stockmidlet.java

j2me Demos for example

/*
 *
 * Copyright (c) 2007, 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.
 *  * Redistributions 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 nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package example.stock;

import java.io.*;

import java.util.Timer;
import java.util.TimerTask;

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


/**
 * <p>The MIDlet application class that we'll run for the Stock Demo.</p>
 *
 */
public class StockMIDlet extends MIDlet {
    /**
     * Since there is no support in MIDP/CLDC for floating point numbers,
     * and all of the stock data comes in the form ##.### (usually) then we
     * have to find a way to store the decimals as well as the integer part
     * of the quote data.  Multiplying by the OFFSET will shift the decimal
     * place far enough over to make the number an integer which we can
     * store.  Every time we retrieve quote data from our
     * <code>RecordStore</code> we
     * must make sure that we divide by the OFFSET to correctly display and
     * use the value we actually want.
     */
    private static int OFFSET = 10000; // each 0 is one decimal place

    /**
     * Back <code>Command</code>
     */
    private static final Command BACK_COMMAND = new Command("Back", Command.BACK, 0);

    /**
     * Main Menu <code>Command</code>
     */
    private static final Command MAIN_MENU_COMMAND = new Command("Main", Command.SCREEN, 1);

    /**
     * Done <code>Command</code>
     */
    private static final Command DONE_COMMAND = new Command("Done", Command.OK, 2);

    /**
     * Set <code>Command</code>
     */
    private static final Command SET_COMMAND = new Command("Set", Command.OK, 4);

    /**
     * Exit <code>Command</code>
     */
    private static final Command EXIT_COMMAND = new Command("Exit", Command.STOP, 5);

    /**
     * Calc <code>Command</code>
     */
    private static final Command CALC_COMMAND = new Command("Calc", Command.OK, 6);

    /**
     * The <code>MIDlet</code>'s display object
     */
    Display display = null;

    /**
     * The <code>Ticker</code> that scrolls along the top of the screen
     */
    private Ticker stockTicker = null;

    /**
     * A <code>List</code> of stocks
     */
    private List choose = null;

    /**
     * The Stock Tracker menu
     */
    private List view = null;

    /**
     * The Main menu
     */
    private List menu = null;

    /**
     * The Alert menu
     */
    private List alertList = null;

    /**
     * The Settings menu
     */
    private List settingsList = null;

    /**
     * The 'What If?' <code>Form</code> upon which we enter our query data
     */
    private Form whatif = null;

    /**
     * The <code>Form</code> to display the different update intervals settings
     */
    private Form updatesForm = null;

    /**
     * Used to input a stock symbol
     */
    private TextBox stockSymbolBox = null;

    /**
     * Used to enter the price at which the user wishes to be alerted to the
     * stocks's value
     */
    private TextBox alertPriceBox = null;

    /**
     * The original price the user purchased the stock at, used on the What If?
     * <code>Form</code>
     */
    private TextField origPurchPriceField = null;

    /**
     * The number of shares the users wishes to sell, used on the What If?
     * <code>Form</code>
     */
    private TextField numSharesField = null;

    /**
     * The radio buttons for the update interval time
     */
    private ChoiceGroup updatesChoices = null;

    /**
     * A textual reference to the current menu that is displayed
     * onscreen to
     * allow the <code>StockCommandListener</code> to decide what
     * action to perform upon
     * execution of a command
     */
    private String currentMenu = null;

    /**
     * A reference to the stock that has been chosen from a list of stocks
     * onscreen.  Using this we can extract the correct stock's data from
     * the <code>StockDatabase</code>
     */
    private String stockSymbol = null;

    /**
     * The reference to the <code>StockDatabase</code> that stores
     * the stock data
     */
    private StockDatabase stocks = null;

    /**
     * The reference to the <code>AlertDatabase</code> that stores the alerts
     */
    private AlertDatabase alerts = null;

    /**
     * The server from which the quotes are downloaded
     *
     * NOTE: Currently, only the quote.yahoo.com server is supported
     */
    private String quoteServerURL = "http://quote.yahoo.com/d/quotes.csv?s=";

    /**
     * The format parameter for the quote server to retrieve stock data
     *
     * NOTE: Currently, only this format is supported
     */
    private String quoteFormat = "&f=slc1wop";

    /**
     * The proxy server that must be negotiated
     *
     * NOTE: Proxy server is optional and a blank string indicates that
     *       no proxy should be used
     */

    // Initial default but read from settings file on subsequent runs
    private String proxyURL = null;

    /**
     * The <code>Timer</code> object that refreshes the stock
     * quotes periodically
     */
    private Timer stockRefresh = null;

    /**
     * The <code>TimerTask</code> that the <code>Timer</code>
     * performs periodically.
     * It refreshes the stock quotes
     */
    private StockRefreshTask stockRefreshTask = null;

    /**
     * How often are the stocks' data updated off of the server?
     */

    // Initial default but read from settings file on subsequent runs
    private int refresh_interval = 900000; // 1000 = 1 second
    private boolean firstTime;

    /**
     * <p>Default constructor that is called by the application
     * manager to create a new instance of this <code>MIDlet</code> after
     * which the <code>MIDlet</code> enters the <code>Paused</code> state.</p>
     */
    public StockMIDlet() throws MIDletStateChangeException {
        synchronized (this) {
            // Open the Stocks file
            stocks = new StockDatabase();

            try {
                stocks.open("Stocks");
            } catch (Exception e) {
                try {
                    stocks.cleanUp("Stocks");
                } catch (Exception e2) {
                }
            }

            // Open the Alerts file
            alerts = new AlertDatabase();

            try {
                alerts.open("Alerts");
            } catch (Exception e) {
                try {
                    alerts.cleanUp("Alerts");
                } catch (Exception e2) {
                }
            }

            // Create all the menus and forms
            origPurchPriceField = new TextField("Original Purchase Price:", "", 5, TextField.NUMERIC);
            numSharesField = new TextField("Number Of Shares:", "", 9, TextField.NUMERIC);

            menu = new List("Stock Menu", Choice.IMPLICIT);
            menu.append("Stock Tracker", null);
            menu.append("What If?", null);
            menu.append("Alerts", null);
            menu.append("Settings", null);
            menu.addCommand(EXIT_COMMAND);
            menu.setCommandListener(new StockCommandListener());
            //menu.setTicker(stockTicker);
            whatif = new Form("What If?");
            //whatif.setTicker(stockTicker);
            whatif.append(origPurchPriceField);
            whatif.append(numSharesField);
            whatif.addCommand(BACK_COMMAND);
            whatif.addCommand(CALC_COMMAND);
            whatif.setCommandListener(new StockCommandListener());

            alertList = new List("Alert Menu", Choice.IMPLICIT);
            //alertList.setTicker(stockTicker);
            alertList.append("Add", null);
            alertList.append("Remove", null);
            alertList.addCommand(BACK_COMMAND);
            alertList.setCommandListener(new StockCommandListener());

            settingsList = new List("Settings", Choice.IMPLICIT);
            //settingsList.setTicker(stockTicker);
            settingsList.append("Updates", null);
            settingsList.append("Add Stock", null);
            settingsList.append("Remove Stock", null);
            settingsList.addCommand(BACK_COMMAND);
            settingsList.setCommandListener(new StockCommandListener());

            alertPriceBox = new TextBox("Alert me when stock reaches:", "", 9, TextField.NUMERIC);
            //alertPriceBox.setTicker(stockTicker);
            alertPriceBox.addCommand(DONE_COMMAND);
            alertPriceBox.addCommand(BACK_COMMAND);
            alertPriceBox.setCommandListener(new StockCommandListener());

            updatesForm = new Form("Updates");
            updatesChoices = new ChoiceGroup("Update Interval:", Choice.EXCLUSIVE);
            updatesChoices.append("Continuous", null); // will be 30 seconds
            updatesChoices.append("15 minutes", null); // default for JavaONE
            updatesChoices.append("30 minutes", null);
            updatesChoices.append("1 hour", null);
            updatesChoices.append("3 hours", null);

            switch (refresh_interval) {
            case 30000:
                updatesChoices.setSelectedIndex(0, true);

                break;

            case 1800000:
                updatesChoices.setSelectedIndex(2, true);

                break;

            case 3600000:
                updatesChoices.setSelectedIndex(3, true);

                break;