Problem Launching Java Applet with Plug-in: Version 1.4.2_01

Question

Hello out there:
I recently installed j2re-1.4.2_01 on my home computer but have been unable to access Web sites emmploying JAva applets. The following is an email exchange with Jeff Hall of Lowell Observatory, manager of an educational site hosted by Lowell, trying to resolve my problem. The messages are better understood if read in reverse order.
I'm hoping that someone will recognize the source of my problem and can recommmend a solution. I would appreciate any help offered.
Thanks,
Mike Coucke
Hi Jeff:
Well, I guess the problem lies with me somewhere. Here's my answer/status to your questions/suggestions:
1) I'm using MS Windows Me version 4.90.3000
2) I do have the directory C:\Windows\.jpi_cache\jar\, but the only thing in it is an empty folder labeled "1.0". The file LP.jar does not exist anywhere on my hard drive.
3) I tried several game sites that utilized Java applets and got the same results: the Java cup in the upper left corner followed a few seconds later by the red "X". So, evidently the problem is somewhere on my end.
I'm going to post our email exchanges in a Java Users Forum managed by Sun to see if anyone out there can solve my problem. However, if you have any more suggestions, I'll be glad to try them.
Thanks for the help.
Mike Coucke
[email protected]
----- Original Message -----
From: "Jeffrey Hall" <[email protected]>
To: "'Mike Coucke'" <[email protected]>
Sent: Friday, September 05, 2003 1:02 PM
Subject: RE: Registration with Lowell Education Online
Mike,
Rats! What version of Windows are you using? It's a little strange to
see the user directory set to C:\Windows; if you're using XP, I'd expect
it to be something like C:\Documents and Settings\Mike Coucke. In any
event, the output that is of concern is these two lines:
java.lang.ClassNotFoundException: LPRemote.class
Caused by: java.net.UnknownHostException: proxy
It looks like your browser is not finding our server's IP when it comes
time to download the necessary Java code.
LPRemote.class is the fundamental code that runs LOPARC, and your
browser should be downloading it automatically when you click connect.
LPRemote.class is stored along with a bunch of other classes in a file
called "LP.jar" that you download from our server. So, if you go to C:
in Windows Explorer and do a file search for LP.jar, you should find it.
On my machine, it's stored in a directory called ".jpi_cache\jar\" in my
user home directory. Let me know if you have this file, or the
jpi-cache directory.
One other thing you might try is going to a different site that you know
uses Java applets -- I think some of the online game rooms at Yahoo use
Java. See if other sites that use Java load correctly. Then we'll know
if it's our server specifically, or a more general problem on your end.
Jeff Hall
Lowell Observatory
Hello Jeff:
I still have the Java "blues". I followed your instructions, but am still unable to launch a LOPARC session. After an initial failure, I uninstalled all three Java versions I had (1.4.0, 1.4.1, 1.4.2), then reinstalled 1.4.2_01 from the Sun website.
Now, when I try to launch LOPARC, I initially get a blank window with the Java cup in the upper left corner. After about 20 seconds, the cup changes to a red "X". During those 20 seconds, the following appear in the IE message bar at the bottom of the window: "Applet LPRemote notinited" (their spelling) which changes to "Loading Java Applet Failed..." when the red "X" appears.
Following is a copy of the log from my Java Console during all of this:
Java(TM) Plug-in: Version 1.4.2_01
Using JRE version 1.4.2_01 Java HotSpot(TM) Client VM
User home directory = C:\WINDOWS
Proxy Configuration: Manual Configuration
Proxy: http=proxy,https=proxy,ftp=proxy,gopher=proxy
Proxy Overrides:
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to <n>
load: class LPRemote.class not found.
java.lang.ClassNotFoundException: LPRemote.class
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.net.UnknownHostException: proxy
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.plugin.net.protocol.http.HttpClient.doConnect(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.http.HttpClient.privilegedOpenServer(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.<init>(Unknown Source)
at sun.net.www.http.HttpClient.<init>(Unknown Source)
at sun.plugin.net.protocol.http.HttpClient.<init>(Unknown Source)
at sun.plugin.net.protocol.http.HttpClient.New(Unknown Source)
at sun.plugin.net.protocol.http.HttpURLConnection.createConnection(Unknown Source)
at sun.plugin.net.protocol.http.HttpURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.applet.AppletClassLoader.getBytes(Unknown Source)
at sun.applet.AppletClassLoader.access$100(Unknown Source)
at sun.applet.AppletClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
... 10 more
I followed this up by executing the following three console commands:
"dump system properties"
"dump classholder list"
"dump thread list"
and obtained the following listings:
Dump system properties ...
