登陆后无法正常跳转了，我不知哪错了，各位帮我看看

studentServlet.class

package com.java.javaweb.student.servlet;

import com.java.javaweb.student.beans.entity.StudentDO;
import com.java.javaweb.student.beans.req.StudentRequest;
import com.java.javaweb.student.beans.res.TableResult;
import com.java.javaweb.student.service.StudentService;
import com.java.javaweb.student.service.impl.StudentServiceImpl;
import com.java.javaweb.student.util.DateUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet(name = "studentServlet",urlPatterns = "/studentServlet")
public class studentServlet extends HttpServlet {
    private StudentService studentService = new StudentServiceImpl();

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doGet(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String type = request.getParameter("type");
        if ("tostudentManage".equals(type)){
            //查询出来学生列表放到request
            String studentName = request.getParameter("studentName");
            String pageNowStr = request.getParameter("pageNow");//当前第几页
            StudentRequest studentRequest = new StudentRequest();
            int pageNow = 1;//默认查询第一页
            if(pageNowStr != null && !"".equals(pageNowStr.trim())){
                pageNow = Integer.parseInt(pageNowStr);
            }
            studentRequest.getPageNow();
            studentRequest.setStudentName(studentName);
            TableResult<StudentDO> tableResult = studentService.queryStudentByPage(studentRequest);
            tableResult.setPageNow(pageNow);
            tableResult.setStudentName(studentName);
            request.setAttribute("tableResult",tableResult);
            //放到request请求域中，并在studentManage.jsp中使用
            request.getRequestDispatcher("/WEB-INF/student/studentManage.jsp").forward(request,response);
        }else if ("toAdd".equals(type)){
            request.getRequestDispatcher("/WEB-INF/student/add.jsp").forward(request,response);
        }
        else if ("add".equals(type)){
           //执行学生的添加
            String studentName = request.getParameter("studentName");
            String no = request.getParameter("no");
            String birthDay = request.getParameter("birthDay");
            StudentDO studentDO = new StudentDO();
            studentDO.setName(studentName);
            studentDO.setNo(no);
            studentDO.setBirthDay(DateUtil.convertStr2Date(birthDay));
           studentService.addStudent(studentDO);
            response.sendRedirect(request.getContextPath()+"/studentServlet?type=tostudentManage");
        }
    }
}

TableResult.class

package com.java.javaweb.student.beans.res;

import com.java.javaweb.student.beans.entity.StudentDO;
import com.java.javaweb.student.util.Constants;

import java.util.List;

/**
 * @author ：Student陈（3091241979@qq.com）
 * @creat time：Created in 2021/12/10 9:21
 * @description：
 * @modified By：
 * @version:
 */
public class TableResult<T> {
    private List<T> data;
    private int totalCount;//共多少条
    private int pageNow;//透传

    public List<T> getData() {
        return data;
    }

    public void setData(List<T> data) {
        this.data = data;
    }

    private String studentName;//透传



    public int getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(int totalCount) {
        this.totalCount = totalCount;
    }

    public int getPageNow() {
        return pageNow;
    }

    public void setPageNow(int pageNow) {
        this.pageNow = pageNow;
    }

    public String getStudentName() {
        return studentName;
    }

    public void setStudentName(String studentName) {
        this.studentName = studentName;
    }

    /*
    总页数
    * */

    public int getpageCount() {
        //总页数
        int pageCount = 0;
        if (totalCount % Constants.PAGE_SIZE == 0){
            pageCount = totalCount/Constants.PAGE_SIZE;
        }else{
            pageCount = totalCount/Constants.PAGE_SIZE +1;
        }
        return pageCount;
    }
}