整合思路
- SqlSessionFactory對象放入spring容器中作爲單例實例存在
- mapper代理開發中,直接從spring容器中獲得mapper的代理對象。
- 數據庫的連接方式,數據庫連接池,事物管理都交給spring容器來管理
- 傳統的dao開發,從spring容器中獲得sqlsession對象
整合步驟
導包
spring包(包括了SpringMvc)
mybatis包
數據庫驅動和連接池包
mybatis核心和spring整合包
- 編寫SqlMapConfig.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>
<!-- 設置別名 -->
<typeAliases>
<!-- 2. 指定掃描包,會把包內所有的類都設置別名,別名的名稱就是類名,大小寫不敏感 -->
<package name="cn.itcast.mybatis.pojo" />
</typeAliases>
<!-- 引入mapper配置文件和接口的位置 -->
<mappers>
<package name="cn.itcast.mybatis.mapper"/>
</mappers>
</configuration>
- 數據庫連接配置文件
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8
jdbc.username=root
jdbc.password=root
- log4j文件
# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
- applicationContext.xml配置文件
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">
<!-- 加載配置文件 -->
<context:property-placeholder location="classpath:db.properties" />
<!-- 數據庫連接池 -->
<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,產生SqlSessionFactory對象需要注入 dataSource數據源,和加載SqlMapConfig配置文件-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 配置數據源 -->
<property name="dataSource" ref="dataSource" />
<!-- 配置mybatis核心配置文件位置 -->
<property name="configLocation" value="classpath:SqlMapConfig.xml" />
</bean>
</beans>
- 編寫UserMapper.xml配置文件
<?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="cn.itcast.mybatis.mapper.UserMapper">
<!-- 根據用戶id查詢 -->
<select id="queryUserById" parameterType="int" resultType="user">
select * from user where id = #{id}
</select>
<!-- 根據用戶名模糊查詢用戶 -->
<select id="queryUserByUsername" parameterType="string"
resultType="user">
select * from user where username like '%${value}%'
</select>
<!-- 添加用戶 -->
<insert id="saveUser" parameterType="user">
<selectKey keyProperty="id" keyColumn="id" order="AFTER"
resultType="int">
select last_insert_id()
</selectKey>
insert into user
(username,birthday,sex,address) values
(#{username},#{birthday},#{sex},#{address})
</insert>
</mapper>
- 編寫UserMapper接口,與UserMapper.xml文件放在同一個目錄下
public interface UserMapper {
/**
* 根據用戶id查詢
*
* @param id
* @return
*/
User queryUserById(int id);
/**
* 根據用戶名模糊查詢用戶
*
* @param username
* @return
*/
List<User> queryUserByUsername(String username);
/**
* 添加用戶
*
* @param user
*/
void saveUser(User user);
}
在spring配置文件中配置mapper代理
自動手動獲得代理對象需要通過sqlSession來獲得代理對象
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
交給spring容器管理後,就需要先給一個sqlSession對象,獲得sqlSession對象,需要注入sqlSessionFactory。獲得代理對象需要給一個Mapper對象的接口,所以將接口注入到MapperFactoryBean中
<!-- Mapper代理的方式開發方式一,配置Mapper代理對象,生成mapper實現類的工廠 -->
<bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
<!-- 注入sqlSessionFactory -->
<property name="sqlSessionFactory" ref="sqlSessionFactory" />
<!-- 配置Mapper接口 -->
<property name="mapperInterface" value="cn.itcast.mybatis.mapper.UserMapper" />
</bean>
- 測試
package cn.itcast.mybatis.junit;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import cn.itcast.mybatis.mapper.UserMapper;
import cn.itcast.mybatis.pojo.User;
public class JunitTest {
@Test
public void testMapper() throws Exception {
ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
//通過接口獲得代理對象
UserMapper mapper = ac.getBean(UserMapper.class);
//通過id獲得代理對象
//UserMapper mapper = (UserMapper) ac.getBean("userMapper");
User user = mapper.queryUserById(10);
System.out.println(user);
}
}
掃描開發(推薦)
- 修改applicationContext.xml配置文件
這裏不需要注入sqlSessionFactory對象,因爲一旦配置加載了sqlSessionFactory對象,就在spring的容器中,MapperScannerConfigurer會自動掃描獲取 ,所以只需要指定基本包,就會自動掃描mapper配置文件。
<!-- Mapper動態代理開發—掃描-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!-- 基本包 -->
<property name="basePackage" value="com.itheima.mybatis.mapper"/>
</bean>
- 測試
package cn.itcast.mybatis.junit;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import cn.itcast.mybatis.mapper.UserMapper;
import cn.itcast.mybatis.pojo.User;
public class JunitTest {
@Test
public void testMapper() throws Exception {
ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml");
//通過接口獲得代理對象
UserMapper mapper = ac.getBean(UserMapper.class);
//通過id獲得代理對象,由於通過自動掃描的方式獲得,沒有命名id,所以就不能通過這種方式獲得mapper代理對象。
//UserMapper mapper = (UserMapper) ac.getBean("userMapper");
User user = mapper.queryUserById(10);
System.out.println(user);
}
}