Mybatis整合spring
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。
配置文件
1.mybatisSpring的配置文件
2.mybatis配置文件sqlmapConfig.xml
sqlmpConfig.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="cn.itcast.mybatis.pojo" />
</typeAliases>
</configuration>
整合Mybatis需要的是SqlSessionFactoryBean
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.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>
Dao的开发
1、原始dao的开发方式
1POJO
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。。。
}
2编写User.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="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>
3加载mapper.xml
在SqlMapConfig如下图进行配置:
4实现接口
public interface UserDao {
//根据id查询用户
User queryUserById(int id);
List<User> queryUserByUsername(String username);
void saveUser(User user);
}
5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 {
@Override
public User queryUserById(int id) {
// 获取SqlSession
SqlSession sqlSession = super.getSqlSession();
// 使用SqlSession执行操作
User user = sqlSession.selectOne("queryUserById", id);
// 不要关闭sqlSession
return user;
}
@Override
public List<User> queryUserByUsername(String username) {
// 获取SqlSession
SqlSession sqlSession = super.getSqlSession();
// 使用SqlSession执行操作
List<User> list = sqlSession.selectList("queryUserByUsername", username);
// 不要关闭sqlSession
return list;
}
@Override
public void saveUser(User user) {
// 获取SqlSession
SqlSession 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
}
}
6.配置dao
测试方法:
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userDao
UserDao userDao = this.context.getBean(UserDao.class);
User user = userDao.queryUserById(1);
System.out.println(user);
}
@Test
public void testQueryUserByUsername() {
// 获取userDao
UserDao 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userDao
UserDao 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);
}
}
2、使用Mapper代理形式开发方式
1配置UserMapper.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="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>
2实现接口
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);
}
3配置mapper代理
a)直接配置Mapper代理
<!-- 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>
b)使用扫描包配置Mapper代理
<!-- 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>
实现:
public class UserMapperTest {
private ApplicationContext context;
@Before
public void setUp() throws Exception {
this.context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
}
@Test
public void testQueryUserById() {
// 获取Mapper
UserMapper userMapper = this.context.getBean(UserMapper.class);
User user = userMapper.queryUserById(1);
System.out.println(user);
}
@Test
public void testQueryUserByUsername() {
// 获取Mapper
UserMapper userMapper = this.context.getBean(UserMapper.class);
List<User> list = userMapper.queryUserByUsername("张");
for (User user : list) {
System.out.println(user);
}