我怎样才能在SPARK中用MLlib训练模型，并使用字符串数据帧值？

I am new on Apache SPARK and MLlib and I am trying to build a model to make a supervised classification over a dataset. The problema that I have is that all the examples I found in the internet are explanations of how to work with REGRESSION problems, and always with numerical values. But I have the next context:I am new on Apache SPARK and MLlib and I am try