At work, Oracle provided us some unit test training with C# and NUnit by Gerard Meszaros. One of the hands on exercises was the To Roman Numeral kata. My original C# implementation was pretty convoluted, so I thought I'd redo it in Java:
RomanNumeralConverterPlaceValue.java
I've been wanting to try the JMH microbenchmarking framework so I added an optimized version to compare:
RomanNumeralConverterPlaceValueOptimized.java
Lastly, I liked this article Informed TDD – Kata “To Roman Numerals” so I ported that implementation to Java to see how it could be done in Java 8:
RomanNumeralConverterJava8Streams.java
The benchmark code is under: src/jmh and is built with the jmh-gradle-plugin.