refact: improve handling of arrays

[sebthom]

This PR improves working with arrays, by avoiding unnecessary temporary array allocations and providing specialized functions for filtering/iterating arrays which improves readability and avoids duplicate code.

[sebthom]

@rubenporras I did not want to name the empty arrays as verbose as EMPTY_BYTE_ARRAY so I went with ZERO_BYTES but would I actually prefer to name them even shorter like NO_BYTES, NO_OBJECTS but I am unsure if this could result in misunderstandings when reading the code. WDYT?

[rubenporras]

@rubenporras I did not want to name the empty arrays as verbose as EMPTY_BYTE_ARRAY so I went with ZERO_BYTES but would I actually prefer to name them even shorter like NO_BYTES, NO_OBJECTS but I am unsure if this could result in misunderstandings when reading the code. WDYT?

I think that if you know that it is beneficial to reuse empty arrays to reduce creation/garbage collection, all names are fine, and otherwise you will not understand it.

What about choosing the names you like and commenting the class ArrayUtil with the explanation of the pattern?