Exercise $1$: Java Generics

Task $1$: Define a generic class named PairBox that can store a pair of objects of different types. The class should have two type parameters: T for the first type and U for the second type. Implement methods to set and get these objects.

Hints:

$$ Use angle brackets to specify the type parameters in your class definition, e$.$g$.,$ class PairBox.

$$ For setting objects, define two methods: one for each type. For getting objects, also define two methods.

$$ Ensure your class has private variables to store the objects and use the constructor to initialize them.

Task $2$: Implement a Generic Method

Create a utility class named BoxSwapper. Inside BoxSwapper, implement a static generic method named swap that swaps a second pair of similar elements inside a given PairBox.Due to type safety constraints, the swap method will only work with similar types stored in the PairBox.

Hints:

$$ Remember that generics provide compile$-$time type safety. When defining generic classes or methods, use type parameter$($s$)$ like $,$ where T stands for "Type".

$$ Your method should be defined with type parameters that match those of PairBox.

$$ Use the get and set methods of PairBox to perform the swap

Task $3$: Implement a Generic Interface

Define a generic interface named Transformer with one type parameter.

The interface should declare a method named transform that accepts and returns an object of the generic type. Implement this interface in a class, using a specific type $($e$.$g$.,$ Integer or String$),$ and provide the logic to transform the input in some way.

Hints

$$ Think about simple transformations, like negating a number or converting a string to uppercase.