Spring mvc: what is the params separator

I was wondering what the seperator is for params (@ActionMapping(params ="...");)

I'd like to place a back button inside a form which already has a next button, and I've read in the docs that I can do: myParam!=myValue to ignore things so I would like to do sonething like:

@ActionMapping(params="myAction=registerUser**SEPARATOR**nextParam!=previous"){}

@ActionMapping(开发者_如何学Pythonparams="nextParam=previous"){}

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params is an array:

@ActionMapping(params = {"myAction=registerUser", "nextParam!=previous"})