how can i get the word sequence of a concatenated words by java?

Question

I want to get the word sequence of a combining words, like a variable name - "NullPointException".

I want to get the "Null","point","Exception" by java.

So, Are there any open source libraries for java that I can use? Or what such tasks are called so I can search again.

I know that lingpipe can split a sentence, but is this a task it can accomplish?

or how can i do this by java? I know the python lib “wordninja”