Java code challenge

This challenge is meant to measure your fundamentals. Please complete the solutions in Java. The
code should compile and execute without modification, or dependency download, or machine specific
settings. It is also required that you write out the tests. The minimal test set should include a test
function, accepting the incoming data, and printing out the incoming data and the result for a
developer to see in the console. Please do not input data from console or file, all the input should be
provided in the test code