整合思路
1、SqlSessionFactory对象应该放到spring容器中作为单例存在。
2、传统dao的开发方式中,应该从spring容器中获得sqlsession对象。
3、Mapper代理形式中,应该从spring容器中直接获得mapper的代理对象。
4、数据库的连接以及数据库连接池事务管理都交给spring容器来完成。
整合需要的jar包
1、spring的jar包
2、Mybatis的jar包
3、Spring+mybatis的整合包。
4、Mysql的数据库驱动jar包。
5、数据库连接池的jar包。
配置文件
SqlMapConfig.xml
配置文件是SqlMapConfig.xml,如下:
<?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><!-- 设置别名 --><typeAliases><!-- 2. 指定扫描包,会把包内所有的类都设置别名,别名的名称就是类名,大小写不敏感 --><package name="cn.itcast.mybatis.pojo" /></typeAliases></configuration>
applicationContext.xml
SqlSessionFactoryBean属于mybatis-spring这个jar包
如何查看SqlSessionFactoryBean源码?
对于spring来说,mybatis是另外一个架构,需要整合jar包。
在项目中加入mybatis-spring-1.2.2.jar的源码,如下图
效果,如下图所示,图标变化,表示源码加载成功:
整合Mybatis需要的是SqlSessionFactoryBean,位置如下图:
applicationContext.xml,配置内容如下
<?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.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsdhttp://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.xsdhttp://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"><!-- 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mybatis核心配置文件 --><property name="configLocation" value="classpath:SqlMapConfig.xml" /><!-- 配置数据源 --><property name="dataSource" ref="dataSource" /></bean>
</beans>
db.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8
jdbc.username=root
jdbc.password=root
log4j.properties
# 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
效果
Dao的开发
两种dao的实现方式:
1、原始dao的开发方式
2、使用Mapper代理形式开发方式
a) 直接配置Mapper代理
b) 使用扫描包配置Mapper代理
需求:
1. 实现根据用户id查询
2. 实现根据用户名模糊查询
3. 添加用户
创建pojo
public class User {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get/set。。。
}
传统dao的开发方式
原始的DAO开发接口+实现类来完成。
需要dao实现类需要继承SqlsessionDaoSupport类
实现Mapper.xml
编写User.xml配置文件,如下:
<?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="test"><!-- 根据用户id查询 --><select id="queryUserById" parameterType="int" resultType="user">select * from user where id = #{id}</select><!-- 根据用户名模糊查询用户 --><select id="queryUserByUsername" parameterType="string"resultType="user">select * from user where username like '%${value}%'</select><!-- 添加用户 --><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>
加载Mapper.xml
在SqlMapConfig如下图进行配置:
实现UserDao接口
public interface UserDao {/*** 根据id查询用户* * @param id* @return*/User queryUserById(int id);/*** 根据用户名模糊查询用户列表* * @param username* @return*/List<User> queryUserByUsername(String username);/*** 保存* * @param user*/void saveUser(User user);}
实现UserDaoImpl实现类
编写DAO实现类,实现类必须集成SqlSessionDaoSupport
SqlSessionDaoSupport提供getSqlSession()方法来获取SqlSession
public class UserDaoImpl extends SqlSessionDaoSupport implements UserDao {@Overridepublic User queryUserById(int id) {// 获取SqlSessionSqlSession sqlSession = super.getSqlSession();// 使用SqlSession执行操作User user = sqlSession.selectOne("queryUserById", id);// 不要关闭sqlSessionreturn user;}@Overridepublic List<User> queryUserByUsername(String username) {// 获取SqlSessionSqlSession sqlSession = super.getSqlSession();// 使用SqlSession执行操作List<User> list = sqlSession.selectList("queryUserByUsername", username);// 不要关闭sqlSessionreturn list;}@Overridepublic void saveUser(User user) {// 获取SqlSessionSqlSession sqlSession = super.getSqlSession();// 使用SqlSession执行操作sqlSession.insert("saveUser", user);// 不用提交,事务由spring进行管理// 不要关闭sqlSession}
}
配置dao
把dao实现类配置到spring容器中,如下图
测试方法
创建测试方法,可以直接创建测试Junit用例。
如下图所示进行创建。
编写测试方法如下:
public class UserDaoTest {
private ApplicationContext context;
@Before
public void setUp() throws Exception {this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
}@Test
public void testQueryUserById() {// 获取userDaoUserDao userDao = this.context.getBean(UserDao.class);User user = userDao.queryUserById(1);System.out.println(user);
}@Test
public void testQueryUserByUsername() {// 获取userDaoUserDao userDao = this.context.getBean(UserDao.class);List<User> list = userDao.queryUserByUsername("张");for (User user : list) {System.out.println(user);}
}@Test
public void testSaveUser() {// 获取userDaoUserDao userDao = this.context.getBean(UserDao.class);User user = new User();user.setUsername("曹操");user.setSex("1");user.setBirthday(new Date());user.setAddress("三国");userDao.saveUser(user);System.out.println(user);
}
}
Mapper代理形式开发dao
编写UserMapper.xml配置文件,如下:
<?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"><!-- 根据用户id查询 --><select id="queryUserById" parameterType="int" resultType="user">select * from user where id = #{id}</select><!-- 根据用户名模糊查询用户 --><select id="queryUserByUsername" parameterType="string"resultType="user">select * from user where username like '%${value}%'</select><!-- 添加用户 --><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>
实现UserMapper接口
public interface UserMapper {/*** 根据用户id查询* * @param id* @return*/User queryUserById(int id);/*** 根据用户名模糊查询用户* * @param username* @return*/List<User> queryUserByUsername(String username);/*** 添加用户* * @param user*/void saveUser(User user);
}
方式一:配置mapper代理
在applicationContext.xml添加配置
MapperFactoryBean也是属于mybatis-spring整合包
<!-- Mapper代理的方式开发方式一,配置Mapper代理对象 -->
<bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean"><!-- 配置Mapper接口 --><property name="mapperInterface" value="cn.itcast.mybatis.mapper.UserMapper" /><!-- 配置sqlSessionFactory --><property name="sqlSessionFactory" ref="sqlSessionFactory" />
