java: sparse bit vector

Question

Are there any well-known libraries in Java for sparse bit vectors?

(And are there guidelines for how sparse is useful to use them vs. java.util.BitSet?)

Answer 1

CERN COLT is widely used for vector and matrix computation, and has sparse matrices, but isn't specifically used for bit vectors.

http://acs.lbl.gov/software/colt/api/cern/colt/matrix/impl/SparseObjectMatrix1D.html