Stock Watcher
/* 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( ' ' );
}
}
}
Related examples in the same category
