where does system.out.println output goes in oracle java class

Question

I have loaded a java class into oracle using loadjava utility

This class has some system.out.println messages.

When I execute a method from this class I want

Answer 1

System.out and System.err writes to the current trace files

You can enable output to SQL*Plus or similar with

set serveroutput on size 10000

exec dbms_java.set_output(10000)

See the Java Developer's Guide here

That said you should ask yourself, what do I want to log, that my client would not like to see returned in the interface to my procedure. The answer to that is usually nothing.

I have been able to setup http://www.slf4j.org/ with a jdbc database appender (unsure of the specifics)