jsp的Integer.parseInt(request.getParameter())语句报错

Question

问题遇到的现象和发生背景

jsp的Integer.parseInt(request.getParameter())语句报错
显示java.lang.NumberForamtException:Null

问题相关代码，请勿粘贴截图

<%
    String id = "";
    String name = "";
    String sex = "";
    int age = 0;
    String college = "";
    
    String strURL,strSQL;
    Connection conn;  
    Statement stmt;     
    
    request.setCharacterEncoding("utf-8"); 
    
    id = request.getParameter("hidnStuID");
    name = request.getParameter("name");
    sex = request.getParameter("sex");
    age = Integer.parseInt(request.getParameter("age"));    //--------报错语句--------
    college = request.getParameter("college");
        
    try{
        Class.forName("com.mysql.jdbc.Driver").newInstance();    
    strURL="jdbc:mysql://localhost:3306/student?serverTimezone=GMT%2B8";    
    conn=DriverManager.getConnection(strURL,"root","123456");      
    stmt=conn.createStatement();
                
        strSQL="update sy6 set name = '" + name + "',sex = '" + sex + "',age = " + age + ",college = '" + college + "' where id = '" + id + "'";
        stmt.executeUpdate(strSQL);
        out.println("学生信息修改已经完成！！");    
        
        stmt.close();
        conn.close();
    }
      catch(Exception e){
        out.println(e);
    }
    

运行结果及报错内容

希望大家帮帮我！

Answer 1

request.getParameter("age") 返回的是null 检查一下数据是否缺失