acl.read = +
acl.read.default =
acl.write = +
acl.write.default =
application.home = C:\PROGRA~1\JAVA\J2RE14~1.2_0
awt.toolkit = sun.awt.windows.WToolkit
browser = sun.plugin
browser.vendor = Sun Microsystems, Inc.
browser.version = 1.1
deployment.javaws.cache.dir = C:\WINDOWS\.javaws\cache
deployment.javaws.jre.0.enabled = true
deployment.javaws.jre.0.location = http://java.sun.com/products/autodl/j2se
deployment.javaws.jre.0.osarch = x86
deployment.javaws.jre.0.osname = Windows
deployment.javaws.jre.0.path = C:\Program Files\Java\j2re1.4.2_01\bin\javaw.exe
deployment.javaws.jre.0.platform = 1.4
deployment.javaws.jre.0.product = 1.4.2_01
deployment.javaws.jre.0.registered = true
deployment.javaws.version = javaws-1.4.2_01
deployment.system.cacerts = C:\PROGRA~1\JAVA\J2RE14~1.2_0\lib\security\cacerts
deployment.system.home = C:\WINDOWS\Sun\Java\Deployment
deployment.system.jssecacerts = C:\PROGRA~1\JAVA\J2RE14~1.2_0\lib\security\cacerts
deployment.system.profile = C:\WINDOWS
deployment.system.security.policy = file:/C:/WINDOWS/Sun/Java/Deployment/security/java.policy
deployment.user.cachedir = C:\WINDOWS\Application Data\Sun\Java\Deployment\cache
deployment.user.certs = C:\WINDOWS\Application Data\Sun\Java\Deployment\security\deployment.certs
deployment.user.extdir = C:\WINDOWS\Application Data\Sun\Java\Deployment\ext
deployment.user.home = C:\WINDOWS\Application Data\Sun\Java\Deployment
deployment.user.jssecerts = C:\WINDOWS\Application Data\Sun\Java\Deployment\security\deployment.jssecerts
deployment.user.logdir = C:\WINDOWS\Application Data\Sun\Java\Deployment\log
deployment.user.profile = C:\WINDOWS\Application Data
deployment.user.security.policy = file:/C:/WINDOWS/Application%20Data/Sun/Java/Deployment/security/java.policy
deployment.user.tmpdir = C:\WINDOWS\Application Data\Sun\Java\Deployment\cache\tmp
file.encoding = Cp1252
file.encoding.pkg = sun.io
file.separator = \
file.separator.applet = true
http.agent = Mozilla/4.0 (Windows Me 4.90)
http.auth.serializeRequests = true
https.protocols = SSLv3,SSLv2Hello
java.awt.graphicsenv = sun.awt.Win32GraphicsEnvironment
java.awt.printerjob = sun.awt.windows.WPrinterJob
java.class.path = C:\PROGRA~1\JAVA\J2RE14~1.2_0\classes
java.class.version = 48.0
java.class.version.applet = true
java.endorsed.dirs = C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\endorsed
java.ext.dirs = C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\ext
java.home = C:\PROGRA~1\JAVA\J2RE14~1.2_0
java.io.tmpdir = C:\WINDOWS\TEMP\
java.library.path = D:\PROGRAM FILES\INTERNET EXPLORER 6;.;C:\WINDOWS\SYSTEM;C:\WINDOWS;D:\PROGRA~1\INTERN~1;;C:\WINDOWS;C:\WINDOWS\COMMAND
java.protocol.handler.pkgs = sun.plugin.net.protocol|sun.plugin.net.protocol
java.runtime.name = Java(TM) 2 Runtime Environment, Standard Edition
java.runtime.version = 1.4.2_01-b06
java.specification.name = Java Platform API Specification
java.specification.vendor = Sun Microsystems Inc.
java.specification.version = 1.4
java.util.prefs.PreferencesFactory = java.util.prefs.WindowsPreferencesFactory
java.vendor = Sun Microsystems Inc.
