Getting information about exceptions thrown by called Java methods

When RPG calls a Java™ method that ends with an exception, RPG handles the Java exception and signals escape message RNX0301. This message has the string value of the Exception, but it does not have the trace information that is normally available when Java calls a method that ends with an exception.

If you want to see the Java exception trace information, do the following:
  1. ADDENVVAR ENVVAR(QIBM_USE_DESCRIPTOR_STDIO) VALUE('Y')
    Note: This step must be done before the JVM is started.
  2. Ensure that the os400.stderr option in your SystemProperties.default file is set to file:myfilename, for example os400.stderr=file:/home/mydir/stderr.txt. See Controlling how the Java Virtual Machine is set up.
    Note: This step must be done before the JVM is started.
  3. ADDENVVAR ENVVAR(QIBM_RPG_JAVA_EXCP_TRACE) VALUE('Y')
    Note: This step can be done at any time. To stop the exception trace being done by RPG, you can remove the environment variable, or set it to a value other than 'Y'.
  4. After the exception has occurred, the trace information will be in the file that you specified in the os400.stderr option.