FULL PRODUCT VERSION :
1.4.2

ADDITIONAL OS VERSION INFORMATION :
Not Available. Windows XP

EXTRA RELEVANT SYSTEM CONFIGURATION :
Firefox 1.0.6

A DESCRIPTION OF THE PROBLEM :
This is a trace received from a customer running Firefox 1.0.6 on a Windows XP machine.

As the trace indicates, the plugin is trying to load the Applet but crashes with a NPE. It is quite possible that the customer has a configuration error on the server side. However, if that is the case, a clearer error message would be helpfull:

java.lang.NullPointerException

            at sun.plugin.net.proxy.PluginProxyManager.getProxyInfo(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.connectSetup(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.connect(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.getInputStream(Unknown Source)

            at sun.plugin.net.protocol.http.HttpUtils.followRedirects(Unknown Source)

            at sun.plugin.cache.CachedJarLoader.download(Unknown Source)

            at sun.plugin.cache.CachedJarLoader.load(Unknown Source)

            at sun.plugin.cache.JarCache.get(Unknown Source)

            at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)

            at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)

            at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:580)

            at sun.misc.URLClassPath$JarLoader.<init>(URLClassPath.java:543)

            at sun.misc.URLClassPath$3.run(URLClassPath.java:321)

            at java.security.AccessController.doPrivileged(Native Method)

            at sun.misc.URLClassPath.getLoader(URLClassPath.java:310)

            at sun.misc.URLClassPath.getLoader(URLClassPath.java:287)

            at sun.misc.URLClassPath.getResource(URLClassPath.java:157)

            at java.net.URLClassLoader$1.run(URLClassLoader.java:192)

            at java.security.AccessController.doPrivileged(Native Method)

            at java.net.URLClassLoader.findClass(URLClassLoader.java:188)

            at sun.applet.AppletClassLoader.findClass(AppletClassLoader.java:146)

            at java.lang.ClassLoader.loadClass(ClassLoader.java:306)

            at sun.applet.AppletClassLoader.loadClass(AppletClassLoader.java:118)

            at java.lang.ClassLoader.loadClass(ClassLoader.java:251)

            at sun.applet.AppletClassLoader.loadCode(AppletClassLoader.java:577)

            at sun.applet.AppletPanel.createApplet(AppletPanel.java:710)

            at sun.plugin.AppletViewer.createApplet(Unknown Source)

            at sun.applet.AppletPanel.runLoader(AppletPanel.java:639)

            at sun.applet.AppletPanel.run(AppletPanel.java:319)

            at java.lang.Thread.run(Thread.java:595)



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
We cannot reproduce the problem here. There is nothing we can do in our Applet to work out where the problem is as it has not been loaded! As we do not have the source code of the incriminated classes, we cannot see what value is null. If we had, we could probably work out what is wrong.

It should be possible, using the trace, to find out what's wrong and correct it (or produce a user-friendly exception)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The Applet should either start up or a clear error message should be produced in an appropriate exception.
ACTUAL -
BOOM!
See trace.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
java.lang.NullPointerException

            at sun.plugin.net.proxy.PluginProxyManager.getProxyInfo(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.connectSetup(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.connect(Unknown Source)

            at sun.plugin.net.protocol.http.HttpURLConnection.getInputStream(Unknown Source)

            at sun.plugin.net.protocol.http.HttpUtils.followRedirects(Unknown Source)

            at sun.plugin.cache.CachedJarLoader.download(Unknown Source)

            at sun.plugin.cache.CachedJarLoader.load(Unknown Source)

            at sun.plugin.cache.JarCache.get(Unknown Source)

            at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)

            at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)

            at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:580)

            at sun.misc.URLClassPath$JarLoader.<init>(URLClassPath.java:543)

            at sun.misc.URLClassPath$3.run(URLClassPath.java:321)

            at java.security.AccessController.doPrivileged(Native Method)

            at sun.misc.URLClassPath.getLoader(URLClassPath.java:310)

            at sun.misc.URLClassPath.getLoader(URLClassPath.java:287)

            at sun.misc.URLClassPath.getResource(URLClassPath.java:157)

            at java.net.URLClassLoader$1.run(URLClassLoader.java:192)

            at java.security.AccessController.doPrivileged(Native Method)

            at java.net.URLClassLoader.findClass(URLClassLoader.java:188)

            at sun.applet.AppletClassLoader.findClass(AppletClassLoader.java:146)

            at java.lang.ClassLoader.loadClass(ClassLoader.java:306)

            at sun.applet.AppletClassLoader.loadClass(AppletClassLoader.java:118)

            at java.lang.ClassLoader.loadClass(ClassLoader.java:251)

            at sun.applet.AppletClassLoader.loadCode(AppletClassLoader.java:577)

            at sun.applet.AppletPanel.createApplet(AppletPanel.java:710)

            at sun.plugin.AppletViewer.createApplet(Unknown Source)

            at sun.applet.AppletPanel.runLoader(AppletPanel.java:639)

            at sun.applet.AppletPanel.run(AppletPanel.java:319)

            at java.lang.Thread.run(Thread.java:595)



REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
Fumble with the server settings