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Java

Posted by Christian Lawrence
Christian Lawrence
3,941 Points

Is a Java ArrayList right to use here?

So I’m creating a text based game where you have various rooms to navigate through.

I want to have items in certain rooms that the user can find by typing ‘search’. If the room has an item (e.g. “diary”, ”apple“) it is placed into a collection. Am thing ArrayList called Items is the best for this?

Am also thinking I need a item class to store the Name, and Description of the item.

At certain stages, checks on the arrayList will need to be performed to see if it contains an item e.g. “apple”. 

if (ArrayList Items contains apple){ 
    pass 
} else {
    blocked
}

1 Answer

Ratul Sarna
Ratul Sarna
Courses Plus Student 11,618 Points

Hi,

ArrayList is a fine collection to use in this situation, since the number of items in a room will not be in thousands, I presume. If you are working with data in huge quantities, then, searching through it could become inefficient. But that does not seem to be the case here. Use the contains() method of the ArrayList class. Just implement an equals() method in your Item class.

On the other hand, you could use a HashSet instead of an ArrayList, if your room will not contain duplicate items. The contains() method in HashSet is really fast and efficient. It works in O(1) or constant time, ie. It does not have to go through the entire collection to look for an item. It knows where each item is. Check out its documentation here HashSet.

Christian Lawrence
Christian Lawrence
3,941 Points

Ok thank you this has been really helpful I will give both a try and get back to you.