This is a my mower implementation (I hope it will not scratch too much your eyes :).
I chose an Engine-based architecture after considering Subject(Mower) / Observer(Lawn) pattern.

Assuming two mowers can't be at the same position (ambiguous requirement), the mower don't move if a collision with another mower is detected.

• JDK 1.6
• Maven 3
• SLF4J + LogBack
• TestNG
• FestAsserts
• JBehave

mvn clean package
cd target
java -jar mower-<version>.jar src/test/resources/commands.txt

Note: the package lifecycle build a shaded (i.e standalone) jar with all dependencies.

mvn clean verify

You can view JBehave reports at:

• target/jbehave/view/index.html
• target/jbehave/view/reports.html

Feel free to write your own scenarios in the file app_scenarios.story

A mower-<version>-sources.jar and mower-<version>-javadoc.jar are generated at package lifecycle.
You can use them with your favorite IDE.

Continuous integration provided by Travis CI

• 675 lines
• 99,1 rules compliances (2 violations)
• 84,3 units tests coverages
• 0% duplications / pti
• 100% tests success