Managing System errors related to web service

How can I manage any system error like null pointer exception to return my meaningful custom error if it is thrown. and also Managing Required/optional parameter error message: to show custom message rather than "invalid value for parameter ...."
1 answers

You could place the entire implementation of your published web service operation in another microflow. Then you could call that microflow using a microflow call activity with custom error handling to "catch" any system errors and then throw a custom error (e.g. using a Java action).

The default parameter error messages (such as errors for required values and wrong value types) are currently not configurable. However, you could always perform additional validation on the parameters in your microflow and throw custom errors for those.