Showing posts with label J2ME. Show all posts
Showing posts with label J2ME. Show all posts

Friday, July 16, 2010

J2ME - Read and write using RMS

Links to this post
This is sample application to read and write record using RMS in J2ME mobie application


import javax.microedition.rms.*;

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

public class ReadWrite extends MIDlet
{
private RecordStore rs = null;
static final String REC_STORE = "db_1";

public ReadWrite()
{
openRecStore(); // Create the record store

// Write a few records and read them back
writeRecord("J2ME and MIDP");
writeRecord("Wireless Technology");
readRecords();

closeRecStore(); // Close record store
deleteRecStore(); // Remove the record store
}

public void destroyApp( boolean unconditional )
{
}

public void startApp()
{
// There is no user interface, go ahead and shutdown
destroyApp(false);
notifyDestroyed();
}

public void pauseApp()
{
}

public void openRecStore()
{
try
{
// The second parameter indicates that the record store
// should be created if it does not exist
rs = RecordStore.openRecordStore(REC_STORE, true );
}
catch (Exception e)
{
db(e.toString());
}
}

public void closeRecStore()
{
try
{
rs.closeRecordStore();
}
catch (Exception e)
{
db(e.toString());
}
}

public void deleteRecStore()
{
if (RecordStore.listRecordStores() != null)
{
try
{
RecordStore.deleteRecordStore(REC_STORE);
}
catch (Exception e)
{
db(e.toString());
}
}
}

public void writeRecord(String str)
{
byte[] rec = str.getBytes();

try
{
rs.addRecord(rec, 0, rec.length);
}
catch (Exception e)
{
db(e.toString());
}
}

public void readRecords()
{
try
{
// Intentionally make this too small to test code below
byte[] recData = new byte[5];
int len;

for (int i = 1; i <= rs.getNumRecords(); i++) { if (rs.getRecordSize(i) > recData.length)
recData = new byte[rs.getRecordSize(i)];

len = rs.getRecord(i, recData, 0);
System.out.println("Record #" + i + ": " + new String(recData, 0, len));
System.out.println("------------------------------");
}
}
catch (Exception e)
{
db(e.toString());
}
}

private void db(String str)
{
System.err.println("Msg: " + str);
}
}

Author : Anuj Patel

Blog : http://goldenpackagebyanuj.blogspot.in/

Thursday, March 19, 2009

How to install a J2ME aplication on a mobile device

Links to this post
There are lots of ways to install MIDlets on a mobile phone. You can use the InfraRed, Bluetooth, Serial or OTA to install jar/jad files.

Serial, Infrared and Bluetooth

To download jad/jar files from PC and transfer to your device can be done via serial cable or infra-red link or bluetooth.

OTA Provisioning

The term Application Management Software (AMS) is generally used to describe the software components that take on the responsibility of locating MIDlet suites, how MIDlet suites will be installed on a cell phone or a PDA, and what facilities are to be provided to allow the user to select and launch an installed MIDlet or to remove MIDlet suites from the device.

With OTA provisioning, MIDlet suites are placed on web servers and provided a hypertext links to them. A user activates the links to download the MIDlets to a cell phone via a WAP or Internet microbrowser.