RMS 存储值在 J2ME 仿真器中不是永久可用的
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【中文标题】RMS 存储值在 J2ME 仿真器中不是永久可用的【英文标题】：RMS stored values are not permanently available in J2ME emulator 【发布时间】：2012-05-20 10:50:34 【问题描述】：我有代码在 J2ME 中使用 RMS 存储值。它在模拟器上运行良好。所以，我的第一个问题是
当我重新启动模拟器时，所有存储的值都会被删除。
存储的值显示在模拟器中，但不显示在我正在测试我的应用程序的移动设备中。
我正在使用 NetBeans 开发我的 J2ME 应用程序。
===更新===
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import javax.microedition.rms.*;
public class TryNew extends MIDlet implements CommandListener, ItemCommandListener
private RecordStore record;
private StringItem registered;
static final String REC_STORE = "SORT";
//Button existUser;
Display display = null;
private Ticker ticker;
Form form = null;
Form form1 = null;
TextField tb, tb1, tb2, tb3;
ChoiceGroup operator = null;
String str = null;
Command backCommand = new Command("Back", Command.BACK, 0);
Command loginCommand = new Command("Login", Command.OK, 2);
Command saveCommand = new Command("Save New", Command.OK, 1);
Command sendCommand = new Command("Send", Command.OK, 2);
Command selectCommand = new Command("Select", Command.OK, 0);
Command exitCommand = new Command("Exit", Command.STOP, 3);
private ValidateLogin ValidateLogin;
public TryNew()
public void startApp() throws MIDletStateChangeException
display = Display.getDisplay(this);
form = new Form("Login");
registered = new StringItem("", "Registered ?", StringItem.BUTTON);
form1 = new Form("Home");
tb = new TextField("Login Id: ", "", 10, TextField.PHONENUMBER);//TextField.PHONENUMBER
tb1 = new TextField("Password: ", "", 30, TextField.PASSWORD);
operator = new ChoiceGroup("Select Website", Choice.POPUP, new String[]"Game", "Joke", "SMS", null);
form.append(tb);
form.append(tb1);
form.append(operator);
form.append(registered);
registered.setDefaultCommand(selectCommand);
registered.setItemCommandListener(this);
form.addCommand(saveCommand);
ticker = new Ticker("Welcome Screen");
form.addCommand(loginCommand);
form.addCommand(selectCommand);
form.addCommand(exitCommand);
// existUser = new StringItem(null, "Registered ?");
// form.append(existUser);
form.setCommandListener(this);
form1.addCommand(exitCommand);
form1.addCommand(sendCommand);
form1.setCommandListener(this);
form.setTicker(ticker);
display.setCurrent(form);
public void pauseApp()
public void destroyApp(boolean unconditional)
void showMessage(String message, Displayable displayable)
Alert alert = new Alert("");
alert.setTitle("Error");
alert.setString(message);
alert.setType(AlertType.ERROR);
alert.setTimeout(5000);
display.setCurrent(alert, displayable);
public void commandAction(Command c, Displayable d)
if (c == exitCommand)
destroyApp(true);
notifyDestroyed();
else if (c == backCommand)
display.setCurrent(form);
else if (c == loginCommand)
ValidateLogin = new ValidateLogin(this);
ValidateLogin.start();
ValidateLogin.validateLogin(tb.getString(), tb1.getString(), operator.getString(operator.getSelectedIndex()));
else if (c == saveCommand)
openRecord();
writeRecord(tb.getString(), tb1.getString(), operator.getString(operator.getSelectedIndex()));
closeRecord();
showAlert("Login Credential Saved Successfully !!");
////==============================================================================/////
/// Record Management
public void openRecord()
try
