Implementing methods from an interface but with different parameters

Question

I am looking for a good way to have different implementations of the same method which is defined in an interface but with different parameter types. Would this be possible?

Answer 1

Here's an example of Generics

Database

public interface Database<T> {
    public T createNode(...);
    public void modifyNode(T id, ...);
    ...  
}

Database1

class Database1 implements Database<Long> { 
    @Override
    public Long createNode(...) { 
        ...
        long result = // obtain id of created node
        return result;
    }

    @Override
    public void modifyNode(Long id, ...) { 
        ...
        // use id
    }
}

Database2

public class Database2 implements Database<SomeObject> { 
    @Override
    public SomeObject createNode(...) { 
        ...
        SomeObject result = // obtain id of created node
        return result;
    }

    @Override
    public void modifyNode(SomeObject id, ...) { 
        ...
        // use id as (SomeObject)id
    } 
}

Btw, don't worry about autoboxing. You are using JDK >= 5 since there are @Override annotations.

Answer 2

I think you want Generic Methods.

Generic methods are methods that introduce their own type parameters. This is similar to declaring a generic type, but the type parameter's scope is limited to the method where it is declared. Static and non-static generic methods are allowed, as well as generic class constructors.

The syntax for a generic method includes a type parameter, inside angle brackets, and appears before the method's return type. For static generic methods, the type parameter section must appear before the method's return type.