Does HttpConnection.openInputStream() blocks ANY threads?

Question

I have a MIDP programme that connects via http and get message responses from a server.
I want it show some animations when connecting.
so, I write 2 threads
1: the http connect thread
2: the observer thread, which watches the http connect thread if it is finished, and every 500L miliseconds do a repaint to draw some animation on canvas.
i simulated a server which takes a minute to respose, and found that all threads stops at hc.openInputStream() ,so there 'll be sure NO animations at all.
so ... could anybody help me about this ...? thanks a lot!

Answer 1

public class HttpMessageReader
    extends Thread {
  String message;
  int loadStatus = -1; //0=over -1=not started yet 1=loading 2=error
  String url;
  public HttpMessageReader(String url) {
    this.url = url;
  public void run() {
    loadStatus = 1;
    HttpConnection hc = null;
    try {
      hc = (HttpConnection) Connector.open(url);
      System.out.println("hc");
// all threads stop here
      DataInputStream ds = new DataInputStream(hc.openInputStream());
      System.out.println("ds");
      message = ds.readUTF();
      System.out.println(message);
      loadStatus = 0;
    catch (IOException ex) {
      ex.printStackTrace();
      loadStatus = 2;
    finally {
      try {
        if (hc != null) {
          hc.close();
      catch (IOException ignored) {}
}observer threads run():
  public void run() {
    System.out.println("observer");
while(true){
    try {
      synchronized(this){ // i doubt anything wrong here?
        this.wait(500l);
    catch (InterruptedException ex) {
      ex.printStackTrace();
    progress++;
//..then do repaint();
  }then in the GUI startup ,a new observer.start() and a new HttpMessageReader.start() .