record = RecordStore.openRecordStore(REC_STORE, true);
catch (Exception e)
db(e.toString());
public void closeRecord()
try
record.closeRecordStore();
catch (Exception e)
db(e.toString());
public void deleteRecord()
if (RecordStore.listRecordStores() != null)
try
RecordStore.deleteRecordStore(REC_STORE);
catch (Exception e)
db(e.toString());
public void writeRecord(String login_id, String pwd, String operator_name)
String credential = login_id + "," + pwd + "," + operator_name;
byte[] rec = credential.getBytes();
try
if (login_id.length() > 10 || login_id.length() < 10)
showAlert("Please Enter valid Login Id");
else if (pwd.length() < 1)
showAlert("Please Password !!");
else
record.addRecord(rec, 0, rec.length);
catch (Exception e)
db(e.toString());
private void showAlert(String err)
Alert a = new Alert("");
a.setString(err);
a.setTimeout(Alert.FOREVER);
display.setCurrent(a);
public void readRecord()
try
if (record.getNumRecords() > 0)
Comparator comp = new Comparator();
RecordEnumeration re = record.enumerateRecords(null, comp, false);
while (re.hasNextElement())
String str = new String(re.nextRecord());
showAlert(str);
catch (Exception e)
db(e.toString());
private void db(String error)
System.err.println("Exception: " + error);
public void commandAction(Command c, Item item)
if (c == selectCommand && item == registered)
openRecord();
readRecord();
closeRecord();
class Comparator implements RecordComparator
public int compare(byte[] rec1, byte[] rec2)
String str1 = new String(rec1);
String str2 = new String(rec2);
int result = str1.compareTo(str2);
if (result == 0)
return RecordComparator.EQUIVALENT;
else if (result < 0)
return RecordComparator.PRECEDES;
else
return RecordComparator.FOLLOWS;
class ValidateLogin implements Runnable
TryNew midlet;
private Display display;
String login_id;
String pwd;
String operator_name;
public ValidateLogin(TryNew midlet)
this.midlet = midlet;
display = Display.getDisplay(midlet);
public void start()
Thread t = new Thread(this);
t.start();
public void run()
if (login_id.length() > 10 || login_id.length() < 10)
showAlert("Please Enter valid Login Id");
else if (pwd.length() < 1)
showAlert("Please Password !!");
else
showHome();
/* This method takes input from user like text and pass
to servlet */
public void validateLogin(String login_id, String pwd, String operator_name)
this.login_id = login_id;
this.pwd = pwd;
this.operator_name = operator_name;
/* Display Error On screen*/
private void showAlert(String err)
Alert a = new Alert("");
a.setString(err);
a.setTimeout(Alert.FOREVER);
display.setCurrent(a);
private void showHome()
tb2 = new TextField("To: ", "", 30, TextField.PHONENUMBER);
tb3 = new TextField("Message: ", "", 300, TextField.ANY);
form1.append(tb2);
form1.append(tb3);
form1.addCommand(loginCommand);
//display.setCurrent(tb3);
display.setCurrent(form1);
;
这是我得到的，当我点击Manage Emulator
【问题讨论】：
请上传您的代码。 您是 J2ME/编程新手吗？ 是的，我已经提到过。 请任何人帮助我找到 NetBeans 中的 storage_root 选项，或者在我的手机中存储和检索数据的任何替代方法。 【参考方案1】：您需要在WTK中修复您的应用程序的storage_root，
每当您启动 enulator 时，它都会引用相同的 storage_root，默认情况下它会为每个会话创建不同的数据文件
【讨论】：
我该怎么做，因为我是 J2ME 的新手。提前致谢！！ 我现在没有安装 WTK，右键单击 netbeans 中的项目，然后应该有一些设置叫做管理模拟器检查应该有一个选项 storage_root，你应该看到类似的东西this 我找到了manage Emulator的选项，但是没有找到像storage_root这样的选项
检查图像并尝试找到它
我刚刚上传了截图，点击Manage Emulator以上是关于RMS 存储值在 J2ME 仿真器中不是永久可用的的主要内容，如果未能解决你的问题，请参考以下文章