session.java

值得一看的J2ME_J2EE结合使用经典例程

/*
 * Copyright 1999-2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the
 *   distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN
 * OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR
 * FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR
 * PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF
 * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that Software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of
 * any nuclear facility.
 */

package st;

import java.io.*;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import javax.microedition.rms.*;

import shared.MessageConstants;

/**
 * Helper for managing the shopping session with the server.
 */
public class Session implements Runnable {

    /*
     * Note: Each method that connects with the server calls back to 
     * the SmartTicket MIDlet:
     *
     * 1) updateGauge() as needed to update the progress bar for the user.
     * 2) stopLoading() or stopLoading(Exception) to indicate the operation
     *    is done.
     */
    
    byte message;

    // The name of the MIDlet's record store.
    static final String RECORD_STORE_NAME = "SmartTicket";
    static final String MESSAGE_STORE_NAME = "l10n_data";

    
    SmartTicket smartTicket;
    RecordStore recordStore;
    
    // Cache variable for preview mode.
    byte previewMode;
    
    // Cache variable for size of rows in seating plan.
    int rowSize;

    public Session(SmartTicket st) {
        smartTicket = st;
    }

    /**
     * run method for this session - from here we call the individual
     * methods that service the requests
     */
    public void run() {
	switch (message) {
	case MessageConstants.CREATE_USER:
	    createUser(smartTicket.accountForm.getUsername(),
		       smartTicket.accountForm.getPassword(),
		       smartTicket.accountForm.getZipCode(),
		       smartTicket.accountForm.getCreditCard(),
		       smartTicket.accountForm.getPreviewMode());
	    break;
	case MessageConstants.LOGIN_USER:
	    login();
	    break;
	case MessageConstants.DISPLAY_LOCALES:
	    loadLocales(smartTicket.localeList);
	    break;
	case MessageConstants.LOAD_MESSAGES:
	    loadMessages(smartTicket.localeList.getLocaleID());
	    break;
	case MessageConstants.DISPLAY_MOVIES:
	    loadMovies(smartTicket.movieList);
	    break;
	case MessageConstants.DISPLAY_LOCATIONS:
	    loadLocations(smartTicket.locationList, 
			  smartTicket.movieList.getMovieID()); 
	    break;
	case MessageConstants.DISPLAY_SHOWTIMES:
           loadShowtimes(smartTicket.showtimeList,
			 smartTicket.movieList.getMovieID(),
			 smartTicket.locationList.getLocationID());
	   
	    break;
	case MessageConstants.DISPLAY_SEATINGPLAN:
	    loadSeatingPlan(smartTicket.seatingCanvas,
			    smartTicket.showtimeList.getShowID(),
			    smartTicket.movieList.getMovieTitle(),
			    smartTicket.showtimeList.getShowtime());
	    break;
	case MessageConstants.DISPLAY_POSTER:
	    loadPoster(smartTicket.posterCanvas, 
		       smartTicket.posterURL + 
		       smartTicket.movieList.getPosterUrl()); 
	    break;
	case MessageConstants.RESERVE_SEATS:
	    reserveSeats(smartTicket.confirmForm, 
			 smartTicket.seatingCanvas.getSelectedSeats(),
			 smartTicket.movieList.getMovieTitle(),
			 smartTicket.showtimeList.getShowtime());
	    break;
	case MessageConstants.CONFIRM_SEATS:
	    confirmSeats(smartTicket.confirmForm.getCreditCardCheck());
	    break;
	case MessageConstants.CANCEL_SEATS:
	    cancelSeats();
	    break;
	default:
	}
    }

    /**
     * Open the session.
     *
     * Remember to call close() when you are done.
     */
    public void open() {
        try {
            recordStore = RecordStore.openRecordStore(RECORD_STORE_NAME, true);
        }
        catch (RecordStoreException rse) {
            // Do nothing.
        }
    }
    
    /**
     * Indicate whether the session is for a new user (one who doesn't have
     * an account).
     */
    public boolean isNewUser() {
        try {
            return (recordStore.getNumRecords() == 0);
        }
        catch (RecordStoreException rse) {
            return true;
        }
    }

    /**
     * Close the session.
     *
     * The session should have been opened using open().
     */
    public void close() {
        try {
            recordStore.closeRecordStore();
        }
        catch (RecordStoreException rse) {
            // Do nothing.
        }
    }

    /* Messages to server. */
    
    /**
     * Login to server.
     */
    public void login() {
        HttpConnection conn = null;
        DataInputStream in = null;
        
        try {
            if (recordStore.getNumRecords() == 0) {
                throw new ApplicationException(
		   MessageConstants.USER_NOT_FOUND_ERROR);
            }
            
            // Load the account from local store.
            byte[] record = recordStore.getRecord(1);
            in = new DataInputStream(new ByteArrayInputStream(record));
            String userID = in.readUTF();
            String password = in.readUTF();
            int zipCode = in.readInt();
            previewMode = (byte)in.read();

