Unusual Error

[John Plond JORGENSEN <jjorge1@cs.mcgill.ca>]

>>>>> "howellc" == Christopher Howell <howellc@allegheny.edu> writes:

    howellc> During run-time I get an unusual error.  I am not
    howellc> sure if it has to do with Soot or not.  It is

    howellc> Aborting: can't find classfileboolean
    howellc> java.lang.SecurityException: Could not lockUser prefs.Lock file access denied

    howellc> I was just wondering if anyone has ever received
    howellc> this and how they were able to get rid of it.

My guess is that you're using Sun's JDK 1.4.x on Linux.

JDK 1.4.0 introduced a System and User Preferences system that I
really don't know anything about.  I've noticed, though, that
ever since I started using 1.4, I get lots of 

 java.util.prefs.FileSystemPreferences syncWorld
 WARNING: Couldn't flush system prefs: java.util.prefs.BackingStoreException: Couldn't get file lock.

in my browser's Java console when I run a particular applet. I
assumed that they were caused by the preferences system looking
for a file in which to store system-wide preferences, and
discovering the file doesn't exist.  I have been ignoring the
messages, and the applet has appeared to run correctly (though
there are reports that the messages may be associated with a
check that can exhaust a process's file handles under 1.4.0, but
perhaps not 1.4.1. See:

 http://forum.java.sun.com/thread.jsp?forum=27&thread=231280
 http://developer.java.sun.com/developer/bugParade/bugs/4666397.html
 http://docs.sun.com/source/816-7161-10/
)

So a quick fix might be to fall back to JDK 1.3.x, if there is
nothing in 1.4 that you really need. Otherwise, I suppose you
could try reading up on the preferences mechanism to figure out
what might be activating it.

The preferences mechanism is documented in 

 http://java.sun.com/j2se/1.4.1/docs/guide/lang/preferences.html
 http://java.sun.com/j2se/1.4.1/docs/api/index.html

The odd thing is that your message is about the User preferences
rather than the System preferences, since one would figure that
the user file should be readable and writable. Unless your
application is running inside a security sandbox that doesn't
allow it to access the user's files.

At any rate, I doubt that this problem has much to do with Soot
per se, but instead with some interaction between soot and the
environment in which you are running it. I'm pretty sure nothing
in soot uses java.lang.prefs.

-- 
John Jorgensen		jjorge1@cs.mcgill.ca