add a new variable 

no 

yes 

remove/rename a non-private variable 

no 

no 

remove/rename a private variable 

yes 

yes 

change final var default value 

no 

yes 

change non-final var default value 

yes 

yes 

non-final to final 

no 

yes 

final to non-final 

yes 

yes 

non-abstract to abstract 

no 

yes 

abstract to non-abstract 

yes 

yes 

more restrictive access 

no 

no 

less restrictive access 

no  

yes