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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.RecordComparator;
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordStore;
public class J2MESortExample extends MIDlet implements CommandListener {
private Display display;
private Alert alert;
private Form form = new Form("Mixed RecordEnumeration", null);
private Command exit = new Command("Exit", Command.SCREEN, 1);
private Command start = new Command("Start", Command.SCREEN, 1);
private RecordStore recordstore = null;
private RecordEnumeration recordEnumeration = null;
private Comparator comparator = null;
public J2MESortExample() {
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[] = { "M", "B", "A" };
for (int x = 0; x < 3; x++) {
byte[] byteOutputData = outputData[x].getBytes();
recordstore.addRecord(byteOutputData, 0, byteOutputData.length);
}
StringBuffer buffer = new StringBuffer();
Comparator comparator = new Comparator();
recordEnumeration = recordstore.enumerateRecords(null, comparator, false);
while (recordEnumeration.hasNextElement()) {
buffer.append(new String(recordEnumeration.nextRecord()));
buffer.append("\n");
}
alert = new Alert("Reading", buffer.toString(), null, AlertType.WARNING);
alert.setTimeout(Alert.FOREVER);
display.setCurrent(alert);
recordstore.closeRecordStore();
if (RecordStore.listRecordStores() != null) {
RecordStore.deleteRecordStore("myRecordStore");
recordEnumeration.destroy();
}
} catch (Exception error) {
alert = new Alert("Error Removing", error.toString(), null, AlertType.WARNING);
alert.setTimeout(Alert.FOREVER);
display.setCurrent(alert);
}
}
}
}
class Comparator implements RecordComparator {
public int compare(byte[] record1, byte[] record2) {
String string1 = new String(record1), string2 = new String(record2);
int comparison = string1.compareTo(string2);
if (comparison == 0)
return RecordComparator.EQUIVALENT;
else if (comparison < 0)
return RecordComparator.PRECEDES;
else
return RecordComparator.FOLLOWS;
}
}
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