一、簡介：mybatis是支持屬性使用駝峰的命名

如下java代碼

public class Role {
    private Integer id;
    private String roleName;
    private String roleKey;
    private Integer orderNum;
    private Integer roleType;
    private String remark;
    ...省略set,get方法
}

列名是有下劃線的

像上面這樣設計是需要配置下劃線與駝峰式命名規(guī)則的映射

mapUnderscoreToCamelCase：是否啟用下劃線與駝峰式命名規(guī)則的映射（如first_name => firstName）

 <setting name="mapUnderscoreToCamelCase" value="true"/>

二、在SSM整合中的配置

方式一:
在applicationContext-dao.xml中引入mybatis配置

<!-- 配置sqlSessionFactory -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <!-- 數(shù)據(jù)庫連接池 -->
    <property name="dataSource" ref="dataSource"/>
    <!-- 加載Mybatis全局配置文件 -->
    <property name="configLocation" value="/WEB-INF/classes/mybatis/SqlMapConfig.xml"/>
</bean>

SqlMapConfig.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--配置全局屬性-->
    <settings>
        <!--開啟駝峰命名轉(zhuǎn)換-->
       <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>

方式二:
在applicationContext-dao.xml中直接配置

<bean class="org.mybatis.spring.SqlSessionFactoryBean" id="factory">
    <property name="dataSource" ref="dataSource"/>
    <property name="typeAliasesPackage" value="com.glc.domain"/>
    
    <property name="configuration">
        <bean class="org.apache.ibatis.session.Configuration">
            <property name="mapUnderscoreToCamelCase" value="true"/>
        </bean>
    </property>

</bean>

三、親測代碼配置文件spring-mybatis.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx.xsd">

    <!-- 掃描service包下所有使用注解的類型 -->
    <context:component-scan base-package="com.chatRobot.service"/>

    <!-- 配置數(shù)據(jù)庫相關參數(shù)properties的屬性：${url} -->
    <context:property-placeholder location="classpath:jdbc.properties"/>

    <!-- 數(shù)據(jù)庫連接池 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="maxPoolSize" value="${c3p0.maxPoolSize}"/>
        <property name="minPoolSize" value="${c3p0.minPoolSize}"/>
        <property name="autoCommitOnClose" value="${c3p0.autoCommitOnClose}"/>
        <property name="checkoutTimeout" value="${c3p0.checkoutTimeout}"/>
        <property name="acquireRetryAttempts" value="${c3p0.acquireRetryAttempts}"/>
    </bean>

    <!-- 配置SqlSessionFactory對象 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 注入數(shù)據(jù)庫連接池 -->
        <property name="dataSource" ref="dataSource"/>
        <!-- 掃描model包 使用別名 -->
        <property name="typeAliasesPackage" value="com.chatRobot.model"/>
        <!-- 掃描sql配置文件:mapper需要的xml文件 -->
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>

        <property name="configuration">
            <bean class="org.apache.ibatis.session.Configuration">
                <!--mybatis支持屬性使用駝峰的命名-->
                <property name="mapUnderscoreToCamelCase" value="true"/>
            </bean>
        </property>
    </bean>

    <!-- 配置掃描Dao接口包，動態(tài)實現(xiàn)Dao接口，注入到spring容器中 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 注入sqlSessionFactory -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!-- 給出需要掃描Dao接口包 -->
        <property name="basePackage" value="com.chatRobot.dao"/>
    </bean>

    <!-- 配置事務管理器 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!-- 注入數(shù)據(jù)庫連接池 -->
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!-- 配置基于注解的聲明式事務 -->
    <tx:annotation-driven transaction-manager="transactionManager"/>

</beans>