mybatis回顾:
- 实体类pojo
- 全局配置文件mybatis.xml
- 配置了数据源，mappers，针对事务的log4j日志，pojo类的简写
- 数据访问层mapper中配置了事务方法，包括接口绑定技术
- MybatisUtil解析mybatis配置文件，创建工厂，拿到session对象，使用ThreadLocal技术进行session对象在创建和关闭两个时刻的传递（范围是同一个线程内）
- filter中openSessionView，filter过滤器过滤请求，当浏览器发送一个请求，过滤器调用MybatisUtil拿到Session，放行，响应时又经过过滤器，提交事务，有错误时完成回滚操作
- serviceImpl中通过mybatis拿到session，如果接口绑定，getMapper拿到接口的对象，调用事务方法，拿到数据库的数据
- servlet正常写
mybatis+spring过程
- spring利用IoC简化了mybatis的过程
- 同样是有实体pojo类
- 需要配置web.xml来解析spring配置文件
- spring+mybatis时 去掉了原先的mybatis配置文件，配置spring配置文件applicationContext.xml
- applicationContext中配置了数据源（可以加属性配置文件），工厂，mapper扫描器三个bean，事务 管理器基于aop管理事务方法，代替了filter中的提交、回滚功能
- mapper照旧
- serviceImpl中注入Mapper（配置bean注入要设置get、set方法，注解注入更方便），业务方法调用注入Mapper中的事务方法return
- servlet中init方法中拿到applicaitonContext对象，spring中所有东西都存在这里边，可以applicaitonContext拿到所有spring管理的对象，servlet中就是拿到Impl对象，其他照旧
jar包
web.xml(用于加载applicationContext.xml)
<?xml version="1.0" encoding="UTF-8"?>
<web-app
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">
</web-app>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
</web-app>
applicationContext.xml
- dataSource就是原来连接数据库的部分
- factory是工厂
- 扫描器是扫描mapper包的，mapper类由spring创建（id为接口名小写）
- serviceImpl由spring进行管理，在servlet中利用spring创建Impl对象，这样可以让spring来完成mapper的注入工作
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
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.xsd">
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/login"></property>
<property name="username" value="root"></property>
<property name="password" value="wityy"></property>
</bean>
<bean id="factory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"></property>
<property name="typeAliasesPackage" value="cn.wit.pojo"></property>
</bean>
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="sqlSessionFactory" ref="factory"></property>
<property name="basePackage" value="cn.wit.mapper"></property>
</bean>
<bean id="loginServiceImpl" class="cn.wit.serviceImpl.LoginServiceImpl">
<property name="usersMapper" ref="usersMapper"></property>
</bean>
<!--事务管理器 -->
<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<tx:advice id="txAdvice" transaction-manager="txManager">
<tx:attributes>
<tx:method name="ins*"/>
<tx:method name="del*"/>
<tx:method name="upd*"/>
<tx:method name="*" read-only="true"/>
</tx:attributes>
</tx:advice>
<!--aop -->
<aop:config>
<aop:pointcut expression="execution(* cn.wit.serviceImpl.*.*(..))" id="mypoint"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="mypoint"/>
</aop:config>
</beans>
pojo类
Users{int id,String userName,String passWord}
Mapper接口
public interface UsersMapper {
Users selByUsers(Users users);
}
业务接口
public interface UsersMapper {
@Select("select *from users where username=#{userName} and password=#{passWord}")
Users selByUsers(Users u);
}
业务Impl
public class UsersServiceImpl implements UsersService {
private UsersMapper usersMapper;
public UsersMapper getUsersMapper() {
return usersMapper;
}
public void setUsersMapper(UsersMapper usersMapper) {
this.usersMapper = usersMapper;
}
@Override
public Users login(Users users) {
return usersMapper.selByUsers(users);
}
}
servlet
@WebServlet("/login")
public class LoginServlet extends HttpServlet {
private LoginService ls;
@Override
public void init() throws ServletException {
ApplicationContext ac = WebApplicationContextUtils.getWebApplicationContext(getServletContext());
ls = ac.getBean("loginServiceImpl",LoginServiceImpl.class);
}
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("text/html;charset=utf-8");
Users u=new Users();
u.setPassWord(req.getParameter("password"));
u.setUserName(req.getParameter("username"));
Users user = ls.login(u);
if(user!=null){
resp.sendRedirect("/login-3/main.jsp");
}else{
resp.sendRedirect("/login-3/login.jsp");
}
}
}
视图
login.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="login" method="post">
<input type="text" name="username">
<input type="password" name="password">
<input type="submit" value="登录">
</form>
</body>
</html>
main.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h1>欢迎回来</h1>
</body>
</html>
另外
Impl注解
需要添加注解扫描
<context:component-scan base-package="cn.wit.serviceImpl"></context:component-scan>
- Impl使用service+Resource注解，可以去掉Impl的bean标签配置，添加注解后默认按照byName方式进行注入，如果byName找不到，就按照byType
@Service
public class LoginServiceImpl implements LoginService{
@Resource
private UsersMapper usersMapper;
@Override
public Users login(Users u) {
return usersMapper.selByUsers(u);
}
}