ProgressMonitorInputStream test

ProgressMonitorInputStream: "..a progress monitor to monitor
the progress of reading the input stream. If it's taking a
while, a ProgressDialog will be popped up to inform the user."

Sounds neat, huh? Wrap a plain old Inputstream in one of
these, and the user is kept informed. But I cannot get
it to work!

The code (below) uses it, and offers two URL's, the first
being the entire class list of the Java 6 API, the second
being the trivially small content of the frames based
index page (it would be large if the JEP was interpreting
the input as HTML, but it is displayed as plain text).

Yet while loading the first URL here, I get:-

Wed Sep 26 22:14:42 ACT 2007 Start load
Wed Sep 26 22:18:54 ACT 2007 End load

Over 4 minutes duration, but no appearance of the progress
dialog!

What does 'a while' mean?
Does this code work (pop a progress dialog) for you?
Assuming 'no' for the previous question.
Are there variants of this code that *do* pop the dialog?

If you have an very fast connection, try setting
the URL to point at something much bigger, the
JComboBox is editable.

Thoughts, comments, bug report URLs and solutions
all welcome.

<sscce>
// this is what we are testing..
import javax.swing.ProgressMonitorInputStream;

import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JEditorPane;
import javax.swing.JScrollPane;
import javax.swing.JComboBox;
import javax.swing.SwingUtilities;

import java.io.IOException;
import java.io.InputStream;

import java.net.URL;
import java.net.MalformedURLException;

import java.util.Date;

class TestStreamProgress extends JFrame {

  JEditorPane output;

  TestStreamProgress() throws MalformedURLException {
    super("ProgressMonitorInputStream - Test");
    output = new JEditorPane();
    output.setText("Choose a resource to load");

    this.getContentPane().add(
      new JScrollPane(output)
      );
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    pack();
    setSize(600,400);
    setLocationRelativeTo(null);
    setVisible(true);

    String[] resourceLocator = {
      "http://java.sun.com/javase/6"+
      "/docs/api/allclasses-frame.html",
      "http://java.sun.com/javase/6/"+
      "docs/api/index.html", // a small resource..
      "other (type URL)"
    };
    JComboBox resourceSelector =
      new JComboBox(resourceLocator);
    resourceSelector.setEditable(true);
    JOptionPane.showMessageDialog(null, resourceSelector);
    String resource =
      (String)resourceSelector.getSelectedItem();
    URL url = new URL( resource );
    loadResource(url);
  }

  public void loadResource(final URL location) {
    output.setText("Loading..");
    Thread t = new Thread() {
      public void run() {
        try {
          final InputStream is = location.openStream();
          ProgressMonitorInputStream pmis =
            new ProgressMonitorInputStream(
              output,
              "Loading..",
              is
              );
          System.out.println( new Date() +
            " \tStart load" );
          output.read( pmis, null );
          System.out.println( new Date() +
            " \tEnd load" );
        } catch(Exception e) {
          e.printStackTrace();
        }
      }
    };
    SwingUtilities.invokeLater(t);
  }

  public static void main(String[] args) {
    Thread t = new Thread() {
      public void run() {
        try {
          TestStreamProgress tsp =
            new TestStreamProgress();
        } catch(MalformedURLException e) {
          e.printStackTrace();
        }
      }
    };
    SwingUtilities.invokeLater(t);
  }
}
</sscce>

--
Andrew Thompson
http://www.athompson.info/andrew/

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