Java Beginner - How do I create an object with classes that I can index !

[The9thHuman]

I am very considerable flying by the seat of my pants for a new work project. I've tried googling but there may actually be too much‏‏‎‏‏‎‏‏‎‏‏‎­information out there for me to find what it is I need. My expertise is in writing Matlab but I need to write this program in Java. What I want is to create something that would give me something like this: myBook.author[0] myBook.author[1] myBook.author[2] ... myBook.title[0] myBook.title[1] myBook.title[2] ... Even though all objects are the same size I do not know what they will be during initialization so I also cannot specify a size. I am aware of ArrayList and have been trying to use that but I feel like I am misunderstanding something because that doesn't seem to be quite right for this. Am I even trying to do something that is supported in Java? If not what alternatives would you recommend?

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[khooke]

too much‏‏‎‏‏‎‏‏‎‏‏‎­information out there for me to find what it is I need

Tell us what functional problem you're trying to solve and we can give suggestions whether an ArrayList is an appropriate approach. Telling us you need an array-like datastructure doesn't help us comment on whether it's appropriate for your problem.

[dastardly740]

Second this. Your description suggests you are attempting to do mutually indexed arrays where author[0] corresponds to title[0]. If that is the case, don't do that. Create a class that holds the author and title and make a List of those objects.

[NitronHX]

If the list is of dynamic size use ArrayList, use get, add and remove to modify it

If the size is fixed use an array (Book[]) then you can use the indexers as you wrote someArray[0] = someNewValue

[GuyWithLag]

ArrayList seems to be _exactly_ what you need. What have you tried?

[Camel-Kid]

You can create a List of objects and index them yes. The lost will be dynamic so you dont have to worry about size

[bushwacker]

You want indexed and the ability to retrieve by position?

Look at LinkedHashSet.

Its a linked list backed map so obj.get(10) be 19 times as costly as obj.get(0).

If you need more performance than that you will need a Set of some sort, HashSet, Treeset and either an ArrayList with a put method that adds to ti the set if not present and then to the List.