JavaStructures is a project mainly written in Java, it's free.
Some uncommon data structures, written in Java
JavaStructures provides some basic (and probably naive) implementations of simple or useful data structures in Java. Notably, the structures here are not commonly available elsewhere, even in Apache Commons - otherwise, we would just use Apache Commons.
com.lithium3141.javastructures.trie): a basic prefix trie, generic in both key and value.Unit tests, such as they are, are kept in the package com.lithium3141.javastructures.test.