            // Send the login information to the server.
            smartTicket.updateGauge(GaugeForm.GAUGE_MAX/3);
            String message = MessageConstants.LOGIN_USER + 
		"^" + userID + "," + password;
            conn = open(smartTicket.getBaseServletURL(), message);
            in = conn.openDataInputStream();
            smartTicket.updateGauge(2*GaugeForm.GAUGE_MAX/3);
            smartTicket.servlet = in.readUTF();
            smartTicket.updateGauge(GaugeForm.GAUGE_MAX);
            smartTicket.stopLoading();
        } 
        catch (Exception e) {
            smartTicket.stopLoading(e);
        }
        finally {
            close(conn, in);
        }
    }

    /**
     * Load the list of locales available for this application.
     *
     * @param  ll  the list to populate with locale data.
     */
    public void loadLocales(LocaleList ll) {
	HttpConnection conn = null;
	DataInputStream in = null;
	
	try {
	    smartTicket.updateGauge(GaugeForm.GAUGE_MAX/3);
	    String message = MessageConstants.DISPLAY_LOCALES + "^";
	    conn = open(smartTicket.servlet, message);
	    in = conn.openDataInputStream();
	    smartTicket.updateGauge(2*GaugeForm.GAUGE_MAX/3);
	    int count = in.readInt();
	    ll.init(count);
            for (int i = 0; i != count; i++) {
                ll.addLocale(in.readInt(), in.readUTF());
            }

	    smartTicket.updateGauge(GaugeForm.GAUGE_MAX);
            smartTicket.stopLoading();   
	} catch (Exception e) {
	    smartTicket.stopLoading(e);
	} finally {
	    close(conn, in);
	}
	
    }

    /**
     * Load into the record store the localized messages for the
     * locale with the given ID.  
     */
    public void loadMessages(int localeID) {
	HttpConnection conn = null;
	DataInputStream in = null;
	RecordStore rs = null;

	try {
	    rs = openMessageStore(true);
	    byte [] record = 
		smartTicket.localeList.getLocale().getBytes();
	    if (rs.getNumRecords() > 0) {
		if (smartTicket.localeList.getLocale().equals(
		    new String(rs.getRecord(1)))) {
		    smartTicket.updateGauge(GaugeForm.GAUGE_MAX);
		    smartTicket.stopLoading();
		    return;
		} else {
		    rs.setRecord(1, record, 0, record.length);
		}
	    } else {
		rs.addRecord(record, 0, record.length);
	    }
	    
	    /*
	     * If the selected localed is not the default and not
	     * the current locale download the messages
	     */
	    if (localeID > 0) {
		
		String message = MessageConstants.LOAD_MESSAGES + 
		    "^" + localeID;
		conn = open(smartTicket.servlet, message);
		in = conn.openDataInputStream();
		smartTicket.updateGauge(2*GaugeForm.GAUGE_MAX/3);
		
		// read the messages
		record = in.readUTF().getBytes();
		if (rs.getNumRecords() > 1) {
		    rs.setRecord(2, record, 0, record.length);
		} else {
		    rs.addRecord(record, 0, record.length);
		}
	    }
	    smartTicket.updateGauge(GaugeForm.GAUGE_MAX);
	    smartTicket.stopLoading();
		
	} catch (Exception e) {
	    smartTicket.stopLoading(e);
	} finally {
	    close(conn, in);
	    if (rs != null) {
		try {
		    rs.closeRecordStore();
		} catch (RecordStoreException rse) {
		    // ignore
		}
	    }
	}
    }
    
    /**
     * Create a new user account.
     *
     * This method saves some information locally and some information on the
     * server.
     *
     * @param  userID  the user name.
     * @param  password  the user's password.
     * @param  zipCode  the user's zipCode.
     * @param  creditCard  the user's credit card number.
     * @param  previewMode  the user's preview mode preference.
     */
    public void createUser(String userID, String password, int zipCode,
                           String creditCard, byte previewMode) 
    {
        HttpConnection conn = null;
        DataInputStream in = null;
        
        try {
            // Send the account information to the server.
            smartTicket.updateGauge(GaugeForm.GAUGE_MAX/3);
            String message = MessageConstants.CREATE_USER + 
		"^" + userID + "," + password
                + "," + zipCode + "," + creditCard;
            conn = open(smartTicket.servlet, message);
            in = conn.openDataInputStream();
            smartTicket.updateGauge(2*GaugeForm.GAUGE_MAX/3);
            smartTicket.servlet = in.readUTF();

            // Save the account to the local store.
            ByteArrayOutputStream bout = new ByteArrayOutputStream();
            DataOutputStream out = new DataOutputStream(bout);
            out.writeUTF(userID);
            out.writeUTF(password);
            out.writeInt(zipCode);
            out.write((byte)previewMode);
            byte[] record = bout.toByteArray();
            if (recordStore.getNumRecords() > 0) {
                recordStore.setRecord(1, record, 0, record.length);
            } else {
                recordStore.addRecord(record, 0, record.length);
            }

            smartTicket.updateGauge(GaugeForm.GAUGE_MAX);
            smartTicket.stopLoading();
        } catch (Exception e) {
            smartTicket.stopLoading(e);
        } finally {
            close(conn, in);
        }
    }