Listing of Servlet (Controller): AirlineTicketBookingServlet (Web Component)
| You learned about servlets on Days 3 and 4. Listing C.10 shows the detailed code for the controller servlet described in Chapter 4 for the MVC application. Place these files in the directory called web_components_src, discussed on Day 16. Listing C.10 AirlineTicketBookingServlet /********************************************************************************* * Class Name:AirlineTicketBookingServlet.java * Description:Controller servlet for the MVC Application * @author Mandar S. Chitnis, Pravin S. Tiwari, Lakshmi AM. @version 11.5 * Copyright (c) by Sams Publishing. All Rights Reserved. **********************************************************************************/ package com.sams.learnweblogic7.airlines.servlet; import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import java.util.*; import javax.naming.*; import javax.rmi.*; import javax.ejb.*; import com.sams.learnweblogic7.airlines.businessobject.*; import com.sams.learnweblogic7.airlines.constants.*; import com.sams.learnweblogic7.airlines.sessionbean.*; import com.sams.learnweblogic7.airlines.exception.*; public class AirlineTicketBookingServlet extends HttpServlet { String[][] jspMappings= {{"*","1","/ViewAvailFlightsPage"},{"*","2","/Login"},{"1","3","/Login"}, {"3","4","/DisplayConfirmation"},{"9","4","/DisplayConfirmation"}, {"4","7","/Welcome"},{"4","6","/Message"},{"6","10","/Welcome"}, {"3","5","/RegisterUserProfilePage"},{"2","5","/RegisterUserProfilePage"}, {"5","9","/Login"},{"2","4","/ViewUserProfilePage"},{"4","8","/Welcome"}, {"4","11","/ViewFlightDetails"},{"11","12","/Welcome"}}; ServletContext sc; private String sep=System.getProperty( "line.separator" ); /**************************************************************************** * Method Name : getServletInfo * Input Parameters : none * Return Parameters : java.lang.String * Exceptions thrown : None * Description : This method provides information about the servlet's functions ****************************************************************************/ public String getServletInfo() { return "Airline Booking System's Controller servlet"; } /*************************************************************************** * Method Name : init * Input Parameters : ServletConfig * Return Parameters : none * Exceptions : none * Description : This method is used to perform functions which should be carried over the entire life of the servlet. **************************************************************************/ public void init(ServletConfig config) throws ServletException{ super.init(config); sc=getServletConfig().getServletContext(); } /************************************************************************** * Method Name : doGet * Input Parameters : HttpServletRequest, HttpServletResponse * Return Parameters : none * Exceptions : javax.servlet.ServletException, java.io.IOException * Description : This method is called by the Get method of an http request. * Here, call the doPost method and pass the request * and response objects to the doPost method. **************************************************************************/ public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doPost(req,resp); } public void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { try { //STEP-1 => Get the MVCAppValueObject from the HttpServletRequest MVCAppValueObject inputValueObject= MVCAppValueFactory.getMVCAppValueObject(req); //STEP-2 => Call the business method (if required) // and get the output MVCAppValueObject MVCAppValueObject outputValueObject= businessMethod(inputValueObject, req); //STEP-3 => Pass the outputValueObject to the respective JSP // based on action id callJSP(req, resp, outputValueObject); }catch(GenericException ge){ ge.printStackTrace(); req.setAttribute(MVCConstants.OUTPUT_MVCVALUEOBJECT, ge); RequestDispatcher rd=sc.getRequestDispatcher("/ErrorPage"); rd.forward(req,resp); } catch(Exception e){ e.printStackTrace(); req.setAttribute(MVCConstants.OUTPUT_MVCVALUEOBJECT, new GenericException(e)); RequestDispatcher rd=sc.getRequestDispatcher("/ErrorPage"); rd.forward(req,resp); } finally { //add any other code that you feel appropriate System.out.println("inside finally of