1.导入jar包
2.配置文件
a. applicationContext.xml文件
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd "> <!-- 配置数据源dataSource --> <!-- 加载配置文件 --> <context:property-placeholder location="classpath:db.properties"/> <!-- 数据库连接池 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${jdbc.driver}"/> <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> <property name="maxActive" value="10"/> <property name="maxIdle" value="5"/> </bean> <!-- 配置sqlSessionFactory --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 配置数据源 --> <property name="dataSource" ref="dataSource"/> <!-- 加载mybatis的配置文件 --> <property name="configLocation" value="classpath:SqlMapConfig.xml"/> </bean> <!-- 原始dao --> <bean id="userDao" class="com.baidu.dao.imp.UserDaoImp"> <property name="sqlSessionFactory" ref="sqlSessionFactory"/> </bean> <!-- mapper代理配置 --> <bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean"> <!-- 指定mapper接口 --> <property name="mapperInterface" value="com.baidu.dao.UserDao"/> <!-- 注入SqlSessionFactory --> <property name="sqlSessionFactory" ref="sqlSessionFactory"/> </bean> </beans>
<!-- 使用mapper扫描器创建mapper代理对象 扫描器把自动将包下边的mapper扫描出来创建代理对象在spring容器注册,bean的id为类名(首字母小写) --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 指定要扫描的包路径,如果要扫描多个包,中间使用半角逗号分隔 注意:如果使用扫描器,不需要在sqlMapConfig.xml中加载mapper,要将mapper.xml和mapper.java放在同一个目录且同名 --> <property name="basePackage" value="com.baidu.dao"/> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean>
b. SqlMapperConfig.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> <typeAliases> <typeAlias type="com.baidu.pojo.User" alias="u" /> </typeAliases> <!-- 加载mapper.xml --> <mappers> <mapper resource="UserMapper.xml" /> </mappers> </configuration>
c. XxxMaper.xml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"> <mapper namespace="com.baidu.dao.UserDao"> <!-- 查询用户通过id --> <select id="findById" parameterType="u" resultMap="u"> SELECT id,username,sex,birthday,address FROM USER <where> <if test="id!=null and id!=''"> and id = #{id} </if> <if test="username!=null and username!=''"> and username like '%${username}%' </if> </where> </select> </mapper>
d. db.propertis
jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/mybatis jdbc.username=root jdbc.password=123
3.相关类
a.UserDao.java
package com.baidu.dao; import com.baidu.pojo.User; public interface UserDao { public User findById(User u); }
b.UserDaoImp.java
package com.baidu.dao.imp; import java.util.List; import org.apache.ibatis.session.SqlSession; import org.mybatis.spring.support.SqlSessionDaoSupport; import com.baidu.dao.UserDao; import com.baidu.pojo.User; public class UserDaoImp extends SqlSessionDaoSupport implements UserDao{ @Override public User findById(User u) { //获取session // Sqlsession定义为局部变量 SqlSession sqlSession = this.getSqlSession(); User user = sqlSession.selectOne("com.baidu.dao.UserDao.findById", u); return user; } }
继承sqlSessionDaoSupport的原因是
c.User.java
public class User implements Serializable { private int id; private String username;// 用户姓名 private String sex;// 性别 private Date birthday;// 生日 private String address;// 地址 }
d.MyBatisTest.java
public class MyBatisTest { private ApplicationContext applicationContext; @Before public void setup(){ //加载spring配置文件 //取出spring的容器 applicationContext = new ClassPathXmlApplicationContext("classpath:applicationContext.xml"); } @Test public void testFindUserById() throws Exception { //从容器中取出dao UserDao userDao = (UserDao) applicationContext.getBean("userDao"); //调用dao的方法 User u=new User(); u.setUsername("fan"); User user = userDao.findById(u); System.out.println(user); } }