Although I have Java in the title, this could be for any OO language. I'd like to know a few new ideas to improve the performance of something I'm trying to do.

I have a method that is constantly receiving an Object[] array. I need to split the Objects in this array through multiple arrays (List or something), so that I have an independent list for each column of all arrays the method receives.

Example:

List<List<Object>> column-oriented = new ArrayList<ArrayList<Object>>();

public void newObject(Object[] obj) {
    for(int i = 0; i < obj.length; i++) {
        column-oriented.get(i).add(obj[i]);
    }
}

Note: For simplicity I've omitted the initialization of objects and stuff.

The code I've shown above is slow of course. I've already tried a few other things, but would like to hear some new ideas.

How would you do this knowing it's very performance sensitive?