A diamond for a letter!

Given a single letter, print a diamond starting with "A" with the supplied letter at the widest point.

Example for "A":

A

Example for "B":

 A
B B
 A

Example for "C":

  A
 B B
C   C
 B B
  A

Use the Diamond program in command line as following.

mvn clean package -Pstandalone # to build it once
java -jar target/diamond-kata-standalone.jar F # to run it as many times as you want

You will get this result.

     A
    B B
   C   C
  D     D
 E       E
F         F
 E       E
  D     D
   C   C
    B B
     A

The Diamond program works for uppercase letters as for lowercase letters. For example, the diamond printed for "c":

  a
 b b
c   c
 b b
  a

Also use it as a Java library with Maven.

<dependency>
    <groupId>com.xavierpigeon</groupId>
    <artifactId>diamond-kata</artifactId>
    <version>0.1.0-SNAPSHOT</version>
</dependency>

And get any diamond you want like that.

import kata.Diamond;

class Example {
    public static void main(String[] args) {
        String diamond = Diamond.of("X");
    }
}

Use the below badge if you use TestAsYouThink Core to write high-quality tests.

Firstly, either you fork this repository to put all your katas in the same repository, either you create a new repository per kata and push the kata boilerplate into it. Then replace the artifact coordinates used by the build system. Name the code kata too.
Make changes only in the "kata" branch.
You can use this shortened link if needed: tinyurl.com/yyekn5rf.

You may want to commit with another identifier to publish your code later. Nothing"s easier:

git config user.email "[email protected]"
git config user.name "Your Pseudo" # if needed

Take advantage of your IDE shortcuts while resolving any code kata. Download and print the keymap of IntelliJ IDEA. The table below should be very useful to learn, or to learn again, the most important shortcuts.

If a shortcut is marked with a "*", it is to configure in the keymap settings of the IDE.

You can invoke a standalone JAR after building it with the "standalone" Maven profile.

mvn package -Pstandalone # to build it
java -jar target/kata-standalone.jar # to use it

Update your fork as follows. It is assumed you did not commit in the "master" branch. Otherwise please send me a pull request.

git fetch origin master && git rebase -p --onto origin/master master develop && git branch -f master origin/master

What should be a DoD for the code katas?

• The kata is done by applying Test-Driven Development (TDD).
• The code is versioned by applying TDDflow.
• The path to the solution is discovered according to the Transformation Priority Premise.
• The path of successive transformations is as simple as possible.
• The code coverage is greater than 95%.
• The problem to solve is described in the kata documentation.

This code kata boilerplate is distributed under the GNU GPLv3 license. The GPLv3 license is included in the LICENSE.txt file. More information about this license is available at GNU.org.