Variables for Troubleshooting

To facilitate debugging, include output variables in the state code for an error message, a unique error ID, and a service code. If the state calls an external Web service, for example, the Web service can return a code in the service-code output variable.

// Define output variables

private static final OutputAttribute outErrMsg = 
                     new OutputAttribute("ERR_MSG", "Error Message");        
private static final OutputAttribute outErrUUID = 
                     new OutputAttribute("ERR_UUID", "Error Unique ID");        
private static final OutputAttribute outSvcCode = 
                     new OutputAttribute("SVC_CODE", "Service Code");        
    
// some code omitted here…    
        
@Override    
protected SmappState processStateLogic(…)    
{    
  // Logic implementation    
      
  try {            
    // Reset the error output variable    
    outErrMsg.setHoldValue("");        
    outErrUUID.setHoldValue("");        
    saveOutputAttributes();            
    return continueOk();
  }    
  catch (Exception ex) {            
    String uuid = UUID.randomUUID().toString();        
    log.error(ex.getMessage()+ " [UUID={}]", uuid);        
    outErrMsg.setHoldValue(message);    
    outErrUUID.setHoldValue(uuid);    
    saveOutputAttributes();            
    return continueFail();    
  } 
}