doPost"); } } //STEP-2 => Call the business method (if required) and get the output // MVCAppValueObject public MVCAppValueObject businessMethod(MVCAppValueObject inputValueObject, HttpServletRequest req) throws Exception { MVCAppValueObject outputValueObject=new MVCAppValueObject(); CustomerServiceAgentHome customerServiceAgentHomeObj=null; CustomerServiceAgentInterface customerServiceAgentRemoteObj=null; TicketSalesAgentHome ticketSalesAgentHomeObj=null; TicketSalesAgentInterface ticketSalesAgentRemoteObj=null; HttpSession httpSessionObj=null; Handle statefulBeanHandle=null; String errorDesc=""; try { // Get the Previous and Current Action Ids String previousActionID=(String)inputValueObject. get(JspFieldConstants.PREVIOUS_ACTION_ID); String strActionID=(String)inputValueObject. get(JspFieldConstants.ACTION_ID); int actionID=Integer.parseInt(strActionID); switch(actionID) { // searching the list of flights available for a location and a date case JspFieldConstants.SEARCH_ACTION_ID : customerServiceAgentHomeObj=lookupCustomerServiceAgentHome(); customerServiceAgentRemoteObj=(CustomerServiceAgentInterface) PortableRemoteObject.narrow (customerServiceAgentHomeObj.create(), CustomerServiceAgentInterface.class); outputValueObject= customerServiceAgentRemoteObj.viewAvailableFlights (inputValueObject); String day=(String)inputValueObject. get(JspFieldConstants.CHECK_AVAIL_FLIGHTS_PAGE_DEP_DAY); String month=(String)inputValueObject. get(JspFieldConstants.CHECK_AVAIL_FLIGHTS_PAGE_DEP_MONTH); String year=(String)inputValueObject. get(JspFieldConstants.CHECK_AVAIL_FLIGHTS_PAGE_DEP_YEAR); Calendar buildSqlDate=Calendar.getInstance(); buildSqlDate.set(Integer.parseInt(year), Integer.parseInt(month), Integer.parseInt(day)); java.sql.Date bookDate= new java.sql.Date(buildSqlDate.getTime().getTime()); outputValueObject.put(JspFieldConstants. DISPLAY_AVAIL_FLIGHTS_PAGE_DEP_DATE, bookDate.toString()); outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; // viewing the profile of the existing user based on user name and password case JspFieldConstants.VIEW_PROFILE_ACTION_ID : outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; // user selects a particular flight he wants to buy from the list // of available flights case JspFieldConstants.BOOK_ACTION_ID : // now since we are not doing any business operations we simply // return the inputValueObject. outputValueObject=inputValueObject; return outputValueObject; case JspFieldConstants.LOGIN_ACTION_ID : customerServiceAgentHomeObj=lookupCustomerServiceAgentHome(); customerServiceAgentRemoteObj=(CustomerServiceAgentInterface) PortableRemoteObject.narrow(customerServiceAgentHomeObj. create(),CustomerServiceAgentInterface.class); MVCAppValueObject userProfileValueObject= customerServiceAgentRemoteObj.authenticateUser (inputValueObject); httpSessionObj=req.getSession(true); //if the user has come from the view profile page, then do this if((Integer.parseInt(previousActionID)) == 2) { // time to create a session (STATEFULL SESSION BEAN) for the user ticketSalesAgentHomeObj=lookupTicketSalesAgentHome(); ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow(ticketSalesAgentHomeObj. create(),TicketSalesAgentInterface.class); // STEP (1) : put the user information in session for future use ticketSalesAgentRemoteObj.putUserInformation (userProfileValueObject); outputValueObject=userProfileValueObject; } else {//the user has come here after selecting flight details // time to create a session (STATEFULL SESSION BEAN) for the user ticketSalesAgentHomeObj=lookupTicketSalesAgentHome(); ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow(ticketSalesAgentHomeObj. create(),TicketSalesAgentInterface.class); // ******* now do three things here .... // STEP (1) put the user informtion in session for future use // STEP (2) add the ticket details in the user session // STEP (3) get all the informtion from the session //(user information that is set in STEP 1 and ticket informtion //from STEP 2 // STEP (1) : put the user informtion in session for future use ticketSalesAgentRemoteObj.putUserInformation (userProfileValueObject); // STEP (2) add the ticket details in the user session ticketSalesAgentRemoteObj.addOrder(inputValueObject); // STEP (3) get all the informtion from the session