java.vendor.applet = true
java.vendor.url = http://java.sun.com/
java.vendor.url.applet = true
java.vendor.url.bug = http://java.sun.com/cgi-bin/bugreport.cgi
java.version = 1.4.2_01
java.version.applet = true
java.vm.info = mixed mode
java.vm.name = Java HotSpot(TM) Client VM
java.vm.specification.name = Java Virtual Machine Specification
java.vm.specification.vendor = Sun Microsystems Inc.
java.vm.specification.version = 1.0
java.vm.vendor = Sun Microsystems Inc.
java.vm.version = 1.4.2_01-b06
javaplugin.maxHeapSize = 96m
javaplugin.nodotversion = 142_01
javaplugin.proxy.config.list = http=proxy,https=proxy,ftp=proxy,gopher=proxy
javaplugin.proxy.config.type = manual
javaplugin.version = 1.4.2_01
javaplugin.vm.options = -Djava.class.path=C:\PROGRA~1\JAVA\J2RE14~1.2_0\classes -Xbootclasspath/a:C:\PROGRA~1\JAVA\J2RE14~1.2_0\lib\plugin.jar -Xmx96m -Djavaplugin.maxHeapSize=96m -Xverify:remote -Djavaplugin.version=1.4.2_01 -Djavaplugin.nodotversion=142_01 -Dbrowser=sun.plugin -DtrustProxy=true -Dapplication.home=C:\PROGRA~1\JAVA\J2RE14~1.2_0 -Djava.protocol.handler.pkgs=sun.plugin.net.protocol
line.separator = \r\n
line.separator.applet = true
os.arch = x86
os.arch.applet = true
os.name = Windows Me
os.name.applet = true
os.version = 4.90
os.version.applet = true
package.restrict.access.netscape = false
package.restrict.access.sun = true
package.restrict.definition.java = true
package.restrict.definition.netscape = true
package.restrict.definition.sun = true
path.separator = ;
path.separator.applet = true
sun.arch.data.model = 32
sun.boot.class.path = C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\rt.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\i18n.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\sunrsasign.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\jsse.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\jce.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\lib\charsets.jar;C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\classes;C:\PROGRA~1\JAVA\J2RE14~1.2_0\lib\plugin.jar
sun.boot.library.path = C:\PROGRAM FILES\JAVA\J2RE1.4.2_01\bin
sun.cpu.endian = little
sun.cpu.isalist = pentium i486 i386
sun.io.unicode.encoding = UnicodeLittle
sun.java2d.fontpath =
sun.net.client.defaultConnectTimeout = 120000
sun.os.patch.level =
trustProxy = true
user.country = US
user.dir = C:\WINDOWS\Desktop
user.home = C:\WINDOWS
user.language = en
user.name = Michael G. Coucke
user.timezone =
user.variant =
Done.
Dump classloader list ...
codebase=http://kraken.lowell.edu/, key=http://kraken.lowell.edu/,IONJava/classes/ion_16.jar,IONJava/classes/LP.jar, zombie=false, cache=true, refcount=1, info=sun.plugin.ClassLoaderInfo@109de5b
Done.
Dump thread list ...
Group main,ac=11,agc=2,pri=10
main,5,alive
AWT-Windows,6,alive,dameon
AWT-Shutdown,5,alive
Java2D Disposer,10,alive,dameon
AWT-EventQueue-0,6,alive
Group Plugin Thread Group,ac=3,agc=0,pri=10
Main Console Writer,6,alive
AWT-EventQueue-1,6,alive
TimerQueue,5,alive,dameon
Group http://kraken.lowell.edu/-threadGroup,ac=2,agc=0,pri=4
thread applet-LPRemote.class,4,alive
AWT-EventQueue-2,4,alive
Done.
I'm not a Java expert, so this may be more information than you ever wanted to see.
Once again, I hope that you can help. My experience has been that I usually have some obscure option set incorrectly and that causes me great grief.
Thanks fo your help,
Mike Coucke
[email protected]
----- Original Message -----
From: "Jeffrey Hall" <[email protected]>
To: "'Mike Coucke'" <[email protected]>
Sent: Thursday, September 04, 2003 11:48 AM
Subject: RE: Registration with Lowell Education Online
Hi Mike,
Try it now. I think this problem has arisen because Sun just
released a new version of the Plug-in (1.4.2), and when we released the
public beta of LOPARC, only one relevant version (1.4.0) was available
and the LOPARC code was written to look for that by default. I have
just recoded the relevant routines so they should now cause your browser
to simply pick up the latest 1.4 version of the Plug-in you have
installed, whatever it is. I "broke" Java on my machine to replicate
your problem, and the code I inserted today did fix it. Hopefully it
will have the same effect for you. I am running IE 6 and plugin
1.4.2_01 (as accessed via Tools->Sun Java Console).
