Mybatis工程升级到FlunetMybatis后引发的问题以及解决方法
0. 背景交代
为了提高开发速度,我打算将公司原有`Mybatis`框架升级为`FlunetMybatis`。可是遇到了一系列问题,下面开始爬坑
工程结构示意如下:
src/
├── main
│ ├── java.com.demo
│ │ ├── Application.java //SpringBoot启动类
│ │ ├── aop
│ │ │ └── GlobalExceptionHandler.java //全局异常处理
│ │ ├── config
│ │ │ └── FluentMybatisGenerator.java //FluentMybatis配置类
│ │ ├── controler
│ │ │ ├── CommodityController.java //新功能,使用FluentMybatis
│ │ │ └── FeedbackController.java //老功能,使用Mybatis
│ │ ├── enums
│ │ ├── mapper
│ │ │ └── FeedbackMapper.java //MybatisMapper
│ │ ├── mybatis //Mybatis拓展
│ │ │ ├── enums //枚举类
│ │ │ ├── fluent //FluentMybatis代码生成目录
│ │ │ │ ├── dao
│ │ │ │ │ ├── impl
│ │ │ │ │ │ └── CommodityDaoImpl.java //FluentMybatis生成的DAO实现
│ │ │ │ │ └── intf
│ │ │ │ │ └── CommodityDao.java //FluentMybatis生成的DAO接口
│ │ │ │ └── entity
│ │ │ │ └── CommodityEntity.java //FluentMybatis生成的数据模型
│ │ │ ├── handler
│ │ │ │ └── StringListHandler.java //自定义类型转换器(VARCHAR <==> 字符串列表)
│ │ │ └── module
│ │ │ └── StringList.java //字符串列表
│ │ ├── plugins
│ │ │ ├── files
│ │ │ └── render
│ │ ├── pojo
│ │ │ └── Feedback.java //MyBatis数据模型
│ │ ├── service
│ │ │ ├── CommodityService.java //新功能Service接口
│ │ │ ├── FeedbackService.java //老功能Service接口
│ │ │ └── impl
│ │ │ ├── CommodityServiceImpl.java //新功能Service接口实现
│ │ │ └── FeedbackServiceImpl.java //老功能Service接口实现
│ │ ├── shiro
│ │ └── utils
│ └── resources
│ ├── application-dev.yml
│ ├── application-prod.yml
│ ├── application.yml
│ ├── logback.xml
│ └── mybatis
│ ├── mapper
│ │ └── FeedbackMapper.xml //Mybatis Mapper XML文件
│ └── mybatis-config.xml
└── test└── java
主要涉及到的配置文件FluentMybatisGenerator内容:
package com.demo.config;import cn.org.atool.fluent.mybatis.spring.MapperFactory;
import cn.org.atool.generator.FileGenerator;
import cn.org.atool.generator.annotation.Column;
import cn.org.atool.generator.annotation.Table;
import cn.org.atool.generator.annotation.Tables;
import com.demo.mybatis.handler.StringListHandler;
import com.demo.mybatis.module.StringList;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;import javax.annotation.Resource;
import javax.sql.DataSource;/*** FluentMybatisConfigurer** @author adinlead* @desc* @create 2023/3/6 13:34 (星期一)*/
@Configuration
@MapperScan({"com.demo.mapper"})
public class FluentMybatisGenerator {/*** 定义fluent mybatis的MapperFactory*/@Beanpublic MapperFactory mapperFactory() {return new MapperFactory();}/*** 生成代码类*/@Tables(srcDir = "src/main/java",basePack = "com.demo.mybatis.fluent", //注意,此处生成代码的路径与原生Mybatis不在同一个包下daoDir = "src/main/java",tablePrefix = {"tb_"},tables = {@Table(value = {"tb_commodity"}, columns = {@Column(value = "create_time", insert = "now()"),@Column(value = "update_time", insert = "now()", update = "now()"),@Column(value = "cover_images", javaType = StringList.class, typeHandler = StringListHandler.class)})})static class CodeGenerator {}
}
问题以及解决
1.1 FluentMybatis无法自动生成实体类
现象:在运行后,没有在com.demo.mybatis.fluent中生成entity和dao
解决方法:
在FluentMybatisGenerator.java中,在返回自定义fluent mybatis的MapperFactory之前,执行FileGenerator.build方法:
@Resourceprivate DataSource dataSource;/*** 定义fluent mybatis的MapperFactory*/@Beanpublic MapperFactory mapperFactory() {FileGenerator.build(dataSource, CodeGenerator.class);// 引用配置类,build方法允许有多个配置类return new MapperFactory();}
mvn执行clean 后 再次运行项目即可

效果如下

1.2 自定义SqlSessionFactoryBean导致的一系列问题
官方WIKI-环境部署-简单示例中看到了如下代码:
@Configuration
@MapperScan({"你的Mapper package"})
public class ApplicationConfig {@Bean("dataSource")@Beanpublic DataSource newDataSource() {// TODO}@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {SqlSessionFactoryBean bean = new SqlSessionFactoryBean();bean.setDataSource(newDataSource());ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();// 以下部分根据自己的实际情况配置// 如果有mybatis原生文件, 请在这里加载bean.setMapperLocations(resolver.getResources("classpath*:mapper/*.xml"));org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();configuration.setLazyLoadingEnabled(true);configuration.setMapUnderscoreToCamelCase(true);bean.setConfiguration(configuration);return bean;}// 定义fluent mybatis的MapperFactory@Beanpublic MapperFactory mapperFactory() {return new MapperFactory();}
}
在此示例中,作者重定义了SqlSessionFactoryBean,但是如果你没能正确配置,那么这一行为也会导致一系列错误。
1.2.1 Spring无法找到需要注入的对象
错误如下:
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2023-03-08 13:17:02 [main] ERROR o.s.b.d.LoggingFailureAnalysisReporter - ***************************
APPLICATION FAILED TO START
