Feb 24 2018
CompactList implements the
List<Long> interface, but internally it uses a tree of variable word-width segments to
improve performance and memory usage compared to an
Performance tends to be worse for appends than an
ArrayList but better for inserts. Memory usage is significantly
reduced, even for incompressible random data where it approaches the memory use of an array of primitive longs (which
happens to be the internal representation in this case).