解决tk mapper 通用mapper的bug问题

如下所示：

<bean class="tk.mybatis.spring.mapper.mapperscannerconfigurer">
            <property name="basepackage" value="com.isea533.mybatis.mapper"/>
            <property name="properties">
                <value>
                    mappers=tk.mybatis.mapper.common.mapper
                </value>
            </property>
        </bean>

basepackage的属性值 不能包含通用mapper所在的包

error starting applicationcontext. to display the auto-configuration report re-run your application with 'debug' enabled.
2018-03-14 12:39:21.741 error [main] [hio-sys] o.s.boot.springapplication - application startup failed
org.springframework.beans.factory.beancreationexception: error creating bean with name 'tk.mybatis.mapper.autoconfigure.mapperautoconfiguration': invocation of init method failed; nested exception is org.springframework.beans.factory.beancreationexception: error creating bean with name 'basemapper' defined in file []: invocation of init method failed; nested exception is tk.mybatis.mapper.mapperexception: tk.mybatis.mapper.mapperexception: java.lang.classcastexception: sun.reflect.generics.reflectiveobjects.typevariableimpl cannot be cast to java.lang.class
at org.springframework.beans.factory.annotation.initdestroyannotationbeanpostprocessor.postprocessbeforeinitialization(initdestroyannotationbeanpostprocessor.java:137)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.applybeanpostprocessorsbeforeinitialization(abstractautowirecapablebeanfactory.java:409)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.initializebean(abstractautowirecapablebeanfactory.java:1620)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.docreatebean(abstractautowirecapablebeanfactory.java:555)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.createbean(abstractautowirecapablebeanfactory.java:483)
at org.springframework.beans.factory.support.abstractbeanfactory$1.getobject(abstractbeanfactory.java:306)
at org.springframework.beans.factory.support.defaultsingletonbeanregistry.getsingleton(defaultsingletonbeanregistry.java:230)
at org.springframework.beans.factory.support.abstractbeanfactory.dogetbean(abstractbeanfactory.java:302)
at org.springframework.beans.factory.support.abstractbeanfactory.getbean(abstractbeanfactory.java:197)
at org.springframework.beans.factory.support.defaultlistablebeanfactory.preinstantiatesingletons(defaultlistablebeanfactory.java:761)
at org.springframework.context.support.abstractapplicationcontext.finishbeanfactoryinitialization(abstractapplicationcontext.java:867)
at org.springframework.context.support.abstractapplicationcontext.__refresh(abstractapplicationcontext.java:543)
at org.springframework.context.support.abstractapplicationcontext.jrlockandrefresh(abstractapplicationcontext.java)
at org.springframework.context.support.abstractapplicationcontext.refresh(abstractapplicationcontext.java)
at org.springframework.boot.context.embedded.embeddedwebapplicationcontext.refresh(embeddedwebapplicationcontext.java:122)
at org.springframework.boot.springapplication.refresh(springapplication.java:693)
at org.springframework.boot.springapplication.refreshcontext(springapplication.java:360)
at org.springframework.boot.springapplication.run(springapplication.java:303)
at com.jzy.hio.hiosysapplication.main(hiosysapplication.java:35)
caused by: org.springframework.beans.factory.beancreationexception: error creating bean with name 'basemapper' defined in file [c:\users\coffee\onedrive\workspace\v2r1-hio-base\target\classes\com\jzy\hio\base\mapper\basemapper.class]: invocation of init method failed; nested exception is tk.mybatis.mapper.mapperexception: tk.mybatis.mapper.mapperexception: java.lang.classcastexception: sun.reflect.generics.reflectiveobjects.typevariableimpl cannot be cast to java.lang.class
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.initializebean(abstractautowirecapablebeanfactory.java:1628)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.docreatebean(abstractautowirecapablebeanfactory.java:555)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.createbean(abstractautowirecapablebeanfactory.java:483)
at org.springframework.beans.factory.support.abstractbeanfactory$1.getobject(abstractbeanfactory.java:306)
