nullify object that is part of ArrayList java

Question

I have an array list:

private ArrayList<PerfStatBean> statFilterResults;

I want to iterate through it like:

Iterator<PerfStatBean> statsIterator = statFilterResults.iterator();
while(statsIterator.hasNext()){
  i++;
  PerfStatBean perfBean = statsIterator.next();
  .........

I would like to delete the bean from statFilterResults after I run through it inside the while loop to free up memory. I believe if I do something like

 perfBean = null;

it won't do the job as the perfBean reference will be null but the object will still be in memory.

Any ideas?

Thanks,

Tam

Answer 1

This probably isn't a great optimisation. If the memory requirements are large, then you probably don't want to store them all in a list in the first place - process the objects as they are created.

However, taking the question literally, ListIterator.set is the method for you.

for (
    ListIterator<PerfStatBean> iter = statFilterResults.listIterator();
    iter.hasNext()
) {
    ++i;
    PerfStatBean perfBean = iter.next();
    iter.set(null);
    ...
}