How to return a slice in Java

Question

I am working on a JavaCard, so a SIM card that runs Java (or a subset of it: Java Embedded). Due to memory limitations I have an array that I reuse for multiple tasks.

I want a function to basically return a pointer to that array, with an offset, thus a slice. This way I can be sure that no part of that array will be overwritten by accident.

Pointers dont exactly exist in Java, but is there a way to return a part of an array without copying it?

Answer 1

No, this is not possible. Object (references) is the closest you can get to pointers in Java.

If this were regular Java, I would have suggested, to wrap the array in a List with Arrays.asList and then use the List method subList, which provides a view of a section of the list without copying its contents.

However If I read the JavaCard API reference correctly these aren't included. You could try write a simple version of those interfaces/classes/methods yourself.