'How to send an arrayList in Java to HTML (Not JSP)

I created a java application which is connected to a database. The regular java console application part of it works just fine. Now I want to display my Result Set on an HTML web page. BUT I keep getting a 404 error from Ajax via the console on Chrome. Here is my Java code:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.List;
import java.io.IOException;
import java.io.PrintWriter; 
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.fasterxml.jackson.databind.ObjectMapper;

public class EmployeeDao
{
   /*  Database Parameters */
   public List<tickets> viewMyTickets(HttpServletRequest req, HttpServletResponse resp)
   {
       HttpSession  appSession = req.getSession(false); 
       PreparedStatement myStatement = null;
       String userUsername = req.getParameter("username");
       String userPassword = req.getParameter("password");
       String userEmployeeID = req.getParameter("employeeID");
       int userEmployeeID2 = Integer.parseInt(userEmployeeID);
       String usernameSession = appSession.getAttribute("username").toString();
       String userPasswordSession = appSession.getAttribute("password").toString();
       ResultSet myRs;
       tickets activeTickets;
       int userTicketNumber = 0;
       String userTicketsDescription = " ";
       String userTicketsStatus = " ";
       Double userReimbursementAmount = 0.0;
       Timestamp userDateSubmitted = null;
       Timestamp userDateResolved = null;
       String userReimbursementType = " ";
       
       
       if(userUsername.equals(usernameSession ) && userPassword.equals(userPasswordSession) )
       {
           String selectAllEmployeeRequests = "SELECT * FROM tickets WHERE employeeID = ?";
           
           try 
           {
              myStatement = AndreConnection.prepareStatement(selectAllEmployeeRequests);
              myStatement.setInt(1, userEmployeeID2);
              myRs = myStatement.executeQuery();
              List<tickets> employeeTicketsList = new ArrayList<tickets>();
              while (myRs.next()) 
              {
                  userTicketNumber = myRs.getInt("ticketNumber");
                  userTicketsDescription = myRs.getString("ticketsDescription");
                  userTicketsStatus = myRs.getString("ticketsStatus");
                  userReimbursementAmount = myRs.getDouble("reimbursementAmount");
                  userDateSubmitted = myRs.getTimestamp("dateSubmitted");
                  userDateResolved = myRs.getTimestamp("dateResolved");
                  userReimbursementType = myRs.getString("reimbursementType");
                  userEmployeeID2 = myRs.getInt("employeeID");
                  
                  activeTickets = new tickets(userTicketsDescription, userTicketsStatus, userReimbursementAmount, userDateSubmitted, userReimbursementType, userEmployeeID2);
                  employeeTicketsList.add(activeTickets);
              }
              PrintWriter printer = resp.getWriter();
              printer.write(new ObjectMapper().writeValueAsString(employeeTicketsList));
              return employeeTicketsList;
           } 
           catch (SQLException e) 
           {
              e.printStackTrace();
           } 
           catch (IOException e) 
           {
            // TODO Auto-generated catch block
            e.printStackTrace();
           }
            
       }
       else
       {
           try 
           {
             PrintWriter out = resp.getWriter();
             out.println("<html><head><title>Bad Login</title></head><body><h1> Go back and login </h1></body></html>");
             resp.sendRedirect("ERS/index.html");
             
           } 
           catch (IOException e) 
           {
             e.printStackTrace();
           }  
          
       }
    return null;
   
}

Here is my Ajax code:

window.onload = main;

function main()
{    
    ether();
    getInfo();     
}

function ether() 
{ 
    queryString = document.location.search;
    let params = new URLSearchParams(queryString);
    let username = params.get("username");
    document.getElementById("welcome").innerText = "Welcome " + username;
} 

function AndreAjax()
{ 
   document.getElementById('Display').addEventListener('load', getInfo() );
}

function getInfo()
{  
   getRequest();
   return false;
}//end of getNewFile function

function getRequest()
{  
    try
    {
       xhttp = new XMLHttpRequest();    
    }
    catch(err1)
    {
       try
       {
           xhttp = new ActiveXObject("Msxml2.XMLHTTP");
       }
       catch(err2)
       {
           try
           {
               xhttp = new ActiveXObject("Microsoft.XMLHTTP");    
           }
           catch(err3)
           {
               xhttp = false;
           }
       }
    }
    

    if(xhttp)
    {  
       xhttp.onreadystatechange = getServerData;
       
       xhttp.open(`GET`, `http://localhost:9001/ERS/employeeTicketsList` );
       
       xhttp.send();
       setTimeout("getRequest()", 5*1000);
        
    }
    else
    { 
       document.getElementById("Display").innerHTML = "Sorry I could not creat an XMLHttpRequest";   
    }
}//end of getRequest function

function getServerData()
{  
    if(xhttp.readyState==4)
    {
      alert("xhttp.status = " + xhttp.status);
    }

    if(xhttp.readyState==4 && xhttp.status==200)
    {   
       var displayContent = JSON.parse(xhttp.responseText); 
       document.getElementById("Display").innerHTML = displayContent;  
       alert(displayContent);  
    }
    else
    {
       document.getElementById("Display").innerHTML = " waiting Andre";
           
    }
     
    
}

Question: Why can't Ajax find http://localhost:9001/ERS/employeeTicketsList (this is the source of the 404 error in the console in Google Chrome and Firefox) Login for user works just fine, username displays at top of webpage

javaajaxservlets


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Source: Stack Overflow

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