Re: Strange NullPointerException

On Fri, 2004-03-19 at 20:55, "Gonçalo E.D. Luiz" wrote:
> Hello. I've been away for some time, but now I'm Back :P
> 
> I'm getting a really wierd problem on generated proxy class. The 
> generated code is as follows (except for System.out.println that I have 
> added for some debug):
> 
>    public void run() {
>        System.out.println("Tou no run do proxy !!!!!!!!!");
>       try {
>          System.out.println("O link e " + link);
>          System.out.println("O this e : " + this);
>          Object target = link.fetch (this, Lock.LEVEL_WRITE);
>          System.out.println("O target e " + target);
>          if (target!=null) {
>             ((kernel.ExecutionElement) target).run();
>          } else {
>             Object[] args   = {};
>             Object   result = link.invoke(this, 12, args, Lock.LEVEL_WRITE);
>          }
>       } catch (ExceptionInOzoneObjectException e) {
>          Throwable ee = e.getCause();
>         
>          // Hope that the compiler is not so smart and detect these 
> statements as unreachable if these exceptions are already matched above
>          if (ee instanceof RuntimeException) {
>              throw (RuntimeException) ee;
>          }
>         
>          if (ee instanceof Error) {
>              throw (Error) ee;
>          }
>         
>          throw e; // Unhandled exception.
>       } catch (RuntimeException e) {
>          e.fillInStackTrace();
>          throw e;
>       } catch (Exception e) {
>          e.fillInStackTrace();
>          throw new UnexpectedException (e.toString());
>       }
>    }
> 
> On the STDOUT I'm getting the following:
>      [java] Tou no run do proxy !!!!!!!!!
>      [java] O link e org.ozoneDB.Database@13e0aba
>      [java] O this e : class kernel.ExecutionElement_Proxy remoteID:113
>      [java] java.lang.NullPointerException
>      [java]     at kernel.ExecutionElement_Proxy.run(Unknown Source)
>      [java]     at 
> EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run(Po
> oledExecutor.java:725)
>      [java]     at java.lang.Thread.run(Thread.java:534)
> 
> 
> I'm running this via a PooledExecutor, thats because the stack trace 
> reports it. However, because of the System.out.println one can state 
> that the problem is in the link.fetch method. The "this" object is, as 
> printed, kernel.ExecutionElement_Proxy remoteID:113.
> 
> What am I doing wrong ?
> 
> Please be as fast as you can, I'm going mad.

When something strange happens to me, I always
- build all classes (i.e. rm -rf classes/*)
- run opp
- restart the database

99 out of a 100 times my problems go away.

Cheers,
Leo

-- 
    .--.      .---------------.----------------------------------------.
   |o_o |     | Leo Mekenkamp | Free, as in 'beer' and as in 'speech': |
   |:_/ |     | +31 641234919 | office software  http://openoffice.org |
  //   \ \    |               | 100% java odbms    http://ozone-db.org |
 (|     | )   | Long Live Tux | e-mail & browser    http://mozilla.org |
/'\_   _/`\   |               | operating system      http://linux.org |
\___)=(___/   `---------------'----------------------------------------'



-------------------------------------------------------
This SF.Net email is sponsored by: IBM Linux Tutorials
Free Linux tutorial presented by Daniel Robbins, President and CEO of
GenToo technologies. Learn everything from fundamentals to system
administration.http://ads.osdn.com/?ad_id70&alloc_id638&op=click