Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package com.bios.controller.services; import com.bios.model.Bid; import com.bios.model.BidDAO; import com.bios.model.Course; import com.bios.model.CourseDAO; import com.bios.model.MinBidDAO; import com.bios.model.RoundOneBidDAO; import com.bios.model.RoundTwoBidDAO; import com.bios.model.Section; import com.bios.model.SectionDAO; import com.bios.model.SectionStudent; import com.bios.model.SectionStudentDAO; import com.bios.model.Student; import com.bios.model.StudentDAO; import com.bios.utilities.BidComparator; import com.bios.utilities.ConnectionManager; import com.bios.utilities.ErrorMsgComparator; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonParser; import com.google.gson.JsonPrimitive; import is203.JWTException; import is203.JWTUtility; import java.io.IOException; import java.io.PrintWriter; import java.text.DecimalFormat; import java.util.ArrayList; import java.util.HashMap; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; /** * Represents a JSON Web Service for Bid Status * @author Teh Ming Yi */ public class BidStatusService extends HttpServlet { // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code."> /** * Handles the HTTP <code>GET</code> method to determine whether currently * placed bids will be successful at the end of the round. A json object * that contains the live bidding data relating to the bid will be created. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs * */ @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { ConnectionManager manager = new ConnectionManager(); String requestObject = request.getParameter("r"); String token = request.getParameter("token"); ArrayList<String> errorList = new ArrayList<String>(); JsonObject responseObject = new JsonObject(); JsonArray allErrors = new JsonArray(); if (requestObject == null) { errorList.add("missing r"); } else if (requestObject.length() == 0) { errorList.add("blank r"); } if (token == null) { errorList.add("missing token"); } else if (token.length() == 0) { errorList.add("blank token"); } else { try { String result = JWTUtility.verify(token, "abcdefgh12345678"); if (!result.equals("admin")) { errorList.add("invalid token"); } } catch (JWTException e) { // do we need this? // This means not an admin, or token expired errorList.add("invalid username/token"); } } JsonElement jelementRequest = new JsonParser().parse(requestObject); JsonObject json = jelementRequest.getAsJsonObject(); JsonElement crse = json.get("course"); JsonElement sec = json.get("section"); if (crse == null) { errorList.add("missing course"); } else if (crse.getAsString().length() == 0) { errorList.add("blank course"); } if (sec == null) { errorList.add("missing section"); } else if (sec.getAsString().length() == 0) { errorList.add("blank section"); } if (errorList.size() > 0) { errorList.sort(new ErrorMsgComparator()); for (String s : errorList) { allErrors.add(new JsonPrimitive(s)); } responseObject.addProperty("status", "error"); responseObject.add("message", allErrors); response.setContentType("application/json"); response.getWriter().write(responseObject.toString()); return; } String courseID = crse.getAsString(); String sectionID = sec.getAsString(); int round = manager.getBiddingRound(); String status = manager.getBiddingRoundStatus(); // Section that user has selected Section section = SectionDAO.getInstance().findSection(courseID, sectionID); Course course = CourseDAO.getInstance().findCourse(courseID); if (course == null) { allErrors.add(new JsonPrimitive("invalid course")); } else if (course != null && section == null) { allErrors.add(new JsonPrimitive("invalid section")); } if (allErrors.size() > 0) { responseObject.addProperty("status", "error"); responseObject.add("message", allErrors); response.setContentType("application/json"); response.getWriter().write(responseObject.toString()); return; } // How many students have already been enrolled in the section successfully ArrayList<SectionStudent> sectionStudentList = SectionStudentDAO.getInstance() .getSectionStudentListWithID(courseID, sectionID); // Size of the class minus the already enrolled number, which essentially means vacancy int vacancy = section.getSize() - sectionStudentList.size(); // Minimum bid value that has to be shown to user, default is 10 double minBidValue = 10; // This lists the bids that are still pending approval in round 2, and contains the bids // that user has selected, and these bids are sorted from highest to lowest ArrayList<Bid> allBids = BidDAO.getInstance().getPendingBidsWithID(courseID, sectionID); // ArrayList<Bid> allBids= null; // if (round == 1 && status.equals("started")){ // allBids = BidDAO.getInstance().getBidList(); // } else if (status.equals("stopped") && round == 1){ // allBids = RoundOneBidDAO.getInstance().getBidList(); // } else if(round == 2 && status.equals("started")){ // allBids = BidDAO.getInstance().getPendingBids(); // } else{ // allBids = RoundTwoBidDAO.getInstance().getBidList(); // } allBids.sort(new BidComparator()); // This JsonObject is to be used as the reponse to the user JsonObject object = new