResult">
        select c.id,c.name,c.phone,s1.dict_value s1_value,s1.dict_label s1_label,s2.dict_value s2_value,s2.dict_label s2_label from t_customer c
        left join sys_dict_data s1 on (c.source_value = s1.dict_value and s1.dict_type="sourceType")
        left join sys_dict_data s2 on (c.school_value = s2.dict_value and s2.dict_type="schoolType")
    </select>
    <insert id="insert">
        insert into t_customer(name,phone,source_value,school_value)
        values (#{name},#{phone},#{sourceType.dict_value},#{schoolType.dict_value})
    </insert>
    <update id="update">
        update t_customer set
        name = #{name},
        phone = #{phone},
        source_value = #{sourceType.dict_value},
        school_value = #{schoolType.dict_value}
        where id  = #{id}
    </update>
    <select id="get" resultMap="CustomerResult">
        select c.id,c.name,c.phone,s1.dict_value s1_value,s1.dict_label s1_label,s2.dict_value s2_value,s2.dict_label s2_label from t_customer c
        left join sys_dict_data s1 on (c.source_value = s1.dict_value and s1.dict_type="sourceType")
        left join sys_dict_data s2 on (c.school_value = s2.dict_value and s2.dict_type="schoolType")
        where id = #{id}
    </select>
</mapper>