Debugging Techniques

Until Java IDEs and JVMs support remote debugging, you can adopt several techniques for debugging your CORBA client and server code.

1. Do standalone ORB debugging using one machine and ORB tracing.

   Debug in a single address space, on a client system. Use of an IDE for client or server debugging is optional, though highly desirable.

2. Use Oracle8i trace files.

   The output of System.out.println() in the Oracle8i ORB goes to the server trace files. The directory for trace files is a parameter specified in the INITSID.ORA file. Assuming a default install of the product into a directory symbolically named ORACLE_HOME, then the trace file would appear as

   ${ORACLE_HOME}/admin/<SID>/bdump/ORCL_s000x_xxx.trc
   
   

   where ORCL is the SID, and x_xxx represents a process ID number. Do not delete trace files after the Oracle instance has been started, or no output is written to a trace file. If you do delete trace files, stop and then restart the server.

3. Use a single Oracle MTS server.

   For debugging only, set the MTS_SERVERS parameter in your INITSID.ORA file to MTS_SERVERS = 1, and set the MTS_MAX_SERVERS to 1. Having multiple MTS servers active means that a trace file is opened for each server process, and thus the messages get spread out over several trace files, as objects get activated in more than one session.

4. Use "printback" to redirect System.out.

   You can use the technique demonstrated in the example program "printback" to redirect System.out and System.err println's to the client system console.

Perhaps the best way to develop and debug Java/CORBA code is to use either the second or third technique described above, then deploy into the Oracle8i ORB.

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