mybatis入门案例（基于xml）

以user实体类为例搭建一个入门案例（基于xml配置）

1、 mybatis所需依赖

	<dependencies>
		<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!-- log4j日志，可添加可不添加-->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <!--        Junit测试-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
            <scope>test</scope>
        </dependency>
       </dependencies>
       <!--    如果你的xml映射文件放在的dao中，由于项目默认只扫描resources下的xml文件，所以需要以下语句-->
        <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
        </resources>
    </build>

2、 在resource里面创建xml配置文件

<?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>
    <!--    配置环境-->
    <environments default="mysql">
        <!--        配置mysql的环境-->
        <environment id="mysql">
            <!--            配置事务的类型-->
            <transactionManager type="JDBC"></transactionManager>
            <!--            配置数据源（连接池）-->
            <dataSource type="POOLED">
                <!--            配置连接数据库的四个基本信息-->
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <!--            用的mysql5以后的驱动请加上时区-->
                <property name="url" value="jdbc:mysql:///eesy"/>
                <property name="username" value="root"/>
                <property name="password" value="962464"/>
            </dataSource>
        </environment>
    </environments>
    <!--    指定映射配置文件，映射配置文件指的是每个dao独立的配置文件-->
    <mappers>
        <mapper resource="com/lp/dao/UserDao.xml"/>
    </mappers>
</configuration> 

3、 在dao（mapper）中创建mapper的UserDao.xml映射文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!--namespace名称必须是dao的全限定类名-->
<mapper namespace="com.lp.dao.UserDao" resultType="com.lp.domain.User">
    <!--    配置查询所有,id必须要与接口一致-->
    <select id="getAll">
        select * from user;
    </select>
</mapper>

4、log4j日志log4j.properties文件

# Set root category priority to INFO and its only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE            debug   info   warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE

# Set the enterprise logger category to FATAL and its only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE

# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n