jsp报错是什么原因，求帮助

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遇到这个问题怎么办，


<%@ page import="bean.Student" %>
<%@ page import="java.util.List" %>
<%@ page import="utils.PageBean" %><%--
  Created by IntelliJ IDEA.
  User: 贺雷
  Date: 2023/6/6
  Time: 8:36
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
    <style>
        table tr td{
            text-align: center;
        }
        form input{
            width: 80px;
        }
    </style>
</head>
<body>
<h1 align="center">学生管理系统</h1>
<%
    List<Student> info= (List<Student>) request.getAttribute("info");//Servlet里面的info是所有成绩，是集合
    PageBean pageBean =(PageBean) request.getAttribute("pagebean");
%>
<div align="center">
<form action="pageAllInfo2">
    <label>
        姓名:<input type="text" name="username" value="<%=pageBean.getName()%>">
    </label>
    <label>
        成绩:<input type="text" name="scoreFrom" value="<%=pageBean.getScoreFrom()%>">-<input type="text" name="scoreTo" value="<%=pageBean.getScoreTo()%>">
    </label>
    <label>
        班级:<input type="text" name="cid" value="<%=pageBean.getCid()%>">
<%--        这个value是让跳出去的javabean留下来--%>
    </label>
    <button type="submit">查询</button>
</form>

<table border="1" cellspacing="0">
    <tr>
       <td>编号</td>
       <td>姓名</td>
       <td>密码</td>
       <td>性别</td>
       <td>成绩</td>
       <td>班级</td>
       <td>电话</td>
       <td>年龄</td>
        <td>操作</td>
    </tr>

    <%
        for(Student s:info){
    %>
    <tr>
        <td><%=s.getSno()%></td>
        <td><%=s.getName()%></td>
        <td><%=s.getPassword()%></td>
        <td><%=s.getSex()%></td>
        <td><%=s.getScore()%></td>
        <td><%=s.getCid()%></td>
        <td><%=s.getPhone()%></td>
        <td><%=s.getAge()%></td>
        <td><a href="updateEdit?id=<%s.getSno();%>">修改</a> ||<a href="delete?id=<%s.getSno();%>">删除</a></td>

    </tr>
    <%
        }
    %>
<tr>
    <td>
        <a href="add.jsp">添加</a>
    </td>
</tr>
</table>
    <div>
        <a href="pageAllInfo?pageNum=1">首页</a>
        <a href="pageAllInfo?pageNum=<%=pageBean.getPageNum()>1?pageBean.getPageNum()-1:1%>">上一页</a>
        <a href="pageAllInfo?pageNum=<%=pageBean.getPageNum()<pageBean.getTotalPages()?pageBean.getPageNum()+1:pageBean.getTotalPages()%>"下一页</a>
        <a href="pageAllInfo?pa">尾页</a>
        第 / 页
    </div>
</div>
</body>
</html>

你的 pageBean 应该是 null ，导致 32行 调用 getName方法 出现空指针异常，你检查这个pageBean的获取逻辑