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后端框架学习-----mybatis(使用mybatis框架遇到的问题)

1、配置文件没有注册(解决:在核心配置文件中注册mapper,注册有三种形式。资源路径用斜杆,包和类用点)

<mappers>
        <!--每一个mapper.xml文件都需要在mybatis核心配置文件中被注册-->
        <mapper resource="com/zheng/Dao/UserMapper.xml"></mapper>

    </mappers>      

2、绑定接口错误(解决:在mapper.xml文件中,namespace是要实现的接口类)

<mapper namespace="com.zheng.Dao.UserMapper">      

3、方法名不对(解决:id是接口中对应的方法名)

<select id="selectAllUser" resultType="com.zheng.pojo.User">
        select * from mybatis.user
    </select>      

4、返回类型不对

<select id="selectAllUser" resultType="com.zheng.pojo.User">
        select * from mybatis.user
    </select>      

5、maven导出资源出问题

<!--在build中配置resources,来防止我们资源导出失败的问题-->
    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>      
serverTimezone=Asia/Shanghai"      

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