Perfomance Testing for a one class java application [duplicate]

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• How do I write a correct micro-benchmark in Java? 11 answers

I need to run perfomance testing for a simple java class which does some simple file read and write. I am new to perfomance testing and all the tools I am seeing are for web application. Which tool should I use.

My program has four methords doing same purpose and written in different logic I want to find which of the methord is more efficient