第一次实际应用Spring MVC

本文介绍如何使用SpringMVC框架搭建一个简单的投票系统。包括web.xml和pollmvc-servlet.xml配置、Controller类定义及视图展示等内容。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

要做一个简单的投票的东西,看spring mvc的文章已经很久了,但是没有实际用过,决定试试看,
首先是web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
<display-name>Spring Annotation MVC Sample</display-name>
<!-- Spring 服务层的配置文件 -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml</param-value>
</context-param>

<!-- Spring 容器启动监听器 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<filter>
<filter-name>Set Character Encoding</filter-name>
<filter-class>
org.springframework.web.filter.CharacterEncodingFilter
</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Set Character Encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

<!--
Spring MVC 的Servlet,
它将加载WEB-INF/annomvc-servlet.xml 的
配置文件,以启动Spring MVC模块
-->
<servlet>
<servlet-name>pollmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>

<servlet-mapping>
<servlet-name>pollmvc</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>

在spring的applicationContext.xml中配置数据源等一些信息,这个网上很多了,主要是pollmvc-servlet.xml配置文件里面写mvc的配置,使用annotation配置就简单很多

<?xml version="1.0" encoding="UTF-8"?>
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd">

<!-- 对web包中的所有类进行扫描,以完成Bean创建和自动依赖注入的功能 -->
<context:component-scan base-package="com.fox.poll"/>

<!-- 启动Spring MVC的注解功能,完成请求和注解POJO的映射
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
-->
<!-- 对模型视图名称的解析,即在模型视图名称添加前后缀 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"
p:prefix="/WEB-INF/jsp/" p:suffix=".jsp"/>
</beans>

在代码里面只需要进行如下配置既可:

package com.nbrc.poll.controller;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import com.nbrc.poll.service.PollService;
import com.nbrc.poll.vo.Candidate;
@Controller
@RequestMapping("/managecandidate.do")
public class CandidateManageController {
@Resource
private PollService service;
}

也可以在方法上用annotation进行声明,这样一来配置文件大大减少
如果页面上有form需要绑定到对象可以通过以下的方式

<form:form commandName="candidate">
候选人姓名:<form:input id="name" path="name"/><br/>
候选人英文名:<form:input id="ename" path="ename"/><br/>
单位名称:<form:input id="corp" path="corp"/><br/>
小图片:<form:input id="simage" path="simage"/><br/>
大图片:<form:input id="bimage" path="bimage"/><br/>
点击后的URL:<form:input id="url" path="url"/><br/>
详细信息:<form:textarea path="info" id="info"/><br/>
<input type="submit" value="保存" />
<input type="reset" value="重置" />
</form:form>

commandName制定的是要显示的对象的在Model中绑定的键的名称,如
model.put("candidate", new Candidate());

最后,当form提交的时候,可以通过标注
public String submitForm(@ModelAttribute("candidate") Candidate c){
进行绑定到对象

自己的感觉来说,spring mvc相对来说比struts2更加灵活一点,strut2对request,response这些进行了封装,但是给我的感觉就是有点不方便了,因为要取原生的这些对象需要很大的精力。例如要生成一个图图形验证码,在spring mvc里感觉就比较好一点,是我感觉问题吗?呵呵

package com.nbrc.poll.controller;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
@Controller
@RequestMapping("/captcha.do")
public class CaptchaImageController {
@RequestMapping(method = RequestMethod.GET)
public void draw(HttpServletRequest request, HttpServletResponse response) {
HttpSession session = request.getSession();

try {
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
int width = 60, height = 20;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
OutputStream os = response.getOutputStream();
Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);

g.setFont(new Font("Times New Roman", Font.PLAIN, 18));
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 155; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
String sRand = "";
for (int i = 0; i < 4; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand += rand;
g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
g.drawString(rand, 13 * i + 6, 16);
}
session.setAttribute("rand", sRand);
g.dispose();

ImageIO.write(image, "JPEG", os);
os.flush();
os.close();
os = null;

} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

private Color getRandColor(int fc, int bc) {
Random random = new Random();
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc);
int g = fc + random.nextInt(bc - fc);
int b = fc + random.nextInt(bc - fc);
return new Color(r, g, b);
}
}
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值