Database in J2ME - java-me

Question

I am new in J2ME.
In my Application, I want to add the Multiple Records in the Record Store and also want to access it.
How can I add the multiple Records in the Record Store and how can I access it?

Answer 1

Here is my library code for RMS, just study it, it is very easy to implement, all the methods like insert,updated, delete is there.
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordStore;
import javax.microedition.rms.RecordStoreFullException;
import javax.microedition.rms.RecordStoreNotOpenException;
import com.project.gui.components.CustomAlert;
import com.project.gui.midlet.MyMidlet;
public class RMSStore
{
private RecordStore rs = null;
public void openRecordStore(String str)
{
try
{
if(rs == null)
{
rs = RecordStore.openRecordStore(str, true);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void closeRecordStore()
{
try
{
if(rs!=null)
{
rs.closeRecordStore();
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void deleteRecordStore(String storenName)
{
try
{
RecordStore.deleteRecordStore(storenName);
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void deleteRMS(String storenName)
{
int count = 0;
try
{
RecordStore newRS = RecordStore.openRecordStore(storenName, true);
count = newRS.getNumRecords();
newRS.closeRecordStore();
}
catch ( Exception e )
{
System.out.println ( "Error while Opening " + e.toString() );
}
if ( count > 0 )
{
try
{
RecordStore.deleteRecordStore(storenName);
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
public static String[] listAllRecordStore ()
{
return RecordStore.listRecordStores();
}
public boolean SearchRecord(String Rec)
{
String [] data = getRecordData();
for ( int i = 0 ; i < data.length ; i++ )
{
if ( Rec.toString().trim().equals(data[i].toString().trim()) )
{
data = null; // System.gc();
return true;
}
}
data = null; // System.gc();
return false;
}
public boolean SearchRecord(String Rec, int pos )
{
String [] data = getRecordData();
Rec = Rec.substring(0,pos);
for ( int i = 0 ; i < data.length ; i++ )
{
data[i] = data[i].substring(0, pos );
if ( Rec.toString().trim().equals(data[i].toString().trim()) )
{
data = null; // System.gc();
return true;
}
}
data = null; // System.gc();
return false;
}
public int getCurrentRecordID ( RMSStore rmsTable, String Rec )
{
RecordEnumeration re = null;
try
{
re = rmsTable.getRecordEnumData();
while ( re.hasNextElement() )
{
int id = re.nextRecordId();
String record = rmsTable.getRecordFromId(id);
if ( record.indexOf(Rec) != -1 )
{
return id;
}
}
}
catch ( Exception e ) { System.out.println ( "getCurrentRecordID Error:" + e.toString() ); }
return -1;
}
public int writeRecord(String str)
{
int id = 0;
try
{
id = rs.addRecord(str.getBytes(), 0, str.getBytes().length);
}
catch (RecordStoreFullException e)
{
CustomAlert memoryFullAlert = new CustomAlert("");
memoryFullAlert.setString("Memory Full");
MyMidlet.getDisplay().setCurrent(memoryFullAlert);
}
catch (Exception e)
{
e.printStackTrace();
}
return id;
}
public int writeByteRecord(byte[] data)
{
int id = -1;
try
{
id = rs.addRecord(data, 0, data.length);
}
catch (RecordStoreFullException e)
{
e.printStackTrace();
CustomAlert memoryFullAlert = new CustomAlert("");
memoryFullAlert.setString("Memory Full");
MyMidlet.getDisplay().setCurrent(memoryFullAlert);
}
catch (Exception e)
{
e.printStackTrace();
}
return id;
}
public int getRecordCount()
{
try
{
return rs.getNumRecords();
}
catch (Exception e)
{
e.printStackTrace();
}
return 0;
}
public byte[] getRecordDataFromId(int id)
{
byte[] data = null;
try
{
data = rs.getRecord(id);
}
catch (Exception e)
{
e.printStackTrace();
}
return data;
}
public String getRecordFromId(int id)
{
return new String(getRecordDataFromId(id));
}
public byte[] getRecordByteFromId(int id)
{
return getRecordDataFromId(id);
}
public void deleteRecord(int id)
{
try
{
rs.deleteRecord(id);
}
catch (Exception e)
{
e.printStackTrace();
}
}
public boolean checkRecordExists(String compare)
{
for(int i = 0; i < getRecordCount(); i++)
{
if(compare.equals(getRecordFromId(i + 1)))
{
return true;
}
}
return false;
}
public int getMaxRMSSize()
{
int size = 0;
try
{
size = rs.getSizeAvailable() + rs.getSize();
}
catch (RecordStoreNotOpenException e)
{
e.printStackTrace();
}
return size;
}
public void setRecordById(String str, int id)
{
try
{
rs.setRecord(id, str.getBytes(), 0, str.getBytes().length);
}
catch (Exception e)
{
e.printStackTrace();
}
}
public int getNextRecordId()
{
int id = 0;
try
{
id = rs.getNextRecordID();
}
catch (Exception e)
{
e.printStackTrace();
}
return id;
}
public RecordEnumeration getRecordEnumData ()
{
try
{
return rs.enumerateRecords(null, null, false);
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
public String [] getRecordData()
{
String[] str = null;
int counter = 0;
try
{
RecordEnumeration enumeration = rs.enumerateRecords(null, null, false);
str = new String[rs.getNumRecords()];
while(enumeration.hasNextElement())
{
try
{
str[counter] = (new String(enumeration.nextRecord()));
counter ++;
}
catch (Exception e)
{
e.printStackTrace();
}
}
} catch (Exception e) {
e.printStackTrace();
}
return str;
}
}

Answer 2

RMS is a record based data storage mechanism, so you can store multiple records very easily, see following blog to see how RMS works.
http://www.ibm.com/developerworks/library/wi-rms/