import javax.microedition.midlet.MIDlet;
import javax.microedition.rms.RecordStore;

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

    public ReadWrite() {
        // Create the record store
        openRecStore(); 
        
        // Write a few records and read them back
        writeRecord( "JGuru" );
        writeRecord( "MIDP" );
        readRecords();
        closeRecStore(); 
        deleteRecStore();
    }

    public void destroyApp( boolean unconditional ) {
    }

    public void startApp() {
        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( HD_STORE, true );
        } catch( Exception e ) {
            writeOutput( e.toString() );
        }
    }

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

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

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

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

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