Learning Java Help please!

[Speckydodge]

Hi im learning java through blue j and im having trouble doing an exercise if anyone can help that would be great.
the question is:

Rewrite the getLot method so it doesn't rely on a lot with a particular number being stored at index (number -1) in the collection.You may assume that lots are always stored in increasing order of their lot number.

The method is written ass :

public Lot getLot(int lotNumber)
    {
        if((lotNumber >= 1) && (lotNumber < nextLotNumber)) {
            // The number seems to be reasonable.
            Lot selectedLot = lots.get(lotNumber - 1);
            // Include a confidence check to be sure we have the
            // right lot.
            if(selectedLot.getNumber() != lotNumber) {
                System.out.println("Internal error: Lot number " +
                                   selectedLot.getNumber() +
                                   " was returned instead of " +
                                   lotNumber);
                // Don't return an invalid lot.
                selectedLot = null;
            }
            return selectedLot;
        }
        else {
            System.out.println("Lot number: " + lotNumber +
                               " does not exist.");
            return null;
        }
 
 

Any help would be much appreciated again

[JosAH]

Would a Map<Integer, Lot> be of help? The Integer is the lot number, stored as the key in the Map, the associated value is the Lot itself.

kind regards,

Jos

[Speckydodge]

maybe but i havent come across maps yet...im just a wee beginner ha :)

thanks for the help though bud.

[JosAH]

@Speckydodge
Well, then you're stuck with your arrays then. The index number of the array has a functional dependency on the Lot number. There's no way to get rid of it.

kind regards,

Jos