I had no problem accessing the class reference at the link you provided. Your reference to "this class" makes me think that the problem is actually that you're looking for a client for a particular programming language (e.g., Java). There is no official class for other languages, but there is sample code for accessing the API via the JSON (aka RESTful) interface at the link below:
Using the resources at that link, you should be able to write your own wrapper class in just about any language. If you're looking for something else, you'll have to clarify.
Jeremy R. Geerdes
Generally Cool Guy
Des Moines, IA
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