at org.springframework.beans.factory.support.defaultsingletonbeanregistry.getsingleton(defaultsingletonbeanregistry.java:230)
at org.springframework.beans.factory.support.abstractbeanfactory.dogetbean(abstractbeanfactory.java:302)
at org.springframework.beans.factory.support.abstractbeanfactory.getbean(abstractbeanfactory.java:202)
at org.springframework.beans.factory.support.defaultlistablebeanfactory.getbeansoftype_jrorig(defaultlistablebeanfactory.java:519)
at org.springframework.beans.factory.support.defaultlistablebeanfactory.getbeansoftype(defaultlistablebeanfactory.java)
at org.springframework.beans.factory.support.defaultlistablebeanfactory.getbeansoftype_jrorig(defaultlistablebeanfactory.java:508)
at org.springframework.beans.factory.support.defaultlistablebeanfactory.getbeansoftype(defaultlistablebeanfactory.java)
at org.springframework.context.support.abstractapplicationcontext.getbeansoftype(abstractapplicationcontext.java:1188)
at tk.mybatis.mapper.autoconfigure.mapperautoconfiguration.addpageinterceptor(mapperautoconfiguration.java:71)
at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:62)
at sun.reflect.delegatingmethodaccessorimpl.__invoke(delegatingmethodaccessorimpl.java:43)
at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java)
at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java)
at java.lang.reflect.method.invoke(method.java:498)
at org.springframework.beans.factory.annotation.initdestroyannotationbeanpostprocessor$lifecycleelement.invoke(initdestroyannotationbeanpostprocessor.java:366)
at org.springframework.beans.factory.annotation.initdestroyannotationbeanpostprocessor$lifecyclemetadata.invokeinitmethods(initdestroyannotationbeanpostprocessor.java:311)
at org.springframework.beans.factory.annotation.initdestroyannotationbeanpostprocessor.postprocessbeforeinitialization(initdestroyannotationbeanpostprocessor.java:134)
... 18 common frames omitted
caused by: tk.mybatis.mapper.mapperexception: tk.mybatis.mapper.mapperexception: java.lang.classcastexception: sun.reflect.generics.reflectiveobjects.typevariableimpl cannot be cast to java.lang.class
at tk.mybatis.mapper.mapperhelper.mapperhelper.setsqlsource(mapperhelper.java:248)
at tk.mybatis.mapper.mapperhelper.mapperhelper.processconfiguration(mapperhelper.java:311)
at tk.mybatis.spring.mapper.mapperfactorybean.checkdaoconfig(mapperfactorybean.java:54)
at org.springframework.dao.support.daosupport.afterpropertiesset(daosupport.java:44)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.invokeinitmethods(abstractautowirecapablebeanfactory.java:1687)
at org.springframework.beans.factory.support.abstractautowirecapablebeanfactory.initializebean(abstractautowirecapablebeanfactory.java:1624)
... 39 common frames omitted
caused by: tk.mybatis.mapper.mapperexception: java.lang.classcastexception: sun.reflect.generics.reflectiveobjects.typevariableimpl cannot be cast to java.lang.class
at tk.mybatis.mapper.mapperhelper.mappertemplate.setsqlsource(mappertemplate.java:258)
at tk.mybatis.mapper.mapperhelper.mapperhelper.setsqlsource(mapperhelper.java:245)
... 44 common frames omitted
caused by: java.lang.classcastexception: sun.reflect.generics.reflectiveobjects.typevariableimpl cannot be cast to java.lang.class
at tk.mybatis.mapper.mapperhelper.mappertemplate.getentityclass(mappertemplate.java:290)
at tk.mybatis.mapper.provider.base.baseselectprovider.selectone(baseselectprovider.java:50)
at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:62)
at sun.reflect.delegatingmethodaccessorimpl.__invoke(delegatingmethodaccessorimpl.java:43)
at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java)
at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java)
at java.lang.reflect.method.invoke(method.java:498)
at tk.mybatis.mapper.mapperhelper.mappertemplate.setsqlsource(mappertemplate.java:246)
... 45 common frames omitted

（通用mapper）项目升级通用mapper引发的一连串问题以及问题解决

项目环境

通用mapper版本

<dependency>
<groupid>tk.mybatis</groupid>
<artifactid>mapper-spring-boot-starter</artifactid>
<version>1.1.5</version>
</dependency>

spring boot版本

<parent>
<groupid>org.springframework.boot</groupid>
<artifactid>spring-boot-starter-parent</artifactid>
<version>1.5.9.release</version>
<relativepath />
</parent>

