How to get the nearest neighbor in weka using java

I've been trying to use开发者_运维知识库 the Ibk nearest neighbor algorithm that goes together with the weka machine learning library.

I know how to classify instances, but I want to implement the collaborative filtering feature so I need to actually get the list of actual objects that are nearest to the object of interest.

How would I actually do so in weka using its java API?

How about this one

weka.core.neighboursearch.LinearNNSearch knn = new LinearNNSearch(
            trainingInstances);
//do other stuff

Instances nearestInstances= knn.kNearestNeighbours(target, 3)

Here is the API documentation that you can refer to.