I have an automation script that I am working on that implements a REST API request. I'm having a problem trapping exceptions coming from java method calls. In this case, I am calling the add() method on an mbo opened on the PLUSDESTVERSION table. There is a custom java validation that throws an exception if the value assigned to the WORKGROUP field isn't a valid record. I have added multiple levels of "try/except" blocks around the add() call, but the except blocks aren't getting invoked, and my REST API call is returning a 400 status, with the response JSON body set to the data from the java error.

Here is the code:

            try:
                version = versionSet.add()
                version.setValue("CONTRIBUTIONMETHOD", "N")
                version.setValue("APPLYCONTRIBUTION", "N")
                log("Before setValue(WORKGROUP)")
                try:
                    version.setValue("WORKGROUP", parentWO.getString("OWNERGROUP"))
                except Exception as addEx:
                    log_error("EXCEPTION during version.setValue(): {}".format(str(addEx)))
                    raise Exception("EXCEPTION during version.setValue(): {}".format(str(addEx)))
                
                log("After setValue(WORKGROUP)")
                version.setValue("OVERHEADTYPE", parentWO.getString("OPSSITEID"))
                if ogsLvInitiatedCue == "Y":
                    version.setValue("STORELOC", storeLoc)
                    if opsSiteId == "ONG":
                        # Set default for ONG only
                        log("Setting PLUSDESTVERSION.OGSREIMBURSABLE for ONG")
                        version.setValue("OGSREIMBURSABLE", "No")
                    
                versionSet.save()
            except Exception as addEx:
                log_error("EXCEPTION during versionSet.add(): {}".format(str(addEx)))
                raise Exception("EXCEPTION during versionSet.add(): {}".format(str(addEx)))

Rather than my exception message appearing in the REST call's response body, I'm getting this:

Java and Python both have an Exception class. What your code is catching is the Python Exception.

To resolve this conflict, import the Java Exception with an alias, like this:

from java.lang import Exception as JavaException

Then, have an except clause for each of Exception and JavaException.

Thank you for the information about the Java exception class. Can you share an example that shows how to use the class around a Java method call?

Thank you!

When I need to catch a Java exception, it often looks like this:

from java.lang import Exception as JavaException
logger = mbo.getMboLogger()
try:
    logger.debug("Do something that could throw an exception")
except Exception as e:
    logger.error("Python Exception: {}".format(str(e)))
except JavaException as e:
    logger.error("Java Exception: {}".format(e.getMessage()), e)

------------------------------
Blessings,
Jason Uppenborn
Sr. Technical Maximo Consultant
Cohesive
------------------------------

When catching JavaExceptions, i often tend to use Throwable instead of Exception. Some external libs extends its Exceptions from it.

So i end up more with this:

from java.lang import Throwable
logger = mbo.getMboLogger()
try:
    logger.debug("Do something that could throw an exception")
except Exception as e:
    logger.error("Python Exception: {}", str(e))
except Throwable as e:
    logger.error("Java Exception: {}".format(e.getMessage()), e)

from java.lang import Exception as JavaExceptionlogger = mbo.getMboLogger()try:    logger.debug("Do something that could throw an exception")except Exception as e:    logger.error("Python Exception: {}", str(e))except JavaException as e:    logger.error("Java Exception: {}".format(e.getMessage()), e)