springmvc的一个小例子(一)
个人觉得,学框架最好的 方法无外乎两个:一个是实践这个框架,真实的去用它,比如spring框架,先搭一个简单的spring项目,然后一步一步得去丰富它,从中学到spring框架的精髓和知识;另外一个就是看源码了,这个被无数大神推荐过,不过他需要一定的能力(至少你要有一定的设计模式的知识积累和足够牛的java coding能力)。
今天就简单实现一下springmvc:
首先,创建一个maven-archetype-webapp项目,路径图如下:

pom文件,导入需要的jar包:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.xuejupo</groupId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>test Maven Webapp</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<spring.version>3.2.4.RELEASE</spring.version>
</properties>
<dependencies>
<!-- junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12-beta-3</version>
<scope>test</scope>
</dependency>
<!-- log4j -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!-- spring 的基本依赖 开始 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
<!-- spring 的基本依赖 结束 -->
</dependencies>
<build>
<finalName>test</finalName>
</build>
<artifactId>test</artifactId>
</project>然后是web.xml文件:
<?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">
<!-- 区分项目名称,防止默认重名 -->
<context-param>
<param-name>webAppRootKey</param-name>
<param-value>maven.cainiao.root</param-value>
</context-param>
<!-- Spring的log4j监听器 -->
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<!-- 字符集 过滤器 -->
<filter>
<filter-name>CharacterEncodingFilter</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>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- Spring view分发器 -->
<servlet>
<servlet-name>dispatcher_cainiao</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/dispatcher_cainiao.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcher_cainiao</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>dispatcher_cainiao.xml:(这就是mvc中的c,控制层)
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<mvc:annotation-driven />
<!-- <mvc:default-servlet-handler/> -->
<context:component-scan base-package="controller" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/views/" />
<property name="suffix" value=".jsp" />
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
</bean>
</beans>user类:(mvc中的m,模型层)
package com.beans; /** * User : 用户bean * @author xuejupo [email protected] * * create in 2016-3-1 下午4:23:16 */ public class User { public final String getUserId() { return userId; } public final void setUserId(String userId) { this.userId = userId; } public final String getUserName() { return userName; } public final void setUserName(String userName) { this.userName = userName; } public final String getPasswd() { return passwd; } public final void setPasswd(String passwd) { this.passwd = passwd; } public final String getInfo() { return info; } public final void setInfo(String info) { this.info = info; } private String userId; private String userName; private String passwd; private String info; @Override public String toString(){ return "用户名:\r\n"+this.userName + "用户密码:\r\n"+this.passwd + "用户的信息:\r\n"+ this.info; } }
控制器DispatcherController(和dispatcher_cainiao.xml文件一起组成控制层,控制着传入的url应该使用哪部分代码逻辑和使用哪个model层):
package controller; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.ui.ModelMap; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import com.test.beans.User; /** * DispatcherController: * @author xuejupo [email protected] * * create in 2016-3-1 下午3:35:13 * */ @Controller @RequestMapping("demo") public class DispatcherController { @RequestMapping(method=RequestMethod.GET) public String printWelcome(ModelMap model) { User user = new User(); user.setInfo("哈哈,我是唯一的用户!"); user.setUserName("我是老大!"); user.setPasswd("不告诉你!"); model.addAttribute("str0121", "我去,成功了呀!!!"); model.addAttribute("info","当前用户信息为:"); model.addAttribute("user", user); System.out.println("index.jsp"); return "index"; } }
index.jsp(mvc中的v层,展示层,负责向前端展示结果,直接和用户打交道的层)
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!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>
<c:out value="${str0121}"></c:out>
<p>
<c:out value="${info}"></c:out>
<p>
<c:out value="${user}"></c:out>
</body>
</html>然后url中输入:http://localhost:8080/test/demo
结果: 
PS:搭建过程中出了两个bug。
1. 因为我用的是jboss,在发布的时候出了这个错:
java.lang.IllegalStateException: Could not detect JBoss VFS infrastructure
网上查询是spring4去掉了对jboss的VFS支持。。。。 所以我的pom里面用的都是spring3.
2.No mapping found for HTTP request with URI
在pom里加入这个依赖:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
就解决了。。 原因暂时不明,网上查询spring-tx提供事务管理功能,提供对JAO和DAO功能的支持。但是具体为啥还未知,欢迎大神留言告知。。。
今天暂只更新这些,下次再具体分析各个配置文件的作用和访问的具体流程。
PS:欢迎转载,转载请标明出处: