Java/J2ME/Ticker
Quotes MIDlet
<source lang="java">
/* Learning Wireless Java Help for New J2ME Developers By Qusay Mahmoud ISBN: 0-596-00243-2
- /
import java.util.Enumeration; import javax.microedition.rms.*; import javax.microedition.lcdui.*; import javax.microedition.midlet.*; import javax.microedition.io.*; import java.io.*; public class QuotesMIDlet extends MIDlet implements CommandListener {
Display display = null;
List menu = null; // main menu
List choose = null;
TextBox input = null;
Ticker ticker = new Ticker("Database Application");
String quoteServer =
"http://quote.yahoo.ru/d/quotes.csv?s=";
String quoteFormat = "&f=slc1wop"; // The only quote format supported
static final Command backCommand = new Command("Back", Command.BACK, 0);
static final Command mainMenuCommand = new Command("Main", Command.SCREEN, 1);
static final Command saveCommand = new Command("Save", Command.OK, 2);
static final Command exitCommand = new Command("Exit", Command.STOP, 3);
String currentMenu = null;
// Stock data
String name, date, price;
// record store
StockDB db = null;
public QuotesMIDlet() { // constructor
}
// start the MIDlet
public void startApp() throws MIDletStateChangeException {
display = Display.getDisplay(this);
// open a db stock file
try {
db = new StockDB("mystocks");
} catch(Exception e) {}
menu = new List("Stocks Database", Choice.IMPLICIT);
menu.append("List Stocks", null);
menu.append("Add A New Stock", null);
menu.addCommand(exitCommand);
menu.setCommandListener(this);
menu.setTicker(ticker);
mainMenu();
}
public void pauseApp() {
display = null;
choose = null;
menu = null;
ticker = null;
try {
db.close();
db = null;
} catch(Exception e) {}
}
public void destroyApp(boolean unconditional) {
try {
db.close();
} catch(Exception e) {}
notifyDestroyed();
}
void mainMenu() {
display.setCurrent(menu);
currentMenu = "Main";
}
// Construct a running ticker
// with stock names and prices
public String tickerString() {
StringBuffer ticks = null;
try {
RecordEnumeration e = db.enumerate();
ticks = new StringBuffer();
while(e.hasNextElement()) {
String stock1 = new String(e.nextRecord());
ticks.append(Stock.getName(stock1));
ticks.append(" @ ");
ticks.append(Stock.getPrice(stock1));
ticks.append(" ");
}
} catch(Exception ex) {}
return (ticks.toString());
}
// Add a new stock to the record store
// by calling StockDB.addNewStock()
public void addStock() {
input = new TextBox("Enter a Stock Name:", "", 5, TextField.ANY);
input.setTicker(ticker);
input.addCommand(saveCommand);
input.addCommand(backCommand);
input.setCommandListener(this);
input.setString("");
display.setCurrent(input);
currentMenu = "Add";
}
// Connect to quote.yahoo.ru and
// retrieve the data for a given
// stock symbol.
public String getQuote(String input) throws IOException, NumberFormatException {
String url = quoteServer + input + quoteFormat;
StreamConnection c = (StreamConnection)Connector.open(
url, Connector.READ_WRITE);
InputStream is = c.openInputStream();
StringBuffer sb = new StringBuffer();
int ch;
while((ch = is.read()) != -1) {
sb.append((char)ch);
}
return(sb.toString());
}
// List the stocks in the record store
public void listStocks() {
choose = new List("Choose Stocks", Choice.MULTIPLE);
choose.setTicker(new Ticker(tickerString()));
choose.addCommand(backCommand);
choose.setCommandListener(this);
try {
RecordEnumeration re = db.enumerate();
while(re.hasNextElement()) {
String theStock = new String(re.nextRecord());
choose.append(Stock.getName(theStock)+" @ " +
Stock.getPrice(theStock),null);
}
} catch(Exception ex) {}
display.setCurrent(choose);
currentMenu = "List";
}
// Handle command events
public void commandAction(Command c, Displayable d) {
String label = c.getLabel();
if (label.equals("Exit")) {
destroyApp(true);
} else if (label.equals("Save")) {
if(currentMenu.equals("Add")) {
// add it to database
try {
String userInput = input.getString();
String pr = getQuote(userInput);
db.addNewStock(pr);
ticker.setString(tickerString());
} catch(IOException e) {
} catch(NumberFormatException se) {
}
mainMenu();
}
} else if (label.equals("Back")) {
if(currentMenu.equals("List")) {
// go back to menu
mainMenu();
} else if(currentMenu.equals("Add")) {
// go back to menu
mainMenu();
}
} else {
List down = (List)display.getCurrent();
switch(down.getSelectedIndex()) {
case 0: listStocks();break;
case 1: addStock();break;
}
}
}
}
class StockDB {
RecordStore recordStore = null;
public StockDB() {}
// Open a record store with the given name
public StockDB(String fileName) {
try {
recordStore = RecordStore.openRecordStore(fileName, true);
} catch(RecordStoreException rse) {
rse.printStackTrace();
}
}
// Close the record store
public void close() throws RecordStoreNotOpenException,RecordStoreException {
if (recordStore.getNumRecords() == 0) {
String fileName = recordStore.getName();
recordStore.closeRecordStore();
recordStore.deleteRecordStore(fileName);
} else {
recordStore.closeRecordStore();
}
}
// Add a new record (stock)
// to the record store
public synchronized void addNewStock(String record) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
DataOutputStream outputStream = new DataOutputStream(baos);
try {
outputStream.writeUTF(record);
} catch (IOException ioe) {
System.out.println(ioe);
ioe.printStackTrace();
}
byte[] b = baos.toByteArray();
try {
recordStore.addRecord(b, 0, b.length);
} catch (RecordStoreException rse) {
System.out.println(rse);
rse.printStackTrace();
}
}
// Enumerate through the records.
public synchronized RecordEnumeration enumerate() throws
RecordStoreNotOpenException {
return recordStore.enumerateRecords(null, null, false);
}
} class Stock {
private static String name, time, price;
// Given a quote from the server,
// retrieve the name,
//price, and date of the stock
public static void parse(String data) {
int index = data.indexOf(""");
name = data.substring(++index,(index = data.indexOf(""", index)));
index +=3;
time = data.substring(index, (index = data.indexOf("-", index))-1);
index +=5;
price = data.substring(index, (index = data.indexOf("<", index)));
}
// Get the name of the stock from
// the record store
public static String getName(String record) {
parse(record);
return(name);
}
// Get the price of the stock from
// the record store
public static String getPrice(String record) {
parse(record);
return(price);
}
}
</source>
<source lang="java">
/*--------------------------------------------------
- SharedTicker.java
- Example from the book: Core J2ME Technology
- Copyright John W. Muchow http://www.CoreJ2ME.ru
- You may use/modify for any non-commercial purpose
- -------------------------------------------------*/
import javax.microedition.midlet.*; import javax.microedition.lcdui.*; public class SharedTicker extends MIDlet implements CommandListener {
private Display display; // Reference to Display object
private List lsProducts; // Main productlist
private Alert alHelp; // Alert to show text and image
private Ticker tkSale; // Ticker of what"s on sale
private Command cmExit; // Command to exit the MIDlet
public SharedTicker()
{
display = Display.getDisplay(this);
cmExit = new Command("Exit", Command.SCREEN, 1);
tkSale = new Ticker("Current Sale: Torchiere Lamp only $29.00");
lsProducts = new List("Products", Choice.IMPLICIT);
lsProducts.append("Floor Lamp", null);
lsProducts.append("Chandelier", null);
lsProducts.append("Help", null);
lsProducts.addCommand(cmExit);
lsProducts.setCommandListener(this);
lsProducts.setTicker(tkSale);
}
public void startApp()
{
display.setCurrent(lsProducts);
}
public void pauseApp()
{
}
public void destroyApp(boolean unconditional)
{
}
public void showAlert()
{
try
{
// Create an image
Image im = Image.createImage("/help.png");
// Create Alert, add text and image, no sound
alHelp = new Alert("Help Information",
"Over 300 unique lighting products!",
im, null);
alHelp.setTimeout(Alert.FOREVER);
alHelp.setTicker(tkSale);
}
catch(Exception e)
{
System.out.println("Unable to read png image.");
}
// Display the Alert. Once dismissed, return to product list
display.setCurrent(alHelp, lsProducts);
}
public void commandAction(Command c, Displayable s)
{
if (c == List.SELECT_COMMAND)
{
switch (lsProducts.getSelectedIndex())
{
case 0:
System.out.println("Floor Lamp selected");
break;
case 1:
System.out.println("Chandelier selected");
break;
case 2:
showAlert();
break;
}
}
else if (c == cmExit)
{
destroyApp(true);
notifyDestroyed();
}
}
}
</source>
Stock Watcher
<source lang="java">
/* License
*
* Copyright 1994-2004 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:
*
* * Redistribution 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 MICROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS 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 THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
import javax.microedition.midlet.*; import javax.microedition.lcdui.*; import java.util.*; public class StockWatcher extends MIDlet {
Display display;
Ticker ticker = new Ticker( "" );
Command exitCommand = new Command(
"Exit", Command.EXIT, 1 );
Timer timer = new Timer();
StockChecker checker = new StockChecker();
TickerForm form = new TickerForm();
Alert alert = new Alert( "Stock Alert!" );
public StockWatcher() {
display = Display.getDisplay( this );
alert.setTimeout( Alert.FOREVER );
}
protected void destroyApp( boolean unconditional ) { }
protected void startApp() {
display.setCurrent( form );
timer.schedule( checker, 0, 30000 );
}
protected void pauseApp() { }
public void exit(){
timer.cancel();
destroyApp( true );
notifyDestroyed();
}
// Display a simple form to hold the ticker
class TickerForm extends Form implements CommandListener {
public TickerForm(){
super( "Stock Watch" );
setTicker( ticker );
addCommand( exitCommand );
setCommandListener( this );
}
public void commandAction( Command c, Displayable d ){
exit();
}
}
// Check the stock values and put up an alert if
// they"re beyond certain limits....
class StockChecker extends TimerTask {
Random generator = new Random();
int sybsValue = 20000;
int sunwValue = 30000;
int ibmValue = 40000;
StringBuffer buf = new StringBuffer();
public void run(){
String values = getStockValues();
ticker.setString( values );
if( sybsValue < 18000 || sybsValue > 22000 ||
sunwValue < 28000 || sunwValue > 32000 ||
ibmValue < 38000 || ibmValue > 42000 ){
alert.setString( values );
}
if( !alert.isShown() ){
display.setCurrent( alert, form );
}
}
private String getStockValues(){
sybsValue = randomStockValue( sybsValue );
sunwValue = randomStockValue( sunwValue );
ibmValue = randomStockValue( ibmValue );
buf.setLength( 0 );
appendValue( "SYBS", sybsValue );
appendValue( "SUNW", sunwValue );
appendValue( "IBM", ibmValue );
return buf.toString();
}
// Generate a random stock value... in the
// real world you"d use HTTP to obtain the
// stock value from a broker"s website.
private int randomStockValue( int oldVal ){
int incr1 = ( generator.nextInt() % 2 );
int incr2 = ( generator.nextInt() % 16 );
if( incr1 < 1 ){
oldVal -= incr1 * 1000;
} else {
oldVal += ( incr1 - 2 ) * 1000;
}
if( incr2 < 8 ){
oldVal -= incr2 * 250;
} else {
oldVal += incr2 * 250;
}
return oldVal;
}
private void appendValue( String stock, int val ){
buf.append( stock );
buf.append( " " );
buf.append( Integer.toString( val / 1000 ) );
buf.append( "." );
buf.append( Integer.toString( val % 1000 ) );
buf.append( " " );
}
}
}
</source>
TickerList
<source lang="java">
/* J2ME: The Complete Reference James Keogh Publisher: McGraw-Hill ISBN 0072227109
- /
//jad file (please verify the jar size) /* MIDlet-Name: TickerList MIDlet-Version: 1.0 MIDlet-Vendor: MyCompany MIDlet-Jar-URL: TickerList.jar MIDlet-1: TickerList, , TickerList MicroEdition-Configuration: CLDC-1.0 MicroEdition-Profile: MIDP-1.0 MIDlet-JAR-SIZE: 100
- /
import javax.microedition.midlet.*; import javax.microedition.lcdui.*; public class TickerList extends MIDlet implements CommandListener {
private Display display;
private List list;
private final String tech;
private final String entertain;
private Ticker ticker;
private Command exit;
private Command submit;
public TickerList()
{
display = Display.getDisplay(this);
tech = new String ("IBM 55 MSFT 32 SUN 52 CISCO 87");
entertain = new String ("CBS 75 ABC 455 NBC 243 GE 21");
exit = new Command("Exit", Command.SCREEN, 1);
submit = new Command("Submit", Command.SCREEN, 1);
ticker = new Ticker(tech);
list = new List("Stock Ticker", Choice.EXCLUSIVE);
list.append("Technology", null);
list.append("Entertainment", null);
list.addCommand(exit);
list.addCommand(submit);
list.setCommandListener(this);
list.setTicker(ticker);
}
public void startApp()
{
display.setCurrent(list);
}
public void pauseApp()
{
}
public void destroyApp(boolean unconditional)
{
}
public void commandAction(Command command, Displayable display)
{
if (command == exit)
{
destroyApp(true);
notifyDestroyed();
}
else if (command == submit)
{
if (list.getSelectedIndex() == 0)
{
ticker.setString (tech);
}
else
{
ticker.setString(entertain);
}
}
}
}
</source>
