Bitmap which supports indexing with long arguments. java.util.BitSet
provides all the functionality and performance we need, but requires integer
Long indexing is implemented by keeping a Map of java.util.BitSets, where
each bitset covers 2^16 bits worth of values. The Bitmap may be sparse, in
that each segment is only instantiated when needed.
Note that this class is currently not thread safe; adding a new bitset
segment is not protected.
public void set(long index)
(index + " is out of bounds");
public boolean get(long index)