Explication détaillée de la redirection Java de l'arrière-plan vers un autre projet

@RequestMapping("alipayforward") 
  public ModelAndView alipayforward(HttpServletRequest req, HttpServletResponse resp) throws Exception { 
    String contNo =req.getParameter("contNo"); 
    logger.info("访问/downloadRequestElecCont.action"); 
    String url = "redirect:http://baidu.com/downloadRequestElecCont.action?contNo="+contNo;  
    return new ModelAndView(url); 
  }

@RequestMapping("alipayforward/{contNo}") 
  public void alipayforward(@PathVariable("contNo") String contNo, HttpServletRequest req, HttpServletResponse resp) throws Exception { 
    //String contNo =req.getParameter("contNo"); //保单号 
    logger.info("访问/downloadRequestElecCont.action"); 
    resp.sendRedirect("http://baidu.com/downloadRequestElecCont.action?contNo="+contNo); 
  }

@RequestMapping("alipayforward") 
  public String alipayforward(@RequestParam("contNo") String contNo, HttpServletRequest req, HttpServletResponse resp) throws Exception { 
    //String contNo =req.getParameter("contNo"); //保单号 
    logger.info("访问/downloadRequestElecCont.action"); 
    return "redirect:http://baidu.com/downloadRequestElecCont.action?contNo="+contNo; 
  }

@RequestMapping(params = "action=alipayforward") 
  public String alipayforward(Map modelMap){ 
    modelMap.put("userName", "呵呵"); 
    modelMap.put("password", "123456"); 
    modelMap.put("age", "25"); 
    return "redirect:http://localhost:8088/era/user/alipayforward4?modelMap="+modelMap; 
  }

@RequestMapping("alipayforward4") 
  public void alipayforward4(User user, HttpServletRequest req) throws Exception { 
    System.out.println(user.getPassword()); 
    String modelMap = req.getParameter("modelMap"); 
    System.out.println(modelMap); 
  }