alert window until method finishes execution jswings

alert window until method finishes execution jswings

i have added the image in comments The shown image is my window made using
swings.. how do i create an alert window when i click submit button. and
the alert should display until the action performed is
completed(alert+code should run in background).. here is my code
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
//alert window should start here when button performed
//and end based on the output i get
DefaultHttpClient httpclient = new DefaultHttpClient();
jLabel3.setText("");
try {
httpclient.getCredentialsProvider().setCredentials(
new AuthScope(getHost(), AuthScope.ANY_PORT),
new UsernamePasswordCredentials(getUser(), getPass()));
HttpResponse response = null;
HttpEntity entity = null;
try {
response = httpclient.execute(httpget);
if(response.getStatusLine().getStatusCode()==500){
jLabel3.setText("Such Goods Movement does not exist / You
do not have permssions for the entered.");
//end here or
}else if(response.getStatusLine().getStatusCode()==401){
System.out.println(response);
jLabel3.setText("Auth Failed");
//end here or soon based on the event
}
entity = response.getEntity();
System.out.println(entity);
if (entity != null){
InputStream instream = entity.getContent();
System.out.println(instream);
BufferedReader reader = new BufferedReader(
new InputStreamReader(instream));
String inputLine;
String xmlText="";
while ((inputLine = reader.readLine()) != null)
xmlText = xmlText+inputLine+"\n";
System.out.println(xmlText);
try {
DocumentBuilder db =
DocumentBuilderFactory.newInstance().newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xmlText));
DefaultTableModel model = (DefaultTableModel)
jTable1.getModel();
model.setRowCount(0);
Document doc = db.parse(is);
NodeList nodes =
doc.getElementsByTagName("MaterialMgmtInternalMovementLine");
for (int i = 0; i < nodes.getLength(); i++) {
Element element = (Element) nodes.item(i);
getListGRNLine(element);
}
} catch (SAXException ex) {
Logger.getLogger(GoodsReceipt.class.getName()).log(Level.SEVERE,
null, ex);
} catch (ParserConfigurationException ex) {
Logger.getLogger(GoodsReceipt.class.getName()).log(Level.SEVERE,
null, ex);
}
}
} catch(UnknownHostException e){
jLabel3.setText("URL Not Found / Check Internet Connectivity");
} catch(NoRouteToHostException f){
jLabel3.setText("URL Not Found / Check Internet Connectivity");
}
catch (IOException ex) {
Logger.getLogger(GoodsReceipt.class.getName()).log(Level.SEVERE,
null, ex);
}
try {
EntityUtils.consume(entity);
} catch (IOException ex) {
Logger.getLogger(GoodsReceipt.class.getName()).log(Level.SEVERE,
null, ex);
}
} catch (UnsupportedEncodingException ex) {
Logger.getLogger(GoodsReceipt.class.getName()).log(Level.SEVERE,
null, ex);
} finally {
// When HttpClient instance is no longer needed,
// shut down the connection manager to ensure
// immediate deallocation of all system resources
httpclient.getConnectionManager().shutdown();
}
please help me how to do this