***************************Description:A component required a bean of type 'com.demo.mybatis.fluent.mapper.CommodityMapper' that could not be found.Action:Consider defining a bean of type 'com.demo.mybatis.fluent.mapper.CommodityMapper' in your configuration.
这个一般是Spring 进行DI时,找不到FluentMybatis的Mapper引起的错误,原因在于官方文档中要求你在@MapperScan中添加MybatisMapper包路径,但是如果你的MybatisMapper和FluentMybatisMapper不在一个包中时,也需要把FluentMybatis生成的Mapper路径也添加到扫描器中,或者干脆放大扫描范围。
添加FluentMybatisMapper包路径(推荐)
@Configuration
@MapperScan({"com.demo.mapper", "com.demo.mybatis.fluent.mapper"})
public class FluentMybatisGenerator {...
}
扩大扫描范围
@Configuration
@MapperScan({"com.demo"})
public class FluentMybatisGenerator {...
}
1.2.2 原MybatisMapper报BindingException错误
调用原生MybatisMapper中的方法时,提示无法映射到方法,错误信息如下:
org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.demo.mapper.FeedbackMapper.countManagerRecordsat org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:235)at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:53)at org.apache.ibatis.binding.MapperProxy.lambda$cachedInvoker$0(MapperProxy.java:115)at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)at org.apache.ibatis.binding.MapperProxy.cachedInvoker(MapperProxy.java:102)at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)at com.sun.proxy.$Proxy93.countManagerRecords(Unknown Source)at com.demo.service.impl.FeedbackServiceImpl.getManagerFeedbacks(FeedbackServiceImpl.java:77)at com.demo.controler.FeedbackController.getAdminRecords(FeedbackController.java:74)at com.demo.controler.FeedbackController$$FastClassBySpringCGLIB$$80abedc3.invoke(<generated>)
这个错误一般是由于你没有正确配置MyBatis XML文件路径导致的,需要在自定义SqlSessionFactoryBean方法中修改XML文件扫描路径:
@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {SqlSessionFactoryBean bean = new SqlSessionFactoryBean();bean.setDataSource(dataSource);ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();/* 注意!在这里需要将原生Mybatis的XML路径写到配置中 */bean.setMapperLocations(resolver.getResources("classpath*:mybatis/mapper/*.xml"));org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();configuration.setLazyLoadingEnabled(true);configuration.setMapUnderscoreToCamelCase(true);bean.setConfiguration(configuration);return bean;}
1.2.3 Mybatis别名解析错误
在修改完1.2.2问题后,你大概率会碰到这个问题,具体表现为:
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'shiroFilter' defined in class path resource [com/demo/shiro/ShiroConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.shiro.spring.web.ShiroFilterFactoryBean]: Factory method 'shiroFilterFactoryBean' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'securityManager' defined in class path resource [com/demo/shiro/ShiroConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.shiro.web.mgt.DefaultWebSecurityManager]: Factory method 'securityManager' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'shiroRealm': Unsatisfied dependency expressed through field 'userService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [xxxx/DemoProject/target/classes/com/demo/mapper/UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactoryBean' defined in class path resource [com/demo/config/FluentMybatisGenerator.class]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [xxxx/DemoProject/target/classes/mybatis/mapper/FeedbackMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [xxxx/DemoProject/target/classes/mybatis/mapper/FeedbackMapper.xml]'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Feedback'. Cause: java.lang.ClassNotFoundException: Cannot find class: Feedbackat org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:658)at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:486)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1352)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1195)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:213)at org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:270)at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:762)at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:567)at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145)at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754)at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:434)at org.springframework.boot.SpringApplication.run(SpringApplication.java:338)at org.springframework.boot.SpringApplication.run(SpringApplication.java:1343)at org.springframework.boot.SpringApplication.run(SpringApplication.java:1332)at com.demo.Application.main(NewCommunity.java:27)
根本原因在MyBatis中:
