DispatcherServlet与base-path、流程id、流程定义文件

/WEB-INF/flows/regist/regist-flow.xml，

/WEB-INF/flows/是我们上面配置的base-path，

/regist/regist-flow.xml是/流程id/流程定义文件， 流程点以文件命名为”流程id-flow.xml”，

这样我们访问regist请求时，如果DispatcherServlet找不到对应的处理器，就会交给Web Flow，这样Web Flow就会按照流程定义开始流程。

xml 流程定义

view-state，action-state，decision-state，end-state，subflow-state

  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <flow xmlns="http://www.springframework.org/schema/webflow"
  3.     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  4.     xsi:schemaLocation="http://www.springframework.org/schema/webflow
  5.         http://www.springframework.org/schema/webflow/spring-webflow-2.0.xsd">
  7.     <!-- flow作用域的变量，我们这个流程的模型对象 -->
  8.     <var name="user" 
  9.         class="com.yjp.springmvc.blog.beans.model.User"/>
  11.     <!-- 欢迎界面，默认找welcome.jsp -->
  12.     <view-state id="welcome">
  13.         <transition on="register" to="register"/>
  14.     </view-state>
  16.     <!-- 注册界面，默认找register.jsp -->
  17.     <view-state id="register" model="user">
  18.         <transition on="doRegist" to="doRegist"/>
  19.     </view-state>
  21.     <!-- 使用registAction判断是否注册成功，执行跳转 -->
  22.     <decision-state id="doRegist">
  23.         <if test="registAction.regist(user)" 
  24.             then="complete"
  25.             else="register" />
  26.     </decision-state>
  28.     <!-- 完成界面，默认找complete.jsp -->
  29.     <view-state id="complete" model="user">
  30.         <transition on="login" to="end"/>
  31.     </view-state>
  33.     <!-- 结束状态-->
  34.     <end-state id="end" view="externalRedirect:/"/>
  36.     <!-- 全局转移 -->
  37.     <global-transitions>
  38.         <transition on="cancel" to="end" />
  39.     </global-transitions>
  41. </flow>

使用了view-state，decision-state和end-state，通过转移将他们串联起来。

<global-transitions>全局转移，无论哪个状态以cancel终结，都会进入到end-state。如下图：

Spring MVC-web flow - 图1

decision-state decision-state中使用的action类

  1. package com.yjp.springmvc.blog.web.flowaction;
  3. import org.springframework.beans.factory.annotation.Autowired;
  4. import org.springframework.stereotype.Component;
  6. import com.yjp.springmvc.blog.beans.model.User;
  7. import com.yjp.springmvc.blog.beans.service.UserService;
  9. @Component
  10. public class RegistAction {
  12.     private UserService userService;
  14.     @Autowired
  15.     public RegistAction(UserService userService) {
  16.         this.userService = userService;
  17.     }
  19.     public boolean regist(User user) {
  20.         return userService.saveUser(user);
  21.     }
  22. }

模板文件

welcome.jsp

  1. <%@ page language="java" contentType="text/html; charset=UTF-8"
  2.     pageEncoding="UTF-8"%>
  3. <%@ page isELIgnored="false" %>
  4. <%@ taglib prefix="sf" uri="http://www.springframework.org/tags/form" %>
  5. <!DOCTYPE html>
  6. <html>
  7. <head>
  8.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  9.     <title>欢迎</title>
  10. </head>
  11. <body>
  12.     <h1>欢迎您选择简微</h1>
  13.     如果您喜欢我们的简微，请点击下一步，开始您的旅程<br><br>
  14.     <sf:form>
  15.         <input type="hidden" name="_flowExecutionKey"
  16.             value="${flowExecutionKey} }"/>
  17.         <input type="submit" name="_eventId_register"
  18.             value="下一步"/>
  19.         <input type="submit" name="_eventId_cancel"
  20.             value="取消"/>
  21.     </sf:form>
  22. </body>
  23. </html>

Spring的标签库中的form标签:

eventId事件: 以表明点击该按钮触发的事件，这会用在流程中transition的on属性，用来判断下一步的流程走向。其他的没有特殊的。

register.jsp

  1. <%@ page language="java" contentType="text/html; charset=UTF-8"
  2.     pageEncoding="UTF-8"%>
  3. <%@ taglib prefix="sf" uri="http://www.springframework.org/tags/form" %>
  4. <!DOCTYPE html>
  5. <html>
  6. <head>
  7.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  8.     <title>注册</title>
  9. </head>
  10. <body>
  11.     <h1>会员注册</h1>
  12.     <sf:form commandName="user">
  13.         <input type="hidden" name="_flowExecutionKey"
  14.                 value="${flowExecutionKey} }"/>
  15.         <table style="background-color:#cccccc">
  16.             <tr>
  17.                 <td>邮件地址：</td>
  18.                 <td><sf:input type="emil" path="email" size="25" maxlength="100" cssErrorClass="error"/></td>
  19.             </tr>
  20.             <tr>
  21.                 <td>名称（最大16字符）：</td>
  22.                 <td><sf:input type="text" path="username" size="25" maxlength="16" cssErrorClass="error"/></td>
  23.             </tr>
  24.             <tr>
  25.                 <td>密码（6到16字符）：</td>
  26.                 <td><sf:input type="password" path="password" size="25" maxlength="16" cssErrorClass="error"/></td>
  27.             </tr>
  28.             <tr>
  29.                 <td>确认密码：</td>
  30.                 <td><input type="password" name="confirmedPasswd" size="25" maxlength="16"></td>
  31.             </tr>
  32.             <tr>
  33.                 <td align="center"><input type="submit" name="_eventId_doRegist" value="注册"></td>
  34.                 <td align="center"><input type="submit" name="_eventId_cancel" value="取消"></td>
  35.             </tr>
  36.         </table>
  37.     </sf:form>
  38. </body>
  39. </html>

complete.jsp

  1. <%@ page language="java" contentType="text/html; charset=UTF-8"
  2.     pageEncoding="UTF-8"%>
  3. <%@ page isELIgnored="false" %>
  4. <%@ taglib prefix="sf" uri="http://www.springframework.org/tags/form" %>
  5. <!DOCTYPE html>
  6. <html>
  7. <head>
  8.     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  9.     <title>注册完成</title>
  10. </head>
  11. <body>
  12.     <h1>恭喜  ${user.username} 完成注册</h1>
  13.     <a href="${flowExecutionUrl}&_eventId=login">去登陆</a>
  14. </body>
  15. </html>