as far as I know interface is there to support mulitiple inheritence like thing....and it'll consists of all abstract methods.....but when i looked at some interfaces in api like Connection,ResultSet they are calling some methods(like normal classes) and the methods are returning some values too..
for example:
ResultSet rs=Stmt.executeQuery("select ....................");
if(rs.next()) (rs.next method is returning boolean, but resultset is interface
)..... my doubt is where and how all these methods for interfaces in api are implemented(sorry if i am missing any basic thing)
thanx in advance