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What is a Code Kata?

A hands-on programming exercise which helps hone your skills through practice.
Code Katas are usually set up as a series of unit tests which fail. Your task is to make them pass.

I hear and I forget. I see and I remember. I do and I understand. -- Confucius</center>

Java Lambda Kata - Practice and learn Java 8 lambdas with simple exercises
Deck of Cards Kata - Practice using Java 8 Streams, Eclipse Collections, Guava, Apache Commons and/or Vavr on a simple domain
Donut Kata - Practice and learn more advanced Eclipse Collections APIs using Java or Kotlin
Calendar Kata - Practice and learn the APIs in the Java 8 Date/Time and ThreeTen-Extra libraries.
CodePoint Kata - Read a secret message from a file into memory, translate it and then write out the revealed message to a file.
JMH Kata - Experiment with the Java Microbenchmark Harness by running and writing micro-benchmark performance comparisons.
Pitest Mutation Kata - Practice and learn how to improve the quality of your tests by hunting mutants.
Kata of Katas - Practice and learn advanced methods in Eclipse Collections.
Coffee Shop Kata - Practice and learn the latest Java features while comparing them with the older ones.

Eclipse Collections Katas - Practice and learn Eclipse Collections Data Structures and Algorithms with seven code katas