You are probably getting warnings because you are using raw types - those are generic types which you are using without specifying a type parameter.
You are for example using Vector, but you don't specify the type parameter. Instead of
you should have used:
If you're unfamiliar with generics, see
Lesson: Generics in Oracle's Java Tutorials.
Another thing (which is not the cause of the compiler warnings): class Vector is a legacy collection class. You should use the newer class ArrayList instead of Vector.