2D-Tree is an implementation 2-dimensional tree for range and nearest neighbors searches.

• buildTree(List<Node<T>> nodes - builds balanced 2d-tree
• insert(T object, double x, double y) - inserts object into the tree
• insertOrUpdate(T object, double x, double y) - inserts object if it doesn't exists in the tree otherwise updates the existing object
• delete(T object) - deletes object from the tree

• findNearestNeighbour(double x, double y) - finds the nearest neighbor
• findNearestNeighbours(double x, double y, int k) - finds k nearest neighbors
• rangeSearch(double x, double y, double radius) - finds neighbors in specified range
• rangeSearchKm(double x, double y, double radius) - finds neighbors in specified range assuming that x is a latitude, y - longitude, radius - radius in km.