For what it's worth, you might want to take OptaPlanner for a spin too (another open source constraint solver in Java). Although it's focuses more on the vehicle routing problem, employee rostering, bin packing, etc than soduko and graph coloring.
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For what it's worth, you might want to take OptaPlanner for a spin too (another open source constraint solver in Java). Although it's focuses more on the vehicle routing problem, employee rostering, bin packing, etc than soduko and graph coloring.