简单的说一下Mybatis框架吧!!!!
首先写一个入门,直接上代码吧
1.第一点我们需要导入响应的依赖
<!--MySql的数据库驱动-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.46</version>
</dependency>
<!--Mybatis的jar包-->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.6</version>
</dependency>
<!--Mybatis依赖的日志包-->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
2.要有相对的javaBean对象
public class User {
private Integer id;
private String username;
private Date birthday;
private String sex;
private String address;
//get/set方法......
//toString方法......
}
3.在dao层创建一个接口
注意:在这边与jdbc不同的是,我们不需要去创建一个实体类去操作数据库,这边由mybatis框架来帮我们完成,我们只需要关心sql语句就好了
<?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：给哪个接口配置的映射，写接口的全限定类名-->
<mapper namespace="com.aaa.dao.UserDao">
<!--select标签：表示要执行查询语句； id：给接口里哪个方法配置的，写方法名；resultType：结果集封装类型-->
<select id="queryAll" resultType="com.itheima.bean.User">
select * from user
</select>
</mapper>
5.日志
日志也是放置在resources目录下的
# 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
# 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
6.mybatis的核心配置文件
<?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">
<!--mybatis的核心配置文件，主要配置数据库连接信息-->
<configuration>
<!--配置默认的数据库环境-->
<environments default="mysql_mybatis">
<!--定义一个数据库连接环境-->
<environment id="mysql_mybatis">
<!--设置事务管理方式，固定值JDBC-->
<transactionManager type="JDBC"/>
<!--设置数据源，POOLED，UNPOOLED，JNDI，我们使用POOLED-->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql:///mybatis"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<!-- !!!配置映射文件的位置!!!!!!!!!!!!!!这一步千万不要忘记!!!!!!!!!!!!!! -->
<mappers>
<mapper resource="com/aaa/dao/IUserDao.xml"/>
</mappers>
</configuration>