1.servlet

@GetMapping("/params")
public String test5(HttpServletRequest request){
    String username = request.getParameter("username");
    String password = request.getParameter("password");
    System.out.println(username + " " + password);
    return "test6";
}

2 通过控制器形参获取参数

@GetMapping("/params2")
public String test6(String username,String password){
    System.out.println(username + " " + password);
    return "test6";
}