JsonObject(); object.addProperty("status", "success"); DecimalFormat df = new DecimalFormat("0.00"); JsonArray arrayOfBids = new JsonArray(); if (round == 1 && status.equals("started")) { object.addProperty("vacancy", section.getSize()); if (section.getSize() > allBids.size() && allBids.size() > 0) { minBidValue = allBids.get(allBids.size() - 1).getAmount(); } else if (allBids.size() >= section.getSize()) { minBidValue = allBids.get(section.getSize() - 1).getAmount(); } object.addProperty("min-bid-amount", minBidValue); for (Bid bid : allBids) { JsonObject innerObject = new JsonObject(); Student stud = StudentDAO.getInstance().retrieve(bid.getUserID()); innerObject.add("userid", new JsonPrimitive(bid.getUserID())); innerObject.add("amount", new JsonPrimitive(bid.getAmount())); String result = df.format(stud.geteDollar()); double eDollar = Double.parseDouble(result); innerObject.add("balance", new JsonPrimitive(eDollar)); innerObject.add("status", new JsonPrimitive("pending")); arrayOfBids.add(innerObject); } } else if (round == 1 && status.equals("stopped")) { object.addProperty("vacancy", section.getSize() - BidDAO.getInstance().getSuccessfulBidsWithID(courseID, sectionID).size()); allBids = BidDAO.getInstance().getBids(courseID, sectionID); if (allBids.size() >= vacancy && vacancy != 0) { // should this be >=? wha if vacancy==0? minBidValue = allBids.get(vacancy - 1).getAmount(); } else if (allBids.size() < vacancy && allBids.size() > 0) { minBidValue = allBids.get(allBids.size() - 1).getAmount(); } object.addProperty("min-bid-amount", minBidValue); allBids = BidDAO.getInstance().getBids(courseID, sectionID); for (Bid bid : allBids) { JsonObject innerObject = new JsonObject(); Student stud = StudentDAO.getInstance().retrieve(bid.getUserID()); innerObject.add("userid", new JsonPrimitive(bid.getUserID())); innerObject.add("amount", new JsonPrimitive(bid.getAmount())); String result = df.format(stud.geteDollar()); double eDollar = Double.parseDouble(result); innerObject.add("balance", new JsonPrimitive(eDollar)); innerObject.add("status", new JsonPrimitive(bid.getStatus())); arrayOfBids.add(innerObject); } } else if (round == 2 && status.equals("started")) { object.addProperty("vacancy", vacancy); // This is to re-compute the minimum bid value // if (allBids.size() >= vacancy && vacancy != 0) { // should this be >=? wha if vacancy==0? // minBidValue = allBids.get(vacancy - 1).getAmount() + 1; // } // This allows us to store the minimum bids, and also to persist the bids such that it stores the min bid amount if (MinBidDAO.getInstance().updateMinBid(courseID + "-" + sectionID, minBidValue)) { // Bid was updated successfully object.addProperty("min-bid-amount", minBidValue); } else { object.addProperty("min-bid-amount", MinBidDAO.getInstance().getValue(courseID + "-" + sectionID)); } for (int i = 0; i < allBids.size(); i++) { Bid bid = allBids.get(i); JsonObject innerObject = new JsonObject(); Student stud = StudentDAO.getInstance().retrieve(bid.getUserID()); innerObject.add("userid", new JsonPrimitive(bid.getUserID())); innerObject.add("amount", new JsonPrimitive(bid.getAmount())); String result = df.format(stud.geteDollar()); double eDollar = Double.parseDouble(result); innerObject.add("balance", new JsonPrimitive(eDollar)); // If there are vacancies still if (vacancy >= allBids.size()) { innerObject.add("status", new JsonPrimitive("success")); } else if (allBids.size() > vacancy) { // If this bid is still within the vacancy requirements if (i <= vacancy) { Bid firstFailedBid = allBids.get(vacancy); if (bid.getAmount() == firstFailedBid.getAmount()) { innerObject.add("status", new JsonPrimitive("fail")); } else { innerObject.add("status", new JsonPrimitive("success")); } } else if (i > vacancy) { //what if vacancy+1's bid amout innerObject.add("status", new JsonPrimitive("fail")); } } arrayOfBids.add(innerObject); } } else { object.addProperty("vacancy", section.getSize() - BidDAO.getInstance().getSuccessfulBidsWithID(courseID, sectionID).size()); allBids = BidDAO.getInstance().getSuccessfulBidsWithID(courseID, sectionID); allBids.sort(new BidComparator()); minBidValue = allBids.get(allBids.size() - 1).getAmount(); object.addProperty("min-bid-amount", minBidValue); for (Bid bid : allBids) { JsonObject innerObject = new JsonObject(); Student stud = StudentDAO.getInstance().retrieve(bid.getUserID()); innerObject.add("userid", new JsonPrimitive(bid.getUserID())); innerObject.add("amount", new JsonPrimitive(bid.getAmount())); String result = df.format(stud.geteDollar()); double eDollar = Double.parseDouble(result); innerObject.add("balance", new JsonPrimitive(eDollar)); innerObject.add("status", new JsonPrimitive(bid.getStatus())); arrayOfBids.add(innerObject); } } object.add("students", arrayOfBids); response.setContentType("application/json"); response.getWriter().write(object.toString()); } /** * Handles the HTTP <code>POST</code> method. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { } /** * Returns a short description of the servlet. * * @return a String containing servlet description */ @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }