NPE during deploy whith empty paramter from TK variable assignment tab.

 A flow with the R node gives a null-pointer exception during deploy when a vatiable is assigned that is not a part of a dataFram (R Dataframe Name attribute is left empty).

In the onInitialize method in RNode.java the parameters are stored in String vars and then checked with the isEmpty() function. However, when a paramer is not supplied, the String var is null and the call to isEmpty() rsult in an NPE.

I have changed the code to first check the String var for null, this solved the problem and either the correct message is given (if the parameter is mandatory) or the deploy succeeds and the node works. This is done for the vars dataFrame, name and xpathExpression, of instance:

if (name.isEmpty()) {

is changed to

if (name == null || name.isEmpty()) {

The isEmpty function seems needless, how do I get an empty string in a parameter?