RecordStore: getNumRecords() throws RecordStoreNotOpenException : RecordStore « javax.microedition.rms « Java by API

1. Java by API
2. javax.microedition.rms
3. RecordStore

RecordStore: getNumRecords() throws RecordStoreNotOpenException

 

import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.midlet.MIDlet;
import javax.microedition.rms.RecordStore;

public class J2MEWriteReadExample extends MIDlet implements CommandListener {
  private Display display;

  private Alert alert;

  private Form form = new Form("Record");

  private Command exit = new Command("Exit", Command.SCREEN, 1);

  private Command start = new Command("Start", Command.SCREEN, 1);

  private RecordStore recordstore = null;

  public J2MEWriteReadExample() {
    display = Display.getDisplay(this);
    form.addCommand(exit);
    form.addCommand(start);
    form.setCommandListener(this);
  }

  public void startApp() {
    display.setCurrent(form);
  }

  public void pauseApp() {
  }

  public void destroyApp(boolean unconditional) {
  }

  public void commandAction(Command command, Displayable displayable) {
    if (command == exit) {
      destroyApp(true);
      notifyDestroyed();
    } else if (command == start) {
      try {
        recordstore = RecordStore.openRecordStore("myRecordStore", true);
        String outputData = "First Record";
        byte[] byteOutputData = outputData.getBytes();
        recordstore.addRecord(byteOutputData, 0, byteOutputData.length);

        byte[] byteInputData = new byte[1];
        int length = 0;
        for (int x = 1; x <= recordstore.getNumRecords(); x++) {
          if (recordstore.getRecordSize(x) > byteInputData.length) {
            byteInputData = new byte[recordstore.getRecordSize(x)];
          }
          length = recordstore.getRecord(x, byteInputData, 0);
        }
        alert = new Alert("Reading", new String(byteInputData, 0, length), null, AlertType.WARNING);
        alert.setTimeout(Alert.FOREVER);
        display.setCurrent(alert);

        recordstore.closeRecordStore();
        if (RecordStore.listRecordStores() != null) {
          RecordStore.deleteRecordStore("myRecordStore");
        }
      } catch (Exception error) {
        alert = new Alert("Error Removing", error.toString(), null, AlertType.WARNING);
        alert.setTimeout(Alert.FOREVER);
        display.setCurrent(alert);
      }
    }
  }
}

   
  

Related examples in the same category