The Java action is trying to work with an object that's not available, hence the NullPointerException. It tries to execute this action: getMemberType. I would suggest debugging with Eclipse to find out what's missing exactly and work your way through from there.
It's impossible to say what specific object is missing by looking at the stack trace. Perhaps someone else on the forum has more experience with this module than me and can tell you what object is missing.
That is a weird stacktrace that you are getting. A few questions to get you started.
-Yes, I am using latest Database Replication available in Mendix App store -Yes,I have sync my database (importing 557 table and 1157 column) and click on the save button -I am using Custom Type import to connect AS400 -I am still getting above error.