eclipse 中用javame为什么不能在同一个包中调用另外一个类？

(这是在做老师要求交的一个大作业中遇到的)在Main类中调用同一个包中的Login类,出错提示如下，百度过好像是API的什么安全问题，但弄不懂，请各位大神帮帮忙  %>_<%
 提示错误：
Running with locale: Chinese (Simplified)_People's Republic of China.936
java.lang.SecurityException: Application not authorized to access the restricted API
at com.sun.midp.security.SecurityToken.checkIfPermissionAllowed(+40)
at com.sun.midp.security.SecurityToken.checkIfPermissionAllowed(+7)
at com.sun.midp.midletsuite.MIDletSuiteImpl.checkIfPermissionAllowed(+8)
at com.sun.midp.midlet.MIDletState.<init>(+83)
at javax.microedition.midlet.MIDletProxy.<init>(+5)
at javax.microedition.midlet.MIDlet.<init>(+13)
at Login.<init>(+4)
at Main.commandAction(+15)
at javax.microedition.lcdui.Display$DisplayAccessor.commandAction(+282)
at javax.microedition.lcdui.Display$DisplayManagerImpl.commandAction(+10)
at com.sun.midp.lcdui.DefaultEventHandler.commandEvent(+68)
at com.sun.midp.lcdui.AutomatedEventHandler.commandEvent(+47)
at com.sun.midp.lcdui.DefaultEventHandler$QueuedEventHandler.handleVmEvent(+194)
at com.sun.midp.lcdui.DefaultEventHandler$QueuedEventHandler.run(+51)
main类中的代码：import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class Main extends MIDlet implements CommandListener {
    private Display display;
    private TextBox textBox;
    private Command loginCommand;
    private Command orderCommand;
    private Command submitCommand;
    private Command saveCommand;
    private Command undoCommand;
    private Command exitCommand;
    private Command backCommand;
    
        public Main() {
        display = Display.getDisplay(this);
        textBox = new TextBox("手机点餐系统 V1.0","欢迎使用手机点餐系统，很高兴能为您服务！",50,0);        loginCommand = new Command("登陆",Command.SCREEN,1);
        orderCommand = new Command("点餐",Command.SCREEN,1);
        submitCommand = new Command("提交订单",Command.SCREEN,1);
        saveCommand = new Command("订单状态查询",Command.SCREEN,1);
        undoCommand = new Command("撤销订单",Command.SCREEN,1);
        exitCommand = new Command("退出",Command.SCREEN,1);
        backCommand = new Command("返回",Command.BACK,2);
        
        textBox.addCommand(loginCommand);
        textBox.addCommand(orderCommand);
        textBox.addCommand(submitCommand);
        textBox.addCommand(saveCommand);
        textBox.addCommand(undoCommand);
        textBox.addCommand(exitCommand);
        textBox.addCommand(backCommand);
    }    public void startApp() {
        textBox.setCommandListener(this);
        display.setCurrent(textBox);
    }    public void pauseApp() {
    }    public void destroyApp(boolean uncondition) {
    }    public void commandAction(Command c, Displayable s) {
        if(c == loginCommand) {
         Login login= new Login();
          
         login.startApp();
            textBox.setString("登陆命令被执行");
        }
        if(c == orderCommand) {
            textBox.setString("点餐命令被执行");
        }
        if(c == submitCommand) {
            textBox.setString("提交命令被执行");
        }
        if(c == saveCommand) {
            textBox.setString("查询命令被执行");
        }
        if(c == undoCommand) {
            textBox.setString("撤销命令被执行");
        }
        if(c == backCommand) {
        
          //  textBox.setString("返回命令被执行");
        }
        if(c == exitCommand) {
            textBox.setString("退出命令被执行");
            destroyApp(false);
            notifyDestroyed();
        }
    
       
     }
    
}