java.il - confessions of a java developer that fell in love with the groovy language

Confessions  of  a    Java  developer    

that  fell  in  love  with  the  Groovy  language  

Victor  Trakhtenberg    

victortr75@gmail.com              @victortr75            

Personal  

My  name  is  Victor  

Personal  

Java.IL  community  co-­‐founder  

h=p://www.meetup.com/JavaIL/  

Personal  

Full  Stack  Engineer  @    

h@p://commercesciences.com/jobs  

It  is  NOT  an  introducFon  to  Groovy  

It  is  NOT  “why  you  should  not  use  Java”  

It  is  NOT  “why  you  must    use    

Groovy”  

It  is  “why  every  Java  developer    

SHOULD  KNOW    Groovy”  

Groovy  is  very  easy  to  enter  into  for  Java  developers,  

since…  

Java  code  is  Groovy  code  

Groovy  Features  

•  Strings  •  CollecFons  •  Date  •  Parsing  and  producing  JSON  

•  Working  with  a  DB  •  Processing  XML  •  Template  engines  

•  Builders  •  Grapes  •  Traits  •  Processing  configuraFon  

•  HTTPBuilder  •  and  many  more…  

Groovy  is  more  than  just  a  set  of  features,  

it  is  more  than  a  be=er  Java  

There  are  new  concepts  for  Java  developers  

•  Dynamic  language  •  with  opFonal  staFc-­‐typing  and  staFc-­‐compilaFon  

•  Closures  •  FuncFonal  programming  •  Meta-­‐programming  •  Traits  •  DSLs    •  and  more…  

Using  Groovy  

Raise  your  hands  

Using  Java  

Using  Ruby,Python,  Scala  etc.  

Prelude  -­‐  REPL  

Groovy  CollecFons  

Map  with  default  

h=p://groovy-­‐the-­‐superb-­‐homeless.mally.pl/  

Using  Groovy  in  a  running  Java  project  

Our  setup:  Java  Play!  Framework  project  

Choose  one  concern  to  use  Groovy  

Our  choice:  JSON  manipulaFons  

Parse  JSON  

Build  JSON  

Case  Study:  Campaign  ConfiguraFon    Management  

The  Java  interface  and    the  Groovy  implementaFon  

Java-­‐to-­‐Groovy  Bridge  

Fetch  campaign  type  

Is  it  a  ‘coupon’  campaign  

Is  it  a  ‘coupon’  campaign  

Is  it  a  ‘coupon’  campaign  

Integrate  with  Salesforce    

Update  account  at  Salesforce  

Integrate  with  Salesforce  -­‐  AuthenFcate  

URIBuilder  

URIBuilder  -­‐  Java  

Challenges  

•  Java  <-­‐>  Groovy  bridge  – The  need  for  the  Java  interface  

•  IDE  support  – Browsing  Java  code  –  Groovy  code  

•  Long  stack  traces    –   challenging  debugging  

•  Coding  convenFons  

Use  Groovy  for  non-­‐producFon  

Groovy  in  light  of  Java8  

•  There  is  sFll  a  gap  between  Java  8  and  Groovy  •  There  is  a  synergy  between  Groovy  and  Java  8  

h=p://www.slideshare.net/SpringCentral/groovy-­‐in-­‐thelightoaava8  h=p://www.javacodegeeks.com/2014/06/java-­‐8-­‐lambdas-­‐vs-­‐groovy-­‐closures-­‐compactness-­‐grouping-­‐and-­‐summing.html  

Groovy  in  light  of  Java8  •  Groovy  syntax  is  more  compact  •  JDK  classes  enhancements  (String,  URL,  File  etc.)  •  Operator  overloading  •  MemoizaFon  +  trampoliningRegular  expressions  •  SQL  handling  •  Coercion  of  types  to  Boolean  •  JSN  +  XML  parsing  and  producing  •  Traits  •  AST  transformaFons  •  DSL  •  …  

h=p://jaxenter.com/groovy-­‐is-­‐the-­‐swin-­‐alternaFve-­‐for-­‐android-­‐107846.html  

Groovy  resources  •  h=p://groovy-­‐lang.org/  •  h=p://glaforge.appspot.com/category/Groovy%20Weekly  •  h=p://www.mrhaki.com/  •  h=ps://plus.google.com/communiFes/105160926044623621768  •  h=p://www.mscharhag.com/2015/02/creaFng-­‐android-­‐apps-­‐with-­‐

groovy.html  •  h=p://groovy.codehaus.org/modules/h=p-­‐builder/doc/uribuilder.html  •  h=p://www.drdobbs.com/jvm/why-­‐build-­‐your-­‐java-­‐projects-­‐with-­‐

gradle/240168608?pgno=3  •  h=p://www.infoq.com/presentaFons/groovy-­‐test-­‐java-­‐spock  •  h=p://www.infoq.com/presentaFons/tesFng-­‐spock-­‐geb  •  h=p://melix.github.io/blog/2015/02/who-­‐is-­‐groovy.html  •  h=p://groovy