Spring Boot + Nuxt + Debian（五）：spring boot + mybatis + mysql业务逻辑

前言

本文记录后端的业务流程

一、本项目持久层框架为mybatis（version：1.3.5）

        <dependency><groupId>org.mybatis.generator</groupId><artifactId>mybatis-generator-core</artifactId><version>${mybatis-generator.version}</version></dependency>

generatorConfig.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN""http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd" >
<generatorConfiguration><classPathEntrylocation="D:\software\SoftEnviron\apache-maven-3.6.1\maven-repository\mysql\mysql-connector-java\8.0.17\mysql-connector-java-8.0.17.jar"/><context id="context"><commentGenerator><!-- 是否去除自动生成的注释 true：是 ： false:否 --><property name="suppressAllComments" value="true"/></commentGenerator><jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"connectionURL="jdbc:mysql://localhost:3308/evaluate?useUnicode=true&amp;characterEncoding=utf8&amp;serverTimezone=GMT"userId="root" password="root"><!-- 加入此注解保证只生成自己需要的User类 --><property name="nullCatalogMeansCurrent" value="true"/></jdbcConnection><!-- 类型转换 --><javaTypeResolver><!--默认false，把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer true，把JDBC DECIMAL和 NUMERIC 类型解析为java.math.BigDecimal --><property name="forceBigDecimals" value="false"/></javaTypeResolver><javaModelGenerator targetPackage="com.zq.evaluate.entity" targetProject="MAVEN"/><sqlMapGenerator targetPackage="com.zq.evaluate.entity" targetProject="MAVEN"/><javaClientGenerator targetPackage="com.zq.evaluate.repository" targetProject="MAVEN" type="XMLMAPPER"/><table tableName="user" domainObjectName="UserEntity" mapperName="UserRepository" schema="evaluate"><generatedKey column="id" sqlStatement="JDBC"/></table><table tableName="permission" domainObjectName="PermissionEntity" mapperName="PermissionRepository" schema="evaluate"><generatedKey column="id" sqlStatement="JDBC"/></table><table tableName="role" domainObjectName="RoleEntity" mapperName="RoleRepository" schema="evaluate"><generatedKey column="id" sqlStatement="JDBC"/></table></context>
</generatorConfiguration>

二、数据库为MySQL，贴几条我用到的命令

①mysql唯一约束性

查看：

SHOW KEYS FROM 数据表;

增加 ：

ALTER TABLE 数据表 ADD UNIQUE(字段名); 

删除 ：

ALTER TABLE 数据表 DROP IND;

②某字段等于行数

SET @num=0;
UPDATE 数据表 SET 字段=(@num:=@num+1)

③给自增ID重设起始值

ALTER TABLE 数据表 auto_increment = 1;

注：oracle设置自增

①oracle序列查询

select * from user_sequences where sequence_name = 'SEQ_数据表';

②创建序列，索引

create sequence SEQ_数据表
minvalue 100000
maxvalue 999999
start with 100000
increment by 1
cache 2  --设置缓存cache个序列，如果系统down掉了或者其它情况将会导致序列不连续，也可以设置为---NOCACHE防止跳号
cycle;  --循环,当达到最大值时,不是从start with设置的值开始循环。而是从1开始循环

③使用

INSERT INTO 数据表(ID) VALUES(SEQ_数据表.NEXTVAL);

三、表结构设计及项目配置完成，执行mybatis-generator:generate

1.xml文件位置：在repository/src/main/resources下新建mybatis文件夹

2.entity及entityExample放到java/com/././entity下，无需更改

四.数据访问层

1.重复型管理——泛型

/*** @author *** @date Dec. 31, 2019* @description mybatis基础接口，所有repository接口均继承该接口*/
public interface MybatisBaseRepository<T, PK extends Serializable, E> {long countByExample(E example);int deleteByExample(E example);int deleteByPrimaryKey(PK id);int insert(T record);int insertSelective(T record);List<T> selectByExample(E example);T selectByPrimaryKey(PK id);int updateByExampleSelective(@Param("record") T record, @Param("example") E example);int updateByExample(@Param("record") T record, @Param("example") E example);int updateByPrimaryKeySelective(T record);int updateByPrimaryKey(T record);int logicalDeletion(String code);int batchLogicalDeletion(@Param("codeList") List<String> codeList);int batchDelete(@Param("codeList") List<String> codeList);
}

2.CollegeRepository 对应4.3

@Repository
public interface CollegeRepository extends MybatisBaseRepository<CollegeEntity, Integer, CollegeEntityExample> {int batchInsert(@Param("insertList") List<CollegeBO> collegeBOList);List<CollegeBO> selectByCondition(@Param("collegeBO") CollegeBO collegeBO);
}

3.CollegeRepository.xml对应4.2

<?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="com.zq.evaluate.repository.CollegeRepository"><update id="logicalDeletion">UPDATE collegeSET STATUS = ABS( STATUS - 1 )WHEREcode = #{code}</update><update id="batchLogicalDeletion" parameterType="list">UPDATE collegeSET STATUS = ABS( STATUS -1 )WHERE<foreach collection="codeList" index="index" item="cl" separator="or">code = #{cl}</foreach></update><delete id="batchDelete" parameterType="list">DELETE FROM college WHERE<foreach collection="codeList" index="index" item="cl" separator="or">code = #{cl}</foreach></delete><insert id="batchInsert" parameterType="list">INSERT INTO college ( code, name )VALUES<foreach collection="insertList" index="index" item="sbl" separator=",">( #{sbl.code}, #{sbl.name} )</foreach></insert><select id="selectByCondition" resultType="com.zq.evaluate.common.bo.college.CollegeBO">SELECT*FROMcollege<where><if test="collegeBO!=null"><if test="collegeBO.code!=null and collegeBO.code!=''">AND code = #{collegeBO.code}</if><if test="collegeBO.name!=null and collegeBO.name!=''">AND name like CONCAT('%',#{collegeBO.name},'%')</if></if></where></select>
</mapper>

五、业务层(小型快速开发故没有使用serviceImpl)

/*** @author *** @date Jan. 03, 2020* @description 学院业务层*/
@Service
public class CollegeService extends CrudBaseService<CollegeRepository, CollegeEntity, Integer, CollegeEntityExample> {/*** @return int* @author *** @date Jan. 06, 2020* @Param collegeBOList* @description 批量添加*/public int batchInsert(List<CollegeBO> collegeBOList) {return dao.batchInsert(collegeBOList);}/*** @return list* @author *** @date Jan. 07, 2020* @Param collegeBO* @description 根据条件查询学院*/public List<CollegeBO> select(CollegeBO collegeBO) {logger.info("查询学院");return dao.selectByCondition(collegeBO);}
}

六、总结