MyBatis Mapper配置详解-优快云博客

本文链接：https://blog.youkuaiyun.com/u010698072/article/details/77368901

使用bubbo远程访问mybatis时，出现了点问题

自定义mapper映射文件时，必须要这么写：正确写法

  <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis/mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath*:mybatis/mapper/*.xml"/>
        <property name="typeAliasesPackage" value="com.sunwoda.pojo"/>
    </bean>

注意这段代码：

<property name="mapperLocations" value="classpath*:mybatis/mapper/*Mapper.xml"/>

如果是下面这么写：就会出错！并且是本地测试类测试时不会出错，远程调用时会出错，难以理解！错误写法（注意classpath*，这个*号不能少，少了就出错，并且完全注意不到！）
错误写法：

<property name="mapperLocations" value="classpath:mybatis/mapper/*Mapper.xml"/>

找了一个晚上，没找到原因，远程调用始终失败：

017-08-18 13:28:06,704 [DubboServerHandler-192.168.57.1:20880-thread-2] [com.alibaba.dubbo.rpc.filter.ExceptionFilter]-[ERROR]  [DUBBO] Got unchecked and undeclared exception which called by 192.168.57.1. service: 
org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): 
    at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:189)
    at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:43)
    at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:58)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:51)
    at com.sun.proxy.$Proxy21.findByExample(Unknown Source)
    at com.alibaba.dubbo.common.bytecode.Wrapper2.invokeMethod(Wrapper2.java)
    at com.alibaba.dubbo.rpc.proxy.javassist.JavassistProxyFactory$1.doInvoke(JavassistProxyFactory.java:46)
    at com.alibaba.dubbo.rpc.proxy.AbstractProxyInvoker.invoke(AbstractProxyInvoker.java:72)
    at com.alibaba.dubbo.rpc.filter.ExceptionFilter.invoke(ExceptionFilter.java:64)
    at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91)
    at com.alibaba.dubbo.rpc.filter.TimeoutFilter.invoke(TimeoutFilter.java:42)
    at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91)
    at com.alibaba.dubbo.monitor.support.MonitorFilter.invoke(MonitorFilter.java:75)
    at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91)
    at com.alibaba.dubbo.rpc.protocol.dubbo.filter.TraceFilter.invoke(TraceFilter.java:78)

源码注释提供样例：

* This is an alternative to specifying "&lt;sqlmapper&gt;" entries in an MyBatis config file.
* This property being based on Spring's resource abstraction also allows for specifying
* resource patterns here: e.g. "classpath*:sqlmap/*-mapper.xml".
*/

防不胜防！源码才是王道！