outputValueObject=ticketSalesAgentRemoteObj.getSessionData(); } // Now you need to put the handle of this STATEFUL SESSION BEAN // in the HttpSession statefulBeanHandle=ticketSalesAgentRemoteObj.getHandle(); // this handle is stored in HttpSession httpSessionObj.setAttribute(MVCConstants.SESSION_HANDLE, statefulBeanHandle); outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; case JspFieldConstants.REGISTER_ACTION_ID : // now since you are not doing any business operations, simply // return the inputValueObject outputValueObject=inputValueObject; outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; case JspFieldConstants.DISPLAY_CONFIRMED_FLIGHTS_CONFIRM_ACTION_ID : // now that user has CONFIRMED THE TICKET, COMMIT the // transaction. Also, the order is removed from the user session as // it is already bought by the user and the new orders will // be added to user session if he/she wishes to buy more httpSessionObj=req.getSession(false); if(httpSessionObj == null) { errorDesc="There seems to be some problem accessing your profile .... Please try again" + sep; errorDesc=errorDesc + " Sorry for the inconvenience "; throw new GenericException(errorDesc); }else { statefulBeanHandle= (Handle)httpSessionObj.getAttribute (MVCConstants.SESSION_HANDLE);ticketSalesAgentRemoteObj= (TicketSalesAgentInterface) PortableRemoteObject.narrow (statefulBeanHandle. getEJBObject(), TicketSalesAgentInterface.class); outputValueObject=ticketSalesAgentRemoteObj.confirmBooking(); } outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; case JspFieldConstants.DISPLAY_CONFIRMED_FLIGHTS_CANCEL_ACTION_ID : httpSessionObj=req.getSession(false); if(httpSessionObj == null) { errorDesc="There seems to be some problem accessing your profile .... Please try again" + sep; errorDesc=errorDesc + " Sorry for the inconvenience "; throw new GenericException(errorDesc); }else { statefulBeanHandle= (Handle)httpSessionObj.getAttribute (MVCConstants.SESSION_HANDLE); ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow(statefulBeanHandle. getEJBObject(), TicketSalesAgentInterface.class); // remove the ticket order from the session and rollback the // transaction, if required ticketSalesAgentRemoteObj.cancelBooking(); } outputValueObject=inputValueObject; return outputValueObject; case JspFieldConstants.VIEW_USER_PROFILE_PAGE_BACK_TO_SEARCH_ ACTION_ID: case JspFieldConstants.VIEW_USER_PROFILE_PAGE_LOGOUT_ACTION_ID: httpSessionObj=req.getSession(true); if(httpSessionObj.isNew()) { //do nothing }else { statefulBeanHandle= (Handle)httpSessionObj.getAttribute (MVCConstants.SESSION_HANDLE); ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject. narrow(statefulBeanHandle.getEJBObject(), TicketSalesAgentInterface.class); // end the session if (ticketSalesAgentRemoteObj != null) { ticketSalesAgentRemoteObj.remove(); } // you have already ended session for stateful session bean // now invalidate the session of the user from the servlet weblogic.servlet.security.ServletAuthentication. invalidateAll(req); } outputValueObject=inputValueObject; return outputValueObject; case JspFieldConstants. VIEW_USER_PROFILE_PAGE_FLIGHT_DETAILS_ACTION_ID : httpSessionObj=req.getSession(false); if(httpSessionObj == null) { errorDesc="There seems to be some problem accessing your profile .... Please try again" + sep; errorDesc=errorDesc + " Sorry for the inconvenience "; throw new GenericException(errorDesc); }else { statefulBeanHandle=(Handle)httpSessionObj. getAttribute(MVCConstants.SESSION_HANDLE); ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow(statefulBeanHandle. getEJBObject(), TicketSalesAgentInterface.class); outputValueObject=ticketSalesAgentRemoteObj.getUserTicketInfo(); } outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; case JspFieldConstants.REGISTER_USER_PROFILE_PAGE_REGISTER_SUBMIT_ ACTION_ID: customerServiceAgentHomeObj=lookupCustomerServiceAgentHome(); CustomerServiceAgentInterface customerServiceAgentInterfaceObj= (CustomerServiceAgentInterface)PortableRemoteObject. narrow(customerServiceAgentHomeObj.create(), CustomerServiceAgentInterface.class); customerServiceAgentInterfaceObj.createUserProfile(inputValueObject); // after user profile is created you have nothing to return, // so send the inputdata itself outputValueObject=inputValueObject; return