JPetStore-5.0程序中不一样的struts

    平常我们使用struts会定义form，写Action,设置struts-config.xml文件，然后页面的数据是以form对象传给Action，然后调用Service层，完成业务，再返回struts-config.xml配置的页面。
    而JPetStore-5.0的struts不同，例如:
页面是这样的

<html:form method="post" action="/shop/editAccount.shtml">

    <html:hidden name="accountBean" property="validation" value="edit"/>
    <html:hidden name="accountBean" property="username"/>

    <h3>User Information</h3>

    <table>
      <tr>
        <td>User ID:</td><td><bean:write name="accountBean" property="username"/></td>
      </tr><tr>
      <td>New password:</td><td><html:password name="accountBean" property="password"/></td>
    </tr><tr>
      <td>Repeat password:</td><td><html:password name="accountBean" property="repeatedPassword"/></td>
    </tr>
    </table>
    <%@ include file="IncludeAccountFields.jsp" %>

    <input type="submit" name="submit" value="Save Account Information"/>

  </html:form>
  

struts-config.xml的配置文件是这样的

<form-beans>
    <form-bean name="accountBean" type="com.ibatis.jpetstore.presentation.AccountBean"/>
 </form-beans>
 <action path="/shop/editAccount" type="org.apache.struts.beanaction.BeanAction"
            name="accountBean" scope="session"
            validate="true" input="/account/EditAccountForm.jsp">
      <forward name="success" path="/shop/index.shtml"/>
</action>

AccountBean是这样的：

public String editAccount() {
    try {
      accountService.updateAccount(account);
      account = accountService.getAccount(account.getUsername());
      myList = catalogService.getProductListByCategory(account.getFavouriteCategoryId());
      return SUCCESS;
    } catch (Exception e) {
      throw new BeanActionException ("There was a problem updating your Account Information. Cause: "+e, e);
    }
  }

jsp把页面form提交给了/shop/editAccount.shtml，其实所有的数据都提到了一个类里org.apache.struts.beanaction.BeanAction，这个类其实就是一个我们平常写的Action，里面是这样的：

public final ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {
    String forward = SUCCESS_FORWARD;
    try {
      if (!(form instanceof BaseBean)) {
        if (form != null) {
          throw new BeanActionException("The form for mapping '" + mapping.getPath() + "' named '" + mapping.getName() + "' was not an instance of BaseBean.  BeanAction requires an BaseBean instance.");
        } else {
          throw new BeanActionException("The form for mapping '" + mapping.getPath() + "' named '" + mapping.getName() + "' was null.  BeanAction requires an BaseBean instance.");
        }
      }
      BaseBean bean = (BaseBean) form;
      ActionContext.initCurrentContext(request, response);
      if (bean != null) {
        // Explicit Method Mapping

        Method method = null;
        String methodName = mapping.getParameter();
        if (methodName != null && !NO_METHOD_CALL.equals(methodName)) {
          try {
            method = bean.getClass().getMethod(methodName, null);
            synchronized (bean) {
              forward = bean.getInterceptor().intercept(new ActionInvoker(bean, method));
            }
          } catch (Exception e) {
            throw new BeanActionException("Error dispatching bean action via method parameter ('" + methodName + "').  Cause: " + e, e);
          }
        }



        // Path Based Method Mapping

        if (method == null && !NO_METHOD_CALL.equals(methodName)) {
          methodName = mapping.getPath();
          if (methodName.length() > 1) {
            int slash = methodName.lastIndexOf("/") + 1;
            methodName = methodName.substring(slash);
            if (methodName.length() > 0) {
              try {
                method = bean.getClass().getMethod(methodName, null);
                synchronized (bean) {
                  forward = bean.getInterceptor().intercept(new ActionInvoker(bean, method));
                }
              } catch (Exception e) {
                throw new BeanActionException("Error dispatching bean action via URL pattern ('" + methodName + "').  Cause: " + e, e);
              }
            }
          }
        }
      }
    } catch (Exception e) {
      forward = "error";
      request.setAttribute("BeanActionException", e);
    }
    return mapping.findForward(forward);
  }

也就是说，在这个类里，程序会取配置文件里的 parameter 属性是否定义，如果定义了，则就用反射调用com.ibatis.jpetstore.presentation.AccountBean里的相应方法；如果没有定义，则就会去配置文件里的path="/shop/editAccount" 属性，取最后一个斜杠后的单词，再用反射调用相应方法；如个parameter 定义了且是parameter="*"则不调用任何一个方法，直接返回，配置的返回页面。

评论

3 楼 xiaoLee 2010-05-15  

学习了！最近也在研究这个项目

2 楼 Kaede 2008-02-14  

哈哈 这种方式 使得程序更鲜明，层次更清晰，也不显得杂乱～！

1 楼 springrose 2008-01-20  

晕,看不懂列