SpringMVC 调用数据库显示数据
设计流程
.do请求----DispactcherServlet----handlerMapping—NewsListController-ViewResolver-news.jsp
web.xml配置DispacherServlet
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml,classpath:applicationContext.xml</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>
spring-mvc.xml配置handlerMapping
<bean id="handlerMapper" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
<property name="mappings">
<props>
<!--请求为hello.do调用id=helloController-->
<prop key="/hello.do">helloController</prop>
<prop key="/news.do">newsListController</prop>
</props>
</property>
</bean>
编写controller组件
public class NewsListController implements Controller{
//获得NewsDao对象，进行setter注入
private FanNewsDao fanNewsDao;
public void setFanNewsDao(FanNewsDao fanNewsDao) {
this.fanNewsDao = fanNewsDao;
}
@Override
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
// 返回数据设置
ModelAndView mav=new ModelAndView();
//设置返回的jsp
mav.setViewName("news");
List<FanNews> list=fanNewsDao.loadAll();
mav.getModel().put("news", list);
return mav;
}
}
FanNewDao接口实现类，通过注解标志创建对象，fanNewsDao就是Controller配置的属性ref引用的id
//组件扫描，默认id将类名首字母小写构建对象
@Repository("fanNewsDao")
public class JdbcTemplateFanNews implements FanNewsDao {
@Autowired
private JdbcTemplate jdbcTemplate;
public List<FanNews> loadAll() {
String sql="select *from fan_news";
List<FanNews> list=jdbcTemplate.query(sql,new BeanPropertyRowMapper<FanNews>(FanNews.class));
for(FanNews news:list) {
System.out.println(news.getFan_name()+news.getFan_item());
}
return list;
}
}
注释TODO，//TODO window–其他 —tasks，双击定位注解
添加请求追加定义
spring-mvc.xml配置controller
//自动调用set方法，注入fanNewsDao对象
将id为fanNewsDao注入，
<!-- 配置newsListController -->
<bean id="newsListController" class="com.tracy.controller.NewsListController">
<property name="fanNewsDao" ref="fanNewsDao"></property>
</bean>
配置文件，在web.xml初始化配置，加载两个xml文件，将两个xml配置到一个容器，spring-mvc.xml/applicationContext.xml
下面是applicationContext.xml配置
<bean id="dbcp" class="org.apache.commons.dbcp.BasicDataSource">
<property name="username" value="root"></property>
<property name="password" value="123456"></property>
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/test"></property>
</bean>
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<constructor-arg index="0" ref="dbcp"></constructor-arg>
</bean>
<!-- 开启组件扫描 @Contorller @Service @Repository @Component@Resource @Autowired-->
<context:component-scan base-package="com.tracy.dao.impl" />
<!-- <context:component-scan base-package="*"></context:component-scan> -->
</beans>
配置viewResolver
<!-- 配置ViewResolver配置spring-mvc.xml通用资源适配解析器前缀 后缀 -->
<bean id="ModelAndView" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
news.jsp页面显示
使用EL表达式 JSTL标签，引入标签库
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<h1>资讯列表</h1>
${news}
<table>
<c:forEach items="${news}" var="n">
<tr>
<td>${n.id} </td>
<td>${n.fan_item} </td>
</tr>
</c:forEach>
</table>
</body>
</html>
