ConnectionThread.java

//=============================StartUp.java===============================

public class StartUp extends UiApplication
{
	public static void main(String[]ali)
	{
		StartUp start=new StartUp();
		start.enterEventDispatcher();
	}
	public StartUp()
	{
		this.pushScreen(new LoadingScreen());
	}

	public static void exceptionHandling(final String exception)
	{
		UiApplication.getUiApplication().invokeLater(new Runnable()
		{
			public void run()
			{
				Dialog.alert(exception);
			}
		});
	}
}

//===================================LoadingScreen.java==============

public class LoadingScreen extends MainScreen implements FieldChangeListener
{
	ButtonField click;
	public LoadingScreen()
	{
	    setTitle("Loading Screen");
	    createGUI();
	}

	private void createGUI()
	{
		click=new ButtonField("click");
		click.setChangeListener(this);
		add(click);
	}

	public void fieldChanged(Field field, int context)
	{
		if(field==click)
		{
			ConnectionThread thread=new ConnectionThread(this,"http://startlogic.totemcat.net/sika/WebServices/sikainfo.php?category=0");
			thread.start();
		}
	}

	public boolean onMenu(int instance)
	{
	    return true;
	}

	public boolean onClose()
	{
		return super.onClose();
	}
}

//==============================ConnectionThread.java=============


public class ConnectionThread extends Thread
{
	LoadingScreen loadingScreen;
	String url;
	HttpConnection httpConnection;
	InputStream inputStream;
	StringBuffer stringBuffer=new StringBuffer();
	public ConnectionThread(LoadingScreen loadingScreen, String url)
	{
		this.loadingScreen=loadingScreen;
		this.url=url;
	}
	public void run()
	{
		try
		{
			httpConnection=(HttpConnection) Connector.open(url+";interface=wifi");
			int response=httpConnection.getResponseCode();
			if(response==HttpConnection.HTTP_OK)
			{
				inputStream=httpConnection.openInputStream();
				int c;
				while((c=inputStream.read())!=-1)
				{
					stringBuffer.append((char)c);
				}
				callBack(stringBuffer.toString());
			}
			else
			{
				callBack("ERROR");
			}
		}
		catch (Exception e)
		{
			synchronized (UiApplication.getEventLock())
			{
				UiApplication.getUiApplication().popScreen(UiApplication.getUiApplication().getActiveScreen());
				StartUp.exceptionHandling(e.getMessage());
			}
		}
		finally
		{
			try
			{
				if(httpConnection!=null)
				{
					httpConnection.close();
				}
				if(inputStream!=null)
				{
					inputStream.close();
				}
			}
			catch (Exception e2)
			{}
		}
	}
	private void callBack(String response)
	{
		if(response.equals("ERROR"))
		{
			UiApplication.getUiApplication().popScreen(UiApplication.getUiApplication().getActiveScreen());
			StartUp.exceptionHandling("URL Not found");
		}
		else
		{
			try
			{
				System.out.println(response);
				//do what you want;
			}
			catch (Exception e)
			{
				StartUp.exceptionHandling("Data Not found");
			}
		}
	}
}