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appletviewer and java , not  finding/reading? files

tellurion
tellurion asked
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Last Modified: 2013-11-23
I have installed jdk1.1.1 , using windows 95 , Packard Bell system . I have written and compiled an applet called "JavaNow" it is essintally the "HelloWorld" applet except from the book Java Now . javac successfuly compiled the program into a .class file , I wrote the html file and saved as .html . The problem is when I try to view it with appletviewer the appletviewer window opens with the message " Start: applet not inialized ." at the bottem , the title bar of the window says "JavaNow.class" . When the window first opens instead of "applet not initalized" for about 1 second it flickers something to the effect of " applet starting " . Then when I close the window this message is on the screen : ( the first lines are my comman line entry)



[WINDOWS] C:\>jdk1.1.1\bin\appletviewer jdk1.1.1\learn\JavaNow.html
java.io.FileNotFoundException: \C:\\JavaNow.class
        at java.io.FileInputStream.<init>(FileInputStream.java:64)
        at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection
.java:150)
        at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLCon
nection.java:170)
        at sun.applet.AppletClassLoader.loadClass(AppletClassLoader.java:115)
        at sun.applet.AppletClassLoader.loadCode(AppletClassLoader.java:259)
        at sun.applet.AppletClassLoader.loadCode(AppletClassLoader.java:352)
        at sun.applet.AppletPanel.runLoader(AppletPanel.java:419)
        at sun.applet.AppletPanel.run(AppletPanel.java:223)
        at java.lang.Thread.run(Thread.java:474)
File not found when looking for: JavaNow
java.lang.NullPointerException
        at sun.applet.AppletPanel.runLoader(AppletPanel.java:419)
        at sun.applet.AppletPanel.run(AppletPanel.java:223)
        at java.lang.Thread.run(Thread.java:474)

One note which my be important : When I open the JavaNow.html  file with my NS browser it is displayed correctly .

I have a simmular problem with the java interpreter . Please let me know if thes are seperate problems , thus seperate questions and I will ask the second one in its own post . I will include it here because I think they are both simptomes of the same problem .
When I try to run a basic app called "HelloJava" which has been successfuly compiled into *.class I get the following error message :( with the first lines being my command line entry )
[WINDOWS] C:\>jdk1.1.1\bin\java jdk1.1.1\learn\HelloJava\HelloJava
Invalid class name 'jdk1.1.1\learn\HelloJava\HelloJava'
usage: java [-options] class

where options include:
    -help             print out this message
    -version          print out the build version
    -v -verbose       turn on verbose mode
    -debug            enable remote JAVA debugging
    -noasyncgc        don't allow asynchronous garbage collection
    -verbosegc        print a message when garbage collection occurs
    -noclassgc        disable class garbage collection
    -cs -checksource  check if source is newer when loading classes
    -ss<number>       set the maximum native stack size for any thread
    -oss<number>      set the maximum Java stack size for any thread
    -ms<number>       set the initial Java heap size
    -mx<number>       set the maximum Java heap size
    -classpath <directories separated by semicolons>
                      list directories in which to look for classes
    -prof[:<file>]    output profiling data to .\java.prof or .\<file>
    -verify           verify all classes when read in
    -verifyremote     verify classes read in over the network [default]
    -noverify         do not verify any class

 

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1. The Applet viewer expects a .class file, not a .html file. That's why Netscape is working - you're giving it a .html file which it expects. Try "c:>appletviewer JavaNow"

2. Similar problem. As the error message said, you need to type "java HelloJava" at the prompt, not just "HelloJava". You can't run a .class file - they are not executable. You run the java virtual machine, and give it your .class file as a command line parameter. Hence, "c:> java HelloJava"
How about the CLASSPATH environemt variable? I believe it is not required, but if it is set incorrectly then you will need to either unset it or set it correctly. There is a README that gets installed in the jdk1.1.1 directory for your Windows NT installation which discusses this in more detail. It would explain both of your problems.

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Have you tried using the CODEBASE parameter in the APPLET tag?

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