spring mvc demo带简单的注册和登录（完整注释）

package org.lee.springmvc.demo; import java.util.HashMap; import org.springframework.validation.BindException; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.mvc.SimpleFormController; public class RegAction extends SimpleFormController{ private String error_view ; private String success_view; private String errorMsg; protected ModelAndView onSubmit(Object cmd,BindException ex) throws Exception { RegInfo regInfo =(RegInfo)cmd ; System.out.println(regInfo.getUserName()); if(isEntity(regInfo)) { HashMap hm = new HashMap(); hm.put("regInfo", regInfo); return new ModelAndView(this.getSuccess_view(),hm); }else { errorMsg="用户名或者密码不能为空！"; HashMap<String,Object> map=new HashMap<String,Object>(); map.put("errorMsg", errorMsg); return new ModelAndView(this.getError_view(),map); } } private boolean isEntity(RegInfo regInfo) { if(regInfo.getUserName() != null && !regInfo.getUserName().trim().equals("") && regInfo.getPassword() !=null && !regInfo.getPassword().trim().equals("")) return true ; else return false ; } public String getError_view() { return error_view; } public void setError_view(String error_view) { this.error_view = error_view; } public String getSuccess_view() { return success_view; } public void setSuccess_view(String success_view) { this.success_view = success_view; } public String getErrorMsg() { return errorMsg; } public void setErrorMsg(String errorMsg) { this.errorMsg = errorMsg; } }