如何使用j2me在手机中保存数据？

import javax.microedition.rms.RecordStore;
import javax.microedition.rms.RecordStoreException;
import javax.microedition.rms.RecordStoreNotOpenException;

private RecordStore recordStore;

public void createRecordStore() {
    try {
        recordStore = RecordStore.openRecordStore("MyRecordStore", true);
    } catch (RecordStoreException e) {
        e.printStackTrace();
    }
}

public void addData(String data) {
    try {
        byte[] dataBytes = data.getBytes();
        recordStore.addRecord(dataBytes, 0, dataBytes.length);
    } catch (RecordStoreException e) {
        e.printStackTrace();
    }
}

public String getData(int recordId) {
    String data = "";
    try {
        byte[] dataBytes = recordStore.getRecord(recordId);
        data = new String(dataBytes);
    } catch (RecordStoreException e) {
        e.printStackTrace();
    }
    return data;
}

public void closeRecordStore() {
    try {
        recordStore.closeRecordStore();
    } catch (RecordStoreNotOpenException e) {
        e.printStackTrace();
    } catch (RecordStoreException e) {
        e.printStackTrace();
    }
}