My speech at the first Java mobile developer forum event about the kommons project.

1. Kommons: reusable objects for j2me
Antonio Terreno
Mobile Development
Fluidtime DataServices GmbH
info@java2me.org
http://kommons.java2me.org/

2. Long-term Goal
To have a collection of J2ME classes
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Stable
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Easy to use, to integrate
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Tested (j2meunit)
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Open
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Well coded
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3. Kommons logging
Logger “like” log4j
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Appenders
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Console
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Bluetooth
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Http
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Debugging levels
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Enabled/Disabled
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Debug level
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Info level
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Easy to use
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Perfect integration with Log4E
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4. Kommons logging
private final static Logger logger =
Logger.getLogger(quot;LoggerExampleMIDletquot;);
protected void startApp() {
logger.addAppender(AppenderType.CONSOLE);
logger.addAppender(AppenderType.PHONE);
logger.setDebugEnabled(true);
if (logger.isDebugEnabled()) {
logger.debug(quot;startApp() - startquot;);
}
initDisplay();

5. Midp Worker
Before/After pattern simple implementation
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public abstract class MIDPWorker extends TimerTask
public final void run() {
before();
try {
doWork();
} catch (LogicalException e) {
doCatch(e);
} finally {
after();

6. ISO helpers
IsoDate Helper
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IsoDate parser for ISO 8601 format
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http://www.w3.org/TR/xmlschema-2/#date
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IsoDuration Helper
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IsoDuration parser for ISO 8601 format.
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http://www.w3.org/TR/xmlschema-2/#duration
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IsoDuration format is (-)PnYnMnDTnHnMnS
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7. ISO helpers
IsoDate Helper
●
IsoDate parser for ISO 8601 format
–
http://www.w3.org/TR/xmlschema-2/#date
–
–
IsoDuration Helper
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IsoDuration parser for ISO 8601 format.
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http://www.w3.org/TR/xmlschema-2/#duration
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IsoDuration format is (-)PnYnMnDTnHnMnS
–

8. I/O
Bluetooth
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A simple send & receive client
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Needs your help! :-)
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Integration with BtFree??? Federico Paparoni???
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HTTP
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A complete http client (post/get)
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URL encoding
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Cookie auth supported
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Easy parameters use
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9. Http example
try {
String xml = XMLAdapter.getInstance().toXML(msg);
logger.debug(quot;Postingquot;, xml);
xml = HttpClient.URLencode(xml);
HttpClient httpClient = new HttpClient();
String[][] params = {
{ quot;sXmlMobileRequestquot;, xml },
{ quot;userNamequot;, UserPropertiesWrapper.currentUser() },
};
String response = httpClient.post(Fluidtime.ENDPOINT +
quot;TimeWindow/update.actionquot;, params);
msg = (Message) XMLAdapter.getInstance().fromXML(response);
} catch (LogicalException e) {
logger.debug(e);

10. The cache
A persistence cache for MIDP 2.0
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save(PersistentObject e)
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delete(PersistentObject e)
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PersistentObject find(String id)
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reset()
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boolean isEmpty()
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11. RMS-xml cache
Runtime cache:
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An hash table containing objects
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Shutting down?
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Storing objects in xml format
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Starting up?
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Retrive of the objects from the rms
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12. Problems
How to retrive the objects in cache?
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EntityRecordMapping idea
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It contains the reference from an Entity id and
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Its Record Store Id
How to find an object?
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1. in the runtime cache
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2. in the rms
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3. if found it will be putted on the cache & used
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13. RMS-xml cache
Model
Cache
E.R.
RMS
mapping

14. Benefits
Possibility to store any kind of object
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Possibility to store collection of objects
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15. Next Steps of Action
Involve developers
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Merge other interesting project into
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Javadoc
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Website
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Licence
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Junit testing
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Receive feedbacks
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...
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16. Credits to
Alberto Lagna (CTO Fluidtime GmbH)
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Jean-Marie Dautelle (Javolution.org)
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Fluidtime GmbH
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Java2me.org forum :-)
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Jmdf of course!
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17. Q&A
Questions? Suggestions?
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