I was checking out this post (Representing a 100K X 100K matrix in Java) and implemented the solution regarding Maps and floats. However, the heap still runs out of memory if I fill the map with every entry in a 100K by 100K matrix. Is there a better solution without having to resort to 3rd party solutions (and also besides just increasing the heap allocation)?

I would like to implement this for a graph, by the way. I work with huge graphs.