One broader problem: some (non-LOPARC-specific) users on the Sun
forums have reported the "JRE collision" you are seeing when multiple
versions of the Plug-in are installed on the same machine. So if the
fix I made to our code doesn't work, one option would be to uninstall
all Java components from your computer and do a fresh install of the
latest runtime environment.
Let me know how/if this works. Thanks for the feedback and for your
patience.
Best regards,
Jeff Hall
Lowell Observatory
-----Original Message-----
From: Mike Coucke [mailto:[email protected]]
Sent: Wednesday, September 03, 2003 6:30 PM
To: [email protected]
Subject: Re: Registration with Lowell Education Online
Hello Jeff:
So far, I have been unable to launch a LOPARC session. I repeatedly
get the following error message:
"Exception: java.lang.ClassNotFoundException: LPRemote.class"
My browser is MS Internet Explorer version 6.0.2800.1106 Initially I was
using Java Plug-In version 1.4.1 and received the error message. I went
to the Sun website and downloaded/installed Java Plug-In version 1.4.2
and still get the message.
Before I try to launch LOPARC, I can select Tools->Sun Java Console from
IE's pull down menu to check my Java Plug-In version. When I try to
launch LOPARC, I get the following message:
"Applet(s) in this HTML page requires a version of Java different from
the one the browser is currently using. In order to run the applet(s)
in this HTML page, a new browser session is required, press 'Yes' to
start a new browser session." If I select 'No', I get the following
message: "Java Plug-in detected JRE collission"
If I select 'Yes', a new browser window opens and then I get the first
message above.
Can you help?
Mike Coucke
[email protected]
----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Monday, September 01, 2003 5:30 PM
Subject: Registration with Lowell Education Online
September 1, 2003
Dear Michael Coucke:
Thank you for registering with Lowell Observatory's online education
site. We hope you enjoy using it and visit regularly as we continue to
expand its features and capabilities. This is a one-time welcoming
email.
For your records, your user ID is xxxxx, and your password is #########.
You'll need to supply these each time you log in.
This site gives you access to research-grade equipment including a 16"
telescope, CCD detector, and image processing software. Our online
archive of data is now available 24/7. The telescope will be opening to
our onsite users in May, and on select nights to the Internet at large
in June.
We have designed this site so you don't need a huge monitor or a
supercomputer to use it. All pages are viewable on screens running at
800x600 resolution or higher. To use LOPARC, you'll need a Java-enabled
browser with the Java 1.4 plug-in installed. If you don't have the
plug-in, you'll be prompted to download it the first time you attempt to
connect. This is an admittedly large (9 MB) but one-time-only download.
This site works correctly under Internet Explorer version 5 or higher.
If you use Netscape, you must be running version 6 or higher, and
display or applet behavior anomalies may occur.
If at any time you can't connect to our server, simply try again later.
We do experience several power outages each year, particularly during
Flagstaff's summer thunderstorm season. Our server is fully protected
and backed up, and can be quickly brought back on line, but any active
user sessions will be lost. Thanks for your patience during these
inevitable downtimes.
Your questions, comments, suggestions, and bug reports about this site
are always welcome. On behalf of the LOPARC development team, thanks
for signing up!
Jeffrey Hall
Assistant Research Scientist
Associate Director, Education and Special Programs
Lowell Observatory
Flagstaff, Arizona

Answer 1

Hi Mike,
I see this in your logs:
Java(TM) Plug-in: Version 1.4.2_01
Using JRE version 1.4.2_01 Java HotSpot(TM) Client VM
User home directory = C:\WINDOWS
Proxy Configuration: Manual Configuration
Proxy: http=proxy,https=proxy,ftp=proxy,gopher=proxy
Proxy Overrides:
I just helped my Dad set up his computer with a new
cable modem, and had the situation where we couldn't
access any secure Web sites. The cable folks had us
disable the proxy. It looks like the error message is
saying it can't find your proxy server, and the logs
you posted say that you've decided to configure your
proxy manually, rather than using the settings from
IE (which is how mine is set up in the plugin
control panel.)
Could that be the problem?
--Steve