公司统一封装了三个核心包（kemean-aid、kemean-third、kemean-web），平时技术开发都是把三核心包下载源码到本地启动运行，这个星期把三个核心包打包成jar，让项目依赖jar启动，但启动的时候报了一个maven错误（问题一）。

问题一

caused by: java.lang.linkageerror: loader constraint violation: loader (instance of org/springframework/boot/devtools/restart/classloader/restartclassloader) previously initiated loading for a different type with name “tk/mybatis/mapper/common/mapper”

maven报了一个重复引用通用mapper jar错误，但反复查看maven引用，并没有发现有重复引用通用mapper jar包，而且项目引用源码启动是正常运行的，这个问题着实报得有点诡异！因为经验问题，重复就maven报的这个问题寻找重复引用的jar，然而处理了很久也并没有解决。后来查看通用mapper的版本maven仓库（） ，发现公司现在使用的版本已经更新好多个版本了，第一直觉认为是公司用的1.1.5这个版本有问题，于是乎升级了通用mapper版本到2版本（当前最新2.0.4），就这样掉大坑了，开始一系列的问题解决的路程。

<dependency>
<groupid>tk.mybatis</groupid>
<artifactid>mapper-spring-boot-starter</artifactid>
<version>2.0.4</version>
</dependency>

以下的问题都是在2版本的通用mapper中遇到的

问题二

tk.mybatis.mapper.mapperexception: 无法获取实体类com.kemean.bean.kemeanadminuser对应的表名!

github也有此问题的讨论：https://github.com/abel533/mybatis-spring-boot/issues/18

问题解决

修改启动类@mapperscan注解

2版本的通用mapper提供了@mapperscan注解，之前我们使用的是org.mybatis.spring.annotation.mapperscan，现需把@mapperscan改为tk.mybatis.spring.annotation.mapperscan

添加spring-devtools.properties文件

在项目src/main/resources目录新建一个文件夹meta-inf（项目右键-new-source folder），添加热部署配置文件spring-devtools.properties，在文件里面添加restart.include.companycommonlibs=tk/mybatis.*

问题三

tk.mybatis.mapper.mapperexception: tk.mybatis.mapper.provider.emptyprovider中缺少selectone方法!

github也有此问题的讨论：

https://github.com/abel533/mybatis-spring-boot/issues/92

https://github.com/abel533/mybatis-spring-boot/issues/53

问题解决：把项目热部署去掉

<dependency>
<groupid>org.springframework.boot</groupid>
<artifactid>spring-boot-devtools</artifactid>
<scope>runtime</scope>
</dependency>

在处理完问题二、三，通用mapper就升级成功了，项目也能够正常启动访问，但是，咱们在处理问题三的时候，把spring boot的热部署给去掉了，这就意味着咱们日后每改动一点，都需要重新启动部署服务，这是士可忍，叔不可忍；叔可忍，婶也不能忍的操作啊。

尝试过好多方式，都不能“升级通用mapper2版本”与“保留spring boot热部署”两个兼得，后来看到这哥们的一句话，给了我一个提醒，于是乎在刚才添加的spring-devtools.properties文件再补充一行restart.include.companycommonlibs=kemean.*

spring-devtools.properties内容（kemean.*是公司jar的前缀）

restart.include.companycommonlibs=tk/mybatis.*
restart.include.companycommonlibs=kemean.* 

https://github.com/abel533/mybatis-spring-boot/issues/53

再启动服务，服务正常使用，热部署也能够保留

问题一的最终解决

结合问题三的解决思路，那么咱们在不升级通用mapper的前提下，让项目依赖打包出来的jar运行，则仅需在

项目src/main/resources目录新建一个文件夹meta-inf（项目右键-new-source folder），添加热部署配置文件spring-devtools.properties，在文件里面添加

restart.include.companycommonlibs=kemean.* 

问题一就在不升级通用mapper下完美解决了~

以上为个人经验，希望能给大家一个参考，也希望大家多多支持www.887551.com。