How do I take an Iterable of one class and turn it into an Iterable of another class?

Question

I have an iterable of one class: Iterable<ClassA> classAIterable . I have a second class like this:

public class ClassB {
    private final ClassA classA;
    public ClassB(ClassA a) {
        this.classA = a;
    }
}

I would like to take every ClassA object in classAIterable and turn it into a ClassB object that contains a ClassA object and put them into an iterable of ClassB .

How would I do this? Thanks!

Answer 1

You can convert your Iterable to a Stream by accessing the Spliterator , by using StreamSupport.stream . In the Stream you can map the elements from ClassA to ClassB , then collect them into a List , which is Iterable .

Iterable<ClassB> iterB = StreamSupport.stream(iterable.spliterator(), false)
    .map(ClassB::new)
    .collect(Collectors.toList());

Answer 2

Of course it might not be suitable in your case, but as a variant of solution:

1) U can create interface:

interface interfaceC {
    }

2) And implement it in both ClassA and ClassB :

class ClassA implements interfaceC {        
    }

class ClassB implements interfaceC {        
    }

3) And then use iterable of interfaceC

class classIterable implements Iterable<interfaceC> {
        private List<interfaceC> internalList = null;
    }

Might work for u