This week's book giveaway is in the General Computing forum. We're giving away four copies of Arduino in Action and have Martin Evans, Joshua Noble, and Jordan Hochenbaum on-line! See this thread for details.
Why the following code doesnt show any conflict since both, method1 in iface1 and aclass1 have the same name and must be implemented by class test1a. It seems that test1a is implementing the aclass1 method and not the iface1, why?
There is only one way you could have a conflict: if the two methods did not have compatible intentions. I have amended your code to introduce such an incompatibility By the way: please use spaces, not tabs, for indenting.