SpringMVC入门学习体验（1）基于xml的MultiActionController
学习Spring框架有一两个礼拜了，在这之前JAVA SSH的基础几乎没有，一直从事WPF的那一套开发，之前做的网页比较小用javaBean+servlet+jsp自己都能解决，但是跨到javaWeb学习之后还是有点教训和经验，我还没到大牛的层次，在应用层面上来说，C#和JavaWeb的开发的差别还是有点大的。废话说少点，最好在学Spring之前有struts的一些常识，不然以些bean的概念理解起来有些头疼。言归正转：
SpringMVC基本上有三种模式：基于XML，基于注解，基于java类；第一种，简单的来说就是利用反射来装载配置文件，第二种，就是注解后自动加载，大大节省人力，第三种，类似第二种，更加灵活，我还不是很熟悉；不过一般开发，都是基于注解的模式。
在这里我有些话说，有编程基础的，可能直接照着例子ctrl+c和ctrl+v注解模式感觉很简单，也很容易，只要完成就行了，如果你的任务是这个，那恭喜你，你成功了！我学习的经验是，因为是按照先后顺序发展的，如果你直接学注解，可能你就是知其然不知其所以然了，所以，还是得从基础的xml配置学起，一步一步的成为大牛.
首先还是配置Spring的web.xml文件交代清楚如何启动等……
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1"> <servlet> <servlet-name>dispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/dispatcherServlet-servlet.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>dispatcherServlet</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> </web-app>再接着就是配置web.xml中提到的dispatcherServlet-servlet.xml
<?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:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd"> <!-- 定义映射 --> <bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <property name="mappings"> <props> <prop key="helloWorld.do">helloWorldAction</prop> </props> </property> </bean> <!-- 定义视图及jsp存放路径 --> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass"> <value>org.springframework.web.servlet.view.InternalResourceView</value> </property> <property name="prefix"> <value>/WEB-INF/pages/</value> </property> <property name="suffix"> <value>.jsp</value> </property> </bean> <!-- 定义控制器 --> <bean id="helloWorldAction" class="com.gc.action.HelloWorldAction"> <property name="methodNameResolver"> <ref bean="paraMethodResolver"/> </property> <property name="viewPage"> <value>show</value> </property> </bean> <!-- 定义动作参数 --> <bean id="paraMethodResolver" class="org.springframework.web.servlet.mvc.multiaction.ParameterMethodNameResolver"> <property name="paramName"> <value>method</value> </property> </bean> </beans>
最后就是来是来实现我们定义的控制器了。
package com.gc.action;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.bind.ServletRequestBindingException;
import org.springframework.web.bind.ServletRequestUtils;
import org.apache.log4j.Logger;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;
public class HelloWorldAction extends MultiActionController {
private Logger logger = Logger.getLogger(this.getClass().getName());
private String viewPage;
public ModelAndView insert(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "insert:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public ModelAndView delete(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "delete:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public ModelAndView update(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "update:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public String getViewPage() {
return viewPage;
}
public void setViewPage(String viewPage) {
this.viewPage = viewPage;
}
}
当然，我们可能还要有用来展示的入口网页在webContent目录下（不要放到webContent/WEB-INF下，tomcat对这个目录保护，在浏览器中是不能直接访问的）input.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="helloWorld.do" method="post">
Welcome<input type="text" name="msg" value=""/>
<input type="submit" name="method" value="insert" />
<input type="submit" name="method" value="update" />
<input type="submit" name="method" value="delete" />
</form>
</body>
</html>
最后用来显示最终结果的的页面，放在WEB-INF目录下：show.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>
<% String str = (String)request.getAttribute("helloWorld"); %>
<body>
<form action="/8_4/helloWorld.do" name="HelloWorld" method="post">
you Enter is :${helloWorld }<br>
</form>
</body>
</body>
</html>
最后的结果截图：
入口：
结果页显示：
还有一种方案，即不继承MultiActionController,在配置文件中完成。
HelloWorldAction.java修改如下：
package com.gc.action;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.bind.ServletRequestBindingException;
import org.springframework.web.bind.ServletRequestUtils;
import org.apache.log4j.Logger;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;
//public class HelloWorldAction extends MultiActionController {
public class HelloWorldAction {
private Logger logger = Logger.getLogger(this.getClass().getName());
private String viewPage;
public ModelAndView insert(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "insert:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public ModelAndView delete(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "delete:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public ModelAndView update(HttpServletRequest req, HttpServletResponse res)
throws ServletRequestBindingException {
String helloWorld = ServletRequestUtils.getRequiredStringParameter(req,
"msg");
Map model = new HashMap();
model.put("helloWorld", "update:" + helloWorld);
return new ModelAndView(getViewPage(), model);
}
public String getViewPage() {
return viewPage;
}
public void setViewPage(String viewPage) {
this.viewPage = viewPage;
}
}
在修改bean配置文件dispatcherServlet-servlet.xml：使用代理来实现
<?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:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd"> <!-- 定义映射 --> <bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping"> <property name="mappings"> <props> <prop key="helloWorld.do">action</prop> </props> </property> </bean> <!-- 定义视图及jsp存放路径 --> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass"> <value>org.springframework.web.servlet.view.InternalResourceView</value> </property> <property name="prefix"> <value>/WEB-INF/pages/</value> </property> <property name="suffix"> <value>.jsp</value> </property> </bean> <!-- 定义控制器 --> <bean id="helloWorldAction" class="com.gc.action.HelloWorldAction"> <!-- <property name="methodNameResolver"> <ref bean="paraMethodResolver"/> </property> --> <property name="viewPage"> <value>show</value> </property> </bean> <!-- 定义动作参数 --> <bean id="paraMethodResolver" class="org.springframework.web.servlet.mvc.multiaction.ParameterMethodNameResolver"> <property name="paramName"> <value>method</value> </property> </bean> <!-- 使用多控制器代理类 --> <bean id="action" class="org.springframework.web.servlet.mvc.multiaction.MultiActionController"> <property name="methodNameResolver"> <ref bean="paraMethodResolver"/> </property> <property name="delegate"> <ref bean="helloWorldAction"/> </property> </bean> </beans>