在Struts中使用异常

在Struts中使用异常
1 、自定义用户异常
public class MyException extends Exception {
      private String code;

      public MyException() {
            super();
      }

      public MyException(String code) {
            this.code = code;
      }

      public String getCode() {
            return code;
      }

      public void setCode(String code) {
            this.code = code;
      }
}

2、 在相应的业务方法中抛出异常
public boolean isExistMember(String memberCode)throws MyException{
      List list=(List)baseDAO.getByProperty("TMember","memberCode",memberCode);
      if(list.size()>0){
            throw new MyException("Error_001"); 
      }else{
            return false;
      }
}
3 在Action中作出相应的页面跳转
public ActionForward execute(ActionMapping mapping, ActionForm form,HttpServletRequest request, HttpServletResponse response) {
       AddMemberForm addMemberForm = (AddMemberForm) form  
      try{    
            if(!memberManager.isExistMember(addMemberForm.getMemberCode())){  
                  memberManager.addMember(addMemberForm);
            }
      }catch(MyException ee){
           request.setAttribute("code",ee.getCode());
           return mapping.findForward("error"); 
      }catch(Exception e){
           e.printStackTrace();
      }
      return mapping.findForward("success");
 }

*其中"error","success"要先在对应的Action中配置好,内容如下
      name="addMemberForm"
      path="/addMember"
      scope="request">     

4、首先定义好Struts中常用的标签文件,把这些标签统一放到一个jsp文件中方便在其它页面使用标签时可以直接引用
taglibs.jsp内容如下:

5、 再创建一个引用properties文件的jsp文件
i18n.jsp内容如下:
<fmt:setbundle basename="com.demo.resource.member" var="addMember"></fmt:setbundle>
其中member.properties文件内容如下:
####==============Error====================
Error_001=此会员已存在!

####==============Success====================
Succ_001=增加成功!

6 、在jsp页面使用时:
如在error.jsp内容如下:

<html:html lang="true"> 
  <html:base>     
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 
  
  error.jsp
  <fmt:message bundle="${addMember}"></fmt:message>   
  </html:html>

  <html:html lang="true">   
  <fmt:message bundle="${addMember}"></fmt:message>   
  </html:html>