'lazy' download test

Question

http://www.javasaver.com/testjs/jws/cache/
Here is one test of the JWS download behaviour
for jar and resources marked as lazy.
Does it work for you?
(It should appear on-screen real quick, once
you click a list item, the image download is
initiated and the GUI ..locks until the image
is on-screen)
This raises some questions though.
1) On my box, the lazy downloads got no progress
dialog - is that expected behaviour? Is there any
easy (configuration) way to put it back?
2) I had to reference the classes in the lazily
downloaded jars using reflection. Are
there easier ways to reference the lazy resources
without invoking an eager download?
Note that I have also linked to a file containing
the source, media and build file, to make it easy
to download and experiment with off the local
file system.
All results, comments welcome.

Answer 1

http://www.javasaver.com/testjs/jws/cache/#eg5
Is the best example so far. The previous examples
blocked the EDT, and that caused the 'blank' dialogs
that were observed.
I am having new problems with it though,
& would appreciate any ideas..
The issue is that the second invocation
of the download service fails.
Here is some output from the web start console.
Part animal cached!
jar:http://www.javasaver.com/testjs/jws/cache5/animalmedia.jar!/image/DCP_7940.jpg
DownloadServiceListener com.sun.jnlp.DownloadServiceImpl$DefaultProgressImpl@2f1921
Part plant downloading!
jar:http://www.javasaver.com/testjs/jws/cache5/plantmedia.jar!/image/100_1829-800x600.jpg
DownloadServiceListener com.sun.jnlp.DownloadServiceImpl$DefaultProgressImpl@2f1921
Part art downloading!
java.lang.RuntimeException: canceled by user
     at com.sun.jnlp.DownloadServiceImpl$DefaultProgressImpl.progress(Unknown Source)
     at com.sun.jnlp.DownloadServiceImpl$ProgressHelper.<init>(Unknown Source)
     at com.sun.jnlp.DownloadServiceImpl$6.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at com.sun.jnlp.DownloadServiceImpl.loadPart(Unknown Source)
     at com.sun.jnlp.DownloadServiceImpl.loadPart(Unknown Source)
     at test.JWSCacheTest.run(JWSCacheTest.java:78)
     at java.lang.Thread.run(Unknown Source)
jar:http://www.javasaver.com/testjs/jws/cache5/artmedia.jar!/image/scan0036-670x470.jpgWhile this is the code for the run() method,
Line 78 has a comment added..
It is the call to ..
downloadservice.loadPart(Sring, String)
..that is throwing the Exceptionpublic void run() {
  String title = getTitle();
  setTitle("Loading " + resourceName);
  try {
    if (downloadservice==null) {
      downloadservice = (DownloadService)ServiceManager.
        lookup("javax.jnlp.DownloadService");
    if ( !downloadservice.isPartCached(part) ) {
      DownloadServiceListener dsl =
        downloadservice.getDefaultProgressWindow();
      System.out.println("DownloadServiceListener " + dsl);
      System.out.println("Part " + part + " downloading!");
      downloadservice.loadPart(part, dsl);  // code line 78
    } else {
      System.out.println("Part " + part + " cached!");
  } catch(Exception e) {
    // ignore the USE or IOE and proceed..
    e.printStackTrace();
  try {
    Class displayClass = Class.forName(resourceName);
    setTitle(title);
    imagePanel.add(
      (Component)displayClass.newInstance(),
      images[index]);
    cl.show(imagePanel, images[index]);
  } catch(Exception e) {
    setTitle(title);
    imagePanel.add(
      new JLabel("Error loading!"),
      images[index]);
  validate();
}Why would that be showing as 'canceled by user'
on any second invocation of the downloadservice?
Is there something I am forgetting to reset at
the end of the first invocation?