Presented at Reversim Summit 2015 http://summit2015.reversim.com/proposal/sk42ziAvy47MGBrLF

1. Confessions of a
Java developer
that fell in love with the
Groovy language
Victor Trakhtenberg
victortr75@gmail.com @victortr75

2. Personal
My name is Victor

3. Personal
Java.IL community co-founder
http://www.meetup.com/JavaIL/

4. Personal
Full Stack Engineer @
http://commercesciences.com/jobs

9. It is NOT an introduction to Groovy
It is NOT “why you should not use
Java”
It is NOT “why you must
use
Groovy”

10. It is “why every Java
developer
MUST KNOW
Groovy”

11. Groovy is very easy to enter
into for Java developers,
since…
Java code is Groovy code

12. Groovy Features
• Strings
• Collections
• Date
• Parsing and producing
JSON
• Working with a DB
• Processing XML
• Template engines
• Builders
• Grapes
• Traits
• Processing
configuration
• HTTPBuilder
• and many more…

13. Groovy is more than just
a set of features,
it is more than a better
Java

14. There are new concepts for
Java developers
• Dynamic language
• with optional static-typing and static-
compilation
• Closures
• Functional programming
• Meta-programming
• Mixins
• DSLs
• and more…

16. Using Groovy
Raise your hands
Using Java
Using Ruby,Python, Scala etc.

17. Prelude - REPL

18. Groovy Collections

20. Map with default

21. http://groovy-the-superb-homeless.mally.pl/

23. Using Groovy in a running Java
project
Our setup: Java Play! Framework project
Choose one concern to use Groovy
Our choice: JSON manipulations

24. Parse JSON

25. Build JSON

26. Case Study: Campaign Configuration
Management

27. The Java interface and
the Groovy implementation

28. Java-to-Groovy Bridge

29. Fetch campaign type

30. Is it a ‘coupon’ campaign

31. Is it a ‘coupon’ campaign

32. Is it a ‘coupon’ campaign

33. http://groovy.codehaus.org/modules/http-builder/home.html
Integrate with Salesforce

34. Update account at Salesforce

35. Integrate with Salesforce - Authenticate

36. URIBuilder

37. URIBuilder - Java

38. Challenges
• IDE support
– Browsing Java code – Groovy code
• Long stack traces
– challenging debugging
• Coding conventions

39. Use Groovy for non-production

40. Groovy in light of Java8
• There is still a gap between Java 8 and Groovy
• There is a synergy between Groovy and Java 8
http://www.slideshare.net/SpringCentral/groovy-in-thelightofjava8
http://www.javacodegeeks.com/2014/06/java-8-lambdas-vs-groovy-closures-compactness-grouping-and-summing.html

41. http://jaxenter.com/groovy-is-the-swift-alternative-for-android-107846.html

43. Groovy resources
• http://groovy-lang.org/
• http://glaforge.appspot.com/category/Groovy%20Weekly
• http://www.mrhaki.com/
• https://plus.google.com/communities/105160926044623621768
• http://www.mscharhag.com/2015/02/creating-android-apps-with-
groovy.html
• http://groovy.codehaus.org/modules/http-builder/doc/uribuilder.html
• http://www.drdobbs.com/jvm/why-build-your-java-projects-with-
gradle/240168608?pgno=3
• http://www.infoq.com/presentations/groovy-test-java-spock
• http://www.infoq.com/presentations/testing-spock-geb
• http://melix.github.io/blog/2015/02/who-is-groovy.html
• http://groovy-the-superb-homeless.mally.pl/#/
• http://www.eweek.com/developer/groovy-language-proposed-as-
apache-incubator-project.html
• https://github.com/victorgit/GroovyPresentation

44. MrHaki – Groovy Goodness
http://mrhaki.blogspot.co.il/2009/09/groovy-goodness-padding-strings.html

46. Images sources
• http://www.clevercuties.com/myimages/products/Computers/IHEARTPROGRAMMING.jpg
• http://blogs.perceptionsystem.com/wp-content/uploads/2013/12/Happy-Customer.jpg
• http://lifepalette.com/wp-content/uploads/2015/01/Productivity.jpg
• http://www.checkaction.com/blog/wp-content/uploads/2014/01/startup-employee-productivity-tips-675x320.jpg
• http://www.akifarslan.com.tr/wp-content/uploads/2013/10/java.jpg
• http://cdn.makeuseof.com/wp-content/uploads/2012/03/jvm.png?84ec63
• http://cdn.slidesharecdn.com/ss_thumbnails/ecosystem-120717081103-phpapp01-thumbnail-
4.jpg?cb=1342530724
• http://www.army-armee.forces.gc.ca/assets/ARMY_Internet/images/ceremonial-guard/index-main.jpg
• http://www.local-guru.net/img/guru/have_fun.png
• http://blog.xo.com/wp-content/uploads/2014/03/pic-raised-hands-550x300.png
• https://pbs.twimg.com/media/BVDKBfUCIAAWKw9.jpg
• http://www.nscsd.org/webpages/jenkondrk/imageGallery/Clip%20art/raise%20hand.gif
• http://ubik.cc/MAOW-Firenze-09/images/repl-loop.png
• http://hirportal.sikerado.hu/images/kep/201110/belyeg.jpg
• http://www.slideshare.net/SpringCentral/groovy-in-thelightofjava8
• http://blog.pivotal.io/pivotal/news-2/groovy-2-4-and-grails-3-0-to-be-last-major-releases-under-pivotal-
sponsorship
• http://therealdanvega.com/blog/2015/01/20/pivotal-drops-groovy-grails-sponsorship
• http://grails.io/post/108534902333/the-future-of-groovy-grails-sponsorship
• http://groovy.mn/static/hh97hMrFEv8Xc9j1zvR9winGH86xmHGbiZNKFTORWYl.jpg