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Message:

Class Loading Problem----Illegal constant pool type & Illegal UTF8 string in constant pool

Posted by Dipak Sahoo on July 12, 2000 at 7:13 PM

Check you might upload the file using FTP (ASCII) try to upload in binary..

> Hello,

> I have a strange problem with my custom remote class loading in my Jini
> project. I need to upload some classes to the http server, so the Jini
> client can
> retrieve those classes via a custom remote class loader.

> The problem is:

> Sometimes the classes are downloaded smoothly and the Jini client works
> fine,
> however, when I run a second time, "Illegal constant pool type" or
> "Illegal UTF8
> string in constant pool" will appear. Then I run a third time, fail in
> the same way,
> run a fourth time, fail in the same way, run a fifth time, everything is
> fine!

> Since this problem is so unstable that I have no idea if this is the
> problem with
> my class loader or this is a problem with file transmission.

> Attached please find the original error messages.

> Your help is going to be highly appreciated.

> Tao

>
> Loading from URL:
> http://xxx.xxx.xxx.xxx/info/grads/tyt/classes/jatwing/Wrapper.class
> The loaded class is instantiated successfully.
> Loading from URL:
> http://xxx.xxx.xxx.xxx/info/grads/tyt/classes/cruiser2/Cruiser.class
> java.lang.ClassFormatError: cruiser2/Cruiser (Illegal constant pool
> type)
> at java.lang.ClassLoader.defineClass0(Native Method)
> at java.lang.ClassLoader.defineClass(ClassLoader.java, Compiled
> Code)
> at java.lang.ClassLoader.defineClass(ClassLoader.java, Compiled
> Code)
> at ...

> Loading from URL:
> http://xxx.xxx.xxx.xxx/info/grads/tyt/classes/jatwing/Wrapper.class
> The loaded class is instantiated successfully.
> Loading from URL:
> http://xxx.xxx.xxx.xxx/info/grads/tyt/classes/cruiser1/Cruiser.class
> java.lang.ClassFormatError: cruiser1/Cruiser (Illegal UTF8 string in
> constant pool)
> at java.lang.ClassLoader.defineClass0(Native Method)
> at java.lang.ClassLoader.defineClass(ClassLoader.java, Compiled
> Code)
> at java.lang.ClassLoader.defineClass(ClassLoader.java, Compiled
> Code)
> at ....