Does Java license allow other companies to create their own versions of Java language or just implement it accurately? Same question about JVM.

I heard about Sun suing Microsoft for changing their .NET version of Java implementation and Java for Google Android, but I just can't grasp the whole concept as a totality.


Question: how to pass value from visual force page (InputField) to controller?
Answer: When you submit the page, Visualforce will update the OwnerId field of your opportunity object a automatically for you. If you want to use that value elsewhere (e.g. in a save method), you can just reference the value directly:

Id newApproverId = a.OwnerId;
...


and you can query for the corresponding name (if you need that):

String newApproverName = [select Name from User where Id = :a.OwnerId].Name;
...