Refactor IntervalPrice?

[Richard Gomes]

This issue is in complement to issue 515
http://bugs.jquantlib.org/view.php?id=515

In some cases, we have TimeSeries<IntervalPrice>, which would mean:
  class TimeSeries<IntervalPrice> extends Series<Long,IntervalPrice>

Notice that IntervalPrice has the following internal fields:
    private double open;
    private double close;
    private double high;
    private double low;

In this way, it would be better, from performance of view, to have TimeSeries (or Series, to be more precise) simply as a Decorator which aggregates structures backed on primitive types (fastutil), delegating calls as necessary to underlying objects.

So, one idea would be maintaining internal Maps like this:
    Map<Long,Double> open;
    Map<Long,Double> close;
    Map<Long,Double> high;
    Map<Long,Double> low;

It's not clear at this point if it would be viable to refactor IntervalPrice.

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Relationships
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related to http://bugs.launchpad.net/bugs/jquantlib-515