Caused by: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [xxxx/DemoProject/target/classes/mybatis/mapper/FeedbackMapper.xml]'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Feedback'. Cause: java.lang.ClassNotFoundException: Cannot find class: Feedbackat org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:123)at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:95)at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:611)... 92 common frames omitted
Caused by: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Feedback'. Cause: java.lang.ClassNotFoundException: Cannot find class: Feedbackat org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:118)at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:263)at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:254)at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElements(XMLMapperBuilder.java:246)at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:119)... 94 common frames omitted
Caused by: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Feedback'. Cause: java.lang.ClassNotFoundException: Cannot find class: Feedbackat org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:120)at org.apache.ibatis.builder.BaseBuilder.resolveAlias(BaseBuilder.java:149)at org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:116)... 98 common frames omitted
Caused by: java.lang.ClassNotFoundException: Cannot find class: Feedbackat org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:196)at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:89)at org.apache.ibatis.io.Resources.classForName(Resources.java:261)at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:116)... 100 common frames omitted
据我猜测,其原因在于FluentMybatis没有夹在原生Mybatis的实体类,解决方法很简单,在自定义SqlSessionFactoryBean的方法中,手动添加原生MyBatis实体类所在包即可:
@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {SqlSessionFactoryBean bean = new SqlSessionFactoryBean();bean.setDataSource(dataSource);ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();/* 注意!在这里需要将原生Mybatis的XML路径写到配置中 */bean.setMapperLocations(resolver.getResources("classpath*:mybatis/mapper/*.xml"));org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();configuration.setLazyLoadingEnabled(true);configuration.setMapUnderscoreToCamelCase(true);/* 注意!在这里需要将原生MyBatis的实体类包名添加到TypeAliasRegistry中 */configuration.getTypeAliasRegistry().registerAliases("com.demo.pojo");bean.setConfiguration(configuration);return bean;}
1.2.0 一割解千愁
经过测试,其实不需要自定义SqlSessionFactoryBean也可以正常的将原生MyBatis和FluentMybatis二者结合使用,所以如果上面的方法不能解决问题时,可以尝试将自定义SqlSessionFactoryBean方法删除后再试。
3. 完整的FluentMybatisGenerator.java:
package com.demo.config;import cn.org.atool.fluent.mybatis.spring.MapperFactory;
import cn.org.atool.generator.FileGenerator;
import cn.org.atool.generator.annotation.Column;
import cn.org.atool.generator.annotation.Table;
import cn.org.atool.generator.annotation.Tables;
import com.demo.mybatis.handler.StringListHandler;
import com.demo.mybatis.module.StringList;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;import javax.annotation.Resource;
import javax.sql.DataSource;/*** FluentMybatisConfigurer** @author adinlead* @desc* @create 2023/3/6 13:34 (星期一)*/
@Configuration
public class FluentMybatisGenerator {/*** 从Spring中获取DataSource*/@Resourceprivate DataSource dataSource;/*** 使用定义Fluent Mybatis的MapperFactory*/@Beanpublic MapperFactory mapperFactory() {/* 引用配置类,build方法允许有多个配置类 */FileGenerator.build(dataSource, CodeGenerator.class);return new MapperFactory();}/*** 使用自定义SqlSessionFactoryBean* @return* @throws Exception*/@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean() throws Exception {SqlSessionFactoryBean bean = new SqlSessionFactoryBean();bean.setDataSource(dataSource);ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();/* 注意!在这里需要将原生Mybatis的XML路径写到配置中 */bean.setMapperLocations(resolver.getResources("classpath*:mybatis/mapper/*.xml"));org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();configuration.setLazyLoadingEnabled(true);configuration.setMapUnderscoreToCamelCase(true);/* 注意!在这里需要将原生Mybatis的XML路径写到配置中 */configuration.getTypeAliasRegistry().registerAliases("com.demo.pojo");bean.setConfiguration(configuration);return bean;}/*** 生成代码类*/@Tables(srcDir = "src/main/java",basePack = "com.demo.mybatis.fluent",daoDir = "src/main/java",tablePrefix = {"tb_"},tables = {@Table(value = {"tb_commodity"}, columns = {@Column(value = "create_time", insert = "now()"),@Column(value = "update_time", insert = "now()", update = "now()"),@Column(value = "cover_images", javaType = StringList.class, typeHandler = StringListHandler.class)})})static class CodeGenerator {}
}