Does not work even in Server Engine Version 7.5.5 ? It throws this error:

Directory AddRowButton Add-on
1

Does not work even in Server Engine Version 7.5.5 ?

It throws this error:
java.lang.NullPointerException at com.vaadin.data.util.BeanItem. (BeanItem.java: 61) at
com.vaadin.tatu.addrowbutton.AddRowButton$1.buttonClick(AddRowButton.)…