jar file directly opening and not installing mobile

Question

I am trying to create a java me application . The code is hello xxxx, its simple.

But the problem is that when I port it to a nokia series 40 phone or an emulator, the .jad or .jar file opens directly, but in other series 60 phones like e72 or e63 it installs.

public class Hellostackoverflow extends MIDlet{
  private Form form;
  private Display display;

  public Hellostackoverflow(){
  super();
  }

  public void startApp(){
  form = new Form("Hello stackoverflow");
  String msg = "I love stackoverflow";
  form.append(msg);
  display = Display.getDisplay(this);
  display.setCurrent(form);
  }

  public void pauseApp(){}

  public void destroyApp(boolean unconditional){
  notifyDestroyed();
  }
}

But I want to install it in phone(and emulator). How can I install it? PS: The problem is in code I think. Normally all apps get installed in emulator or phone. This is not phone problem but some error is in my java file..I think.

Answer 1

Its depend on the phone's environment ( operating system ) whether to direct run Java ME application or run it after the installation.

S40 Series doesn't have Symbian Operating system so they are directly opening .JAR files, even you can view .JAD file in S40 Series phones.

On the other hand in S60 Series phones, they have Symbian Operating system and they allow to execute Java ME application only after the installation.