MyBatis（9）整合spring
具体的感兴趣可以参考：MyBatis
此时此刻，没用的话不再多说了，直接开始代码工程吧！
整体的代码实现：
具体使用到的我们在进行细说
基本上理解一边就能会使用整合
准备工作：
db.properties
jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3307/shopping jdbc.username=root jdbc.password=12345
log4j.properties
#Global logging configuration # 在开发环境下日志级别要设成 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
applivationContext.xml
mvc,context,aop,tx,beans...命名约束
<!-- 加载配置文件 -->
<context:property-placeholder location="classpath:db.properties" />
使用dbcp数据库连接池
<!-- 数据源，使用dbcp -->
<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
不需要在类中单独进行配置
<!-- sqlSessinFactory -->
<!-- org.mybatis.spring.SqlSessionFactoryBean -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 加载mybatis的配置文件 -->
<property name="configLocation" value="mybatis/SqlMapConfig.xml" />
<!-- 数据源 -->
<property name="dataSource" ref="dataSource" />
</bean>
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> <typeAliases> <package name="com.MrChengs.po"/> </typeAliases> <!-- 加载 映射文件 --> <mappers> <mapper resource="sqlmap/User.xml"/> </mappers> </configuration>
其他的设置项在使用的时候在进行添加,,,,,,
一.dao开发
Userser.xml
简单的小案例进行测试，其余的代码和之前的方法一样
<?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"> <select id="findUserByID" parameterType="int" resultType="com.MrChengs.po.User"> select * from user where id=#{id} </select> </mapper>
UserDao.java
public interface UserDao { //根据id查询用户信息 public User findUserById(int id) throws Exception; }
UserDaoImp.java
让实现接口类的类继承SqlSessionDaoSupport
通过spring进行注入，声明配置方式，配置dao的bean
此时不需要手动配置SqlSessionFactory
直接可以得到其对象
此时不需要手动关闭，在spring容器池里会自动关闭
public class UserDaoImp extends SqlSessionDaoSupport implements UserDao { @Override public User findUserById(int id) throws Exception { SqlSession sqlSession = this.getSqlSession(); User user =sqlSession.selectOne("test.findUserByID", id); return user; } }
applivationContext.xml
注入sqlSessionFactory
<bean id="userDao" class="com.MrChengs.UserDao.UserDaoImp">
<property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>
测试：
public class Test { private ApplicationContext applicationContext; public ApplicationContext getApplication(){ applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext.xml"); return applicationContext; } //Dao开发 @org.junit.Test public void testDao() throws Exception{ UserDao userdao = (UserDao) getApplication().getBean("userDao"); User user = userdao.findUserById(1); System.out.println(user); } }
DEBUG [main] - ==> Preparing: select * from user where id=? DEBUG [main] - ==> Parameters: 1(Integer) DEBUG [main] - <== Total: 1 DEBUG [main] - Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@3bf7ca37] DEBUG [main] - Returning JDBC Connection to DataSource User [id=1, username=王五, birthday=null, sex=2, address=null]
二.Mapper代理开发
UserMapper.java
//相当于dao接口 public interface UserMapper { //根据id查询用户信息 public User findUserById(int id) throws Exception; }
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="com.MrChengs.mapper.UserMapper"> <select id="findUserById" parameterType="int" resultType="com.MrChengs.po.User"> SELECT * FROM USER WHERE id=#{value} </select> </mapper>
注意上述的两个文件在一个路径下。
SqlMapConfig.xml
<!-- 加载 映射文件 -->
<mappers>
<mapper resource="sqlmap/User.xml"/>
<package name="com.MrChengs.mapper"/>
</mappers>
通过MapperFactoryBean创建代理对象
<!-- mapper配置 MapperFactoryBean：根据mapper接口生成代理对象 --> <!-- mapperInterface指定mapper接口 --> <bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean"> <property name="mapperInterface" value="com.MrChengs.mapper.UserMapper"/> <property name="sqlSessionFactory" ref="sqlSessionFactory"/> </bean>
测试：
public class TestMapper { private ApplicationContext applicationContext; public ApplicationContext getApplication(){ applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext.xml"); return applicationContext; } //Mapper开发 @org.junit.Test public void testmapper() throws Exception{ UserMapper user = (UserMapper) getApplication().getBean("userMapper"); User u = user.findUserById(1); System.out.println(u); } }
DEBUG [main] - ==> Preparing: SELECT * FROM USER WHERE id=? DEBUG [main] - ==> Parameters: 1(Integer) DEBUG [main] - <== Total: 1 DEBUG [main] - Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7c729a55] DEBUG [main] - Returning JDBC Connection to DataSource User [id=1, username=王五, birthday=null, sex=2, address=null]
如果有很多个类都需要对每个mapper进行配置，此时需要大量的工程???
<bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean"> <property name="mapperInterface" value="com.MrChengs.mapper.UserMapper"/> <property name="sqlSessionFactory" ref="sqlSessionFactory"/> </bean> 。。。。。
通过MapperScannerConfigurer进行mapper扫描（建议使用）
applicationContext.xml
说明：
mapper批量扫描，从mapper包中扫描出mapper接口，自动创建代理对象并且在spring容器中注册
遵循规范：将mapper.java和mapper.xml映射文件名称保持一致，且在一个目录 中
自动扫描出来的mapper的bean的id为mapper类名（首字母小写）
name="basePackage"
指定扫描的包名
如果扫描多个包，每个包中间使用半角逗号分隔
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.MrChengs.mapper"/>
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
</bean>
其余的测试不变......