outputValueObject; case JspFieldConstants.THANK_YOU_PAGE_ACTION_ID: //when the user clicks on OK button, remove his session from //session object and then call on the first jsp httpSessionObj=req.getSession(false); if(httpSessionObj == null) { // do nothing }else { weblogic.servlet.security.ServletAuthentication.invalidateAll(req); } outputValueObject.put(JspFieldConstants.ACTION_ID, strActionID); outputValueObject.put(JspFieldConstants.PREVIOUS_ACTION_ID, previousActionID); return outputValueObject; default: } }catch(GenericException exp) { httpSessionObj=req.getSession(false); if(httpSessionObj==null) { // do nothing }else { statefulBeanHandle=(Handle)httpSessionObj. getAttribute(MVCConstants.SESSION_HANDLE); if (statefulBeanHandle!= null) { ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow (statefulBeanHandle.getEJBObject(), TicketSalesAgentInterface.class); ticketSalesAgentRemoteObj.remove(); } // you have already ended session for stateful session bean // now invalidate the session of the user from the servlet also weblogic.servlet.security.ServletAuthentication.invalidateAll(req); } throw exp; }catch(Exception exp) { httpSessionObj=req.getSession(true); if(httpSessionObj.isNew()) { // you may want to throw an exception here }else { statefulBeanHandle= (Handle)httpSessionObj.getAttribute (MVCConstants.SESSION_HANDLE); if (statefulBeanHandle != null) { ticketSalesAgentRemoteObj=(TicketSalesAgentInterface) PortableRemoteObject.narrow (statefulBeanHandle.getEJBObject(), TicketSalesAgentInterface.class); ticketSalesAgentRemoteObj.remove(); } // you have already ended session for stateful session bean // now invalidate the session of the user from the servlet too weblogic.servlet.security.ServletAuthentication.invalidateAll(req); } throw new GenericException(exp); } return outputValueObject; } public void callJSP(HttpServletRequest req, HttpServletResponse resp, MVCAppValueObject outputValueObject) throws Exception { // get the Previous and Current Action Id's String previousActionID=(String)outputValueObject. get(JspFieldConstants.PREVIOUS_ACTION_ID); String presActionID=(String)outputValueObject. get(JspFieldConstants.ACTION_ID); String jspToBeCalled=getNextJSPToBeCalled(previousActionID, presActionID); req.setAttribute(MVCConstants.OUTPUT_MVCVALUEOBJECT, outputValueObject); RequestDispatcher rd=sc.getRequestDispatcher(jspToBeCalled); rd.forward(req,resp); } /** * Look up the Airline bean's home interface using JNDI. */ private CustomerServiceAgentHome lookupCustomerServiceAgentHome() throws NamingException { Hashtable h=new Hashtable(); h.put(Context.INITIAL_CONTEXT_FACTORY, MVCConstants. WEBLOGIC_INITIAL_CONTEXT_FACTORY); h.put(Context.PROVIDER_URL, MVCConstants.WEBLOGIC_PROVIDER_URL); Context ctx=new InitialContext(h); try { Object home=(CustomerServiceAgentHome) ctx.lookup("CustomerServiceAgentBean"); return (CustomerServiceAgentHome)PortableRemoteObject. narrow(home, CustomerServiceAgentHome.class); }catch (NamingException ne) { System.out.println("Unable to lookup the EJBHome.Verify the ejb JNDI name CustomerServiceAgentHome on the WebLogic server"); throw ne; } } /** * Look up the TicketSalesAgent bean's home interface using JNDI. */ private TicketSalesAgentHome lookupTicketSalesAgentHome() throws NamingException { Hashtable h=new Hashtable(); h.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory"); h.put(Context.PROVIDER_URL, "t3://localhost:7001"); Context ctx=new InitialContext(h); try { Object home=(TicketSalesAgentHome)ctx.lookup("TicketSalesAgent"); return (TicketSalesAgentHome) PortableRemoteObject.narrow(home, TicketSalesAgentHome.class); } catch (NamingException ne) { System.out.println("Unable to lookup the EJBHome. Verify the ejb JNDI name TicketSalesAgentHome on the WebLogic server"); throw ne; } } private String getNextJSPToBeCalled(String prevActionId, String presActionId) { for(int i=0; i < jspMappings.length; i++) { if(jspMappings[i][0].equals(prevActionId)) { for(int j=1;j<jspMappings[i].length;j++) { if(jspMappings[i][j].equals(presActionId)) { return jspMappings[i][j+1]; } } } }//end of for return "FAILED"; } } |
Sams Teach Yourself BEA WebLogic Server 7.0 in 21 Days
ISBN: 0672324334
EAN: 2147483647
EAN: 2147483647
Year: 2002
Pages: 339
Pages: 339