MyBatisPlus使用中几个需要注意的点
一、需要在pom中添加的坐标和解释二、插入时主键id的问题AUTOINPUT
三、设置显示sql日志四、代码生成器创建CodeGenerator代码生成类查看目录生成文件目录结构加载不到mapper.xml的问题-加两处配置1. pom添加2.yml文件添加
五、关于分页自定义sql使用MP的一些特性
一、需要在pom中添加的坐标和解释
<!-- MyBatisPlus包 --
>
<dependency
>
<groupId
>com.baomidou
</groupId
>
<artifactId
>mybatis-plus-boot-starter
</artifactId
>
<version
>3.3.1
</version
>
</dependency
>
<!--代码生成器，自动生成bean，service，controller，mapper--
>
<dependency
>
<groupId
>com.baomidou
</groupId
>
<artifactId
>mybatis-plus-generator
</artifactId
>
<version
>3.3.1
</version
>
</dependency
>
<!--代码生成器-默认模板引擎--
>
<dependency
>
<groupId
>org.apache.velocity
</groupId
>
<artifactId
>velocity-engine-core
</artifactId
>
<version
>2.2
</version
>
</dependency
>
<!--代码生成器-可选模板引擎--
>
<dependency
>
<groupId
>org.freemarker
</groupId
>
<artifactId
>freemarker
</artifactId
>
<version
>2.3.30
</version
>
</dependency
>
二、插入时主键id的问题
对象的主键字段需要添加如下设置
@TableId
(value
= "id",
type = IdType.AUTO
)
private Integer
id;
其中IdType的可选值为
public enum IdType
{
AUTO
(0
),//主键自增
NONE
(1
),//不为主键
INPUT
(2
),//手动输入主键
ASSIGN_ID
(3
),//分配ID，主键类型为Number
(Long和Integer
)或String
ASSIGN_UUID
(4
)//分配UUID,主键类型为String
}
AUTO
id设置成自增的时候，insert的时候就id就会被忽略，即使设置了值也无效； 返回的值可以通过getId获取插入数据的主键id值
userMapper.insert
(user
);
Integer
id = user.getId
();
INPUT
如果想要手动设置插入的id，主键类型可是设置为input，设置之后在insert的时候就必须手动 设置id值，不然就会insert失败。返回值中自然也就已经有了插入的数据id。
三、设置显示sql日志
在.yml文件中设置
mybatis-plus:
configuration:
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
四、代码生成器
需要的坐标已在一中已经说明
创建CodeGenerator代码生成类
package com.hao.springcloud.cloudproviderpayment8001.utils
;
import com.baomidou.mybatisplus.annotation.DbType
;
import com.baomidou.mybatisplus.core.exceptions.MybatisPlusException
;
import com.baomidou.mybatisplus.generator.AutoGenerator
;
import com.baomidou.mybatisplus.generator.config.DataSourceConfig
;
import com.baomidou.mybatisplus.generator.config.GlobalConfig
;
import com.baomidou.mybatisplus.generator.config.PackageConfig
;
import com.baomidou.mybatisplus.generator.config.StrategyConfig
;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy
;
import org.apache.commons.lang3.StringUtils
;
import org.springframework.stereotype.Component
;
import java.util.Scanner
;
public class CodeGenerator
{
/**
*
<p
>
* 读取控制台内容
*
</p
>
*/
public static String scanner
(String tip
) {
Scanner scanner
= new Scanner
(System.in
);
StringBuilder
help = new StringBuilder
();
help.append
("请输入" + tip +
"：");
System.out.println
(help.toString
());
if (scanner.hasNext
()) {
String ipt
= scanner.next
();
if (StringUtils.isNotEmpty
(ipt
)) {
return ipt
;
}
}
throw new MybatisPlusException
("请输入正确的" + tip +
"！");
}
public static void main
(String
[] args
) {
// 代码生成器
AutoGenerator mpg
= new AutoGenerator
();
// 全局配置 D:\springcloud2020\cloud-provider-payment8001\src\main\java\com\hao\springcloud\cloudproviderpayment8001
GlobalConfig gc
= new GlobalConfig
();
String projectPath
= "D://springcloud2020/cloud-provider-payment8001";
gc.setOutputDir
(projectPath+
"/src/main/java");
gc.setAuthor
("liguanghao");//作者
gc.setOpen
(false
);//是否打开输出目录
gc.setFileOverride
(true
);//每次生成覆盖之间的
gc.setSwagger2
(true
); //实体属性 Swagger2 注解
gc.setServiceName
("%sService");//service前面没有
"I"
gc.setBaseResultMap
(true
);//生成基本的sql语句在xml中
gc.setBaseColumnList
(true
);//生成sql片段在xml中
gc.setIdType
(IdType.AUTO
);//指定id策略，auto：主键自增
gc.setDateType
(DateType.ONLY_DATE
);//指定时间类型
mpg.setGlobalConfig
(gc
);
//包配置
PackageConfig pc
= new PackageConfig
();
//pc.setModuleName
(scanner
("模块名"));//可以手动数据模块名
pc.setParent
("com.hao.springcloud.cloudproviderpayment8001");
pc.setEntity
("bean");
pc.setController
("controller");
pc.setService
("service");
pc.setServiceImpl
("service.impl");
pc.setMapper
("mapper");
pc.setXml
("mapper.xml");
mpg.setPackageInfo
(pc
);
// 配置模板：可以配置是否生成entity、service、mapper、controller类
TemplateConfig templateConfig
= new TemplateConfig
();
templateConfig.setService
(null
);//设置不生成service类
templateConfig.setServiceImpl
(null
);//设置不生成serviceImpl类
mpg.setTemplate
(templateConfig
);
// 数据源配置
DataSourceConfig dsc
= new DataSourceConfig
();
dsc.setDbType
(DbType.MYSQL
);
dsc.setUrl
("jdbc:mysql://localhost:3306/springcloud2020?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC");
dsc.setDriverName
("com.mysql.cj.jdbc.Driver");
dsc.setUsername
("root");
dsc.setPassword
("123456");
mpg.setDataSource
(dsc
);
/*数据库表配置*/
StrategyConfig strategy
= new StrategyConfig
();
strategy.setCapitalMode
(true
);//全局大写命名
strategy.setNaming
(NamingStrategy.underline_to_camel
);//数据库表映射到实体的命名策略
strategy.setColumnNaming
(NamingStrategy.underline_to_camel
);//数据库表字段映射到实体的命名策略, 未指定按照 naming 执行
strategy.setEntityLombokModel
(true
);
strategy.setRestControllerStyle
(true
);//生成 @RestController 控制器
strategy.setInclude
(scanner
("表名，多个英文逗号分割").split
(","));
//strategy.setInclude
("area");//或者可以写死需要生成代码的表，每次修改
strategy.setControllerMappingHyphenStyle
(true
);//驼峰转连字符
//strategy.setTablePrefix
(pc.getModuleName
() +
"_");//表前缀
mpg.setStrategy
(strategy
);
mpg.execute
();
}
}
具体可查看官网文档
查看目录生成文件目录结构
加载不到mapper.xml的问题-加两处配置
由于自动生成的mapper.xml文件在java的目录下，而未在resources下，所以需要在多两处配置
1. pom添加
<resources
>
<resource
>
<directory
>src/main/java
</directory
>
<includes
>
<include
>**/*.xml
</include
>
<include
>**/*.yml
</include
>
</includes
>
</resource
>
<!--为了resources下的配置文件生效，必须把下边的也配上去--
>
<resource
>
<directory
>src/main/resources
</directory
>
<includes
>
<include
>**/*.xml
</include
>
<include
>**/*.yml
</include
>
</includes
>
</resource
>
</resources
>
2.yml文件添加
mybatis-plus:
mapper-locations: classpath:com/hao/springcloud/cloudproviderpayment8001/mapper/xml/*.xml
mapper-locations: classpath:**/mapper/xml/*.xml
五、关于分页
查询中用到分页，例如
@GetMapping
("getUserList")
public R getUserList
(String roles,int current,int size
){
QueryWrapper
<User
> queryWrapper
= new QueryWrapper
<>();
queryWrapper.like
("roles",roles
);
queryWrapper.orderByDesc
("id");//根据id倒叙排序
Page Page
= new Page
(current,size
);//分页
IPage data
= userMapper.selectPage
(Page, queryWrapper
);
return R.ok
(data
);
}
分页是不起作用的，需要添加配置:
/**
* 分页插件
*/
@Bean
public PaginationInterceptor paginationInterceptor
() {
return new PaginationInterceptor
();
}
自定义sql分页查询：https://www.jianshu.com/p/245f37f69eb9
自定义sql使用MP的一些特性
controller：
@GetMapping
("/getDoctorsByHospital")
public R
<IPage
<UserDoctor
>> getUserToken
(int current,int size,String orgId,String name
){
log.info
("分页查询集合:"+
"orgId:"+orgId+
" name:"+name+
" current:"+current+
" size:"+size
);
QueryWrapper
<UserDoctor
> queryWrapper
= new QueryWrapper
<UserDoctor
>();
Map
<String, Object
> params
= new HashMap
<String, Object
>();
String hospitalByOrgId
= hospitalUtils.getHospitalByOrgId
(orgId
);
queryWrapper.isNull
("h.id");
params.put
("u.hospital_guid", hospitalByOrgId
);
params.put
("u.status", 0
);
queryWrapper.allEq
(params
);
queryWrapper.like
(StringUtils.isNotBlank
(name
),
"u.name",name
);
queryWrapper.orderByDesc
("u.id");
IPage
<UserDoctor
> page
= new Page
<>(current,size
);
IPage
<UserDoctor
> userDoctorPage
= userDoctorMapper.selectPageByMapping
(page, queryWrapper
);
log.info
("分页查询集合返回："+userDoctorPage.getRecords
());
return R.ok
(userDoctorPage
);
}
mapper：
Page
<UserDoctor
> selectPageByMapping
(IPage page, @Param
(Constants.WRAPPER
) Wrapper
<UserDoctor
> queryWrapper
);
mapper.xml:
<select id
="selectPageByMapping" resultType
="com.bsh.ih.org.base.entity.UserDoctor" >
SELECT u.*, b.mainId AS departmentIdts
FROM
`user_doctor` u
LEFT JOIN idmapping_bt b ON u.department_id
= b.guid
LEFT JOIN idmapping_hbt h ON u.hospital_guid
= h.hospitalGuid AND u.guid
= h.guid AND h.enabled
=1
${ew.customSqlSegment}
</select
>