</bean>
测试方法
public class UserMapperTest {private ApplicationContext context;@Beforepublic void setUp() throws Exception {this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");}@Testpublic void testQueryUserById() {// 获取MapperUserMapper userMapper = this.context.getBean(UserMapper.class);User user = userMapper.queryUserById(1);System.out.println(user);}@Testpublic void testQueryUserByUsername() {// 获取MapperUserMapper userMapper = this.context.getBean(UserMapper.class);List<User> list = userMapper.queryUserByUsername("张");for (User user : list) {System.out.println(user);}}@Testpublic void testSaveUser() {// 获取MapperUserMapper userMapper = this.context.getBean(UserMapper.class);User user = new User();user.setUsername("曹操");user.setSex("1");user.setBirthday(new Date());user.setAddress("三国");userMapper.saveUser(user);System.out.println(user);}
}
方式二:扫描包形式配置mapper
<!-- Mapper代理的方式开发方式二,扫描包方式配置代理 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><!-- 配置Mapper接口 --><property name="basePackage" value="cn.itcast.mybatis.mapper" />
</bean>
每个mapper代理对象的id就是类名,首字母小写
练习代码保存
applicationContext.xml
<?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.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsdhttp://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.xsdhttp://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"><!-- 加载配置文件 --><context:property-placeholder location="classpath:db.properties" /><context:component-scan base-package="com.itcast.dao"></context:component-scan><!-- 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 name="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"><!-- 配置mybatis核心配置文件 --><property name="configLocation" value="classpath:SqlMapConfig.xml" /><!-- 依赖注入 -配置数据源 --><property name="dataSource" ref="dataSource" /></bean><!-- 原始DAO开发 配置UserDaoImpl --><bean name="userDao" class="com.itcast.dao.UserDaoImpl"><!-- 配置sqlSessionFactory --><property name="sqlSessionFactory" ref="sqlSessionFactory"></property></bean><!-- mybatis中mapper动态代理 --><!-- <bean name="mapperFactoryBean" class="org.mybatis.spring.mapper.MapperFactoryBean"><property name="sqlSessionFactory" ref="sqlSessionFactory"></property><property name="mapperInterface" value="com.itcast.mapper.mapper" /></bean> --><!-- 增强版mapper动态代理 --><bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><!-- 此时不需要写得到sqlSessionFactory,因为sqlsessionfactory配置在spring容器当中它自动会去找 --><property name="basePackage" value="com.itcast.mapper"></property></bean>
</beans>
mapper动态代理代码
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><!-- 设置别名 --><typeAliases><!-- 2. 指定扫描包,会把包内所有的类都设置别名,别名的名称就是类名,大小写不敏感 --><package name="com.itcast.dao" /></typeAliases><mappers><mapper resource="UserMapper.xml"/><!-- 当DAO用传统的DAO开发的时候不能用其他的方式导入mapper.xml文件只能用package --><package name="com.itcast.mapper"/></mappers>
</configuration>
mapper.xml
<?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.itcast.mapper.mapper"><!-- 通过ID查询一个用户 --><select id="queryUserById" parameterType="Integer" resultType="com.itcast.pojo.User"><!-- <include refid="selector"></include> -->select * from user where id = #{id}</select>
</mapper>
mapper.java
package com.itcast.mapper1;import com.itcast.pojo1.User;public interface mapper {public User queryUserById(Integer id);
}
原始DAO开发方式代码
UserDao.java
package com.itcast.dao;import com.itcast.pojo1.User;public interface UserDao {public User queryUserById(Integer id);public Integer countUser();
}
UserDaoImpl.java
package com.itcast.dao;import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.support.SqlSessionDaoSupport;import com.itcast.pojo1.User;public class UserDaoImpl extends SqlSessionDaoSupport implements UserDao {@Overridepublic User queryUserById(Integer id) {SqlSession session = super.getSqlSession();User user = session.selectOne("queryUserById", id);return user;}@Overridepublic Integer countUser() {SqlSession session = super.getSqlSession();Integer s = session.selectOne("countUser");return s;}
}
测试类
package com.itcast.test;import javax.annotation.Resource;import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;import com.itcast.dao.UserDao;
import com.itcast.mapper1.mapper;
import com.itcast.pojo1.User;
/*@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")*/
public class TestUserDaoDemo1 {@Resource(name="userDao")public UserDao userDao;private ApplicationContext context;/*传统DAO开发方式*/@Testpublic void testDemo() {this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");UserDao userDao = (UserDao) context.getBean("userDao");User user = userDao.queryUserById(1);System.out.println(user);}/*mapper动态代理,不需要写实现类只需要写接口即可*/@Testpublic void testDemo1() {this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");UserDao userDao = (UserDao) context.getBean("userDao");Integer s = userDao.countUser();System.out.println(s);}/*mapper动态代理增强版,解决了上述方式中多个mapper文件都需要手动导入*/@Testpublic void testDemo2() {this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");/*有两种方式可以加载mapper 通过文件名字或者是mapper.class*/mapper bean = (mapper) context.getBean("mapper");User user = bean.queryUserById(1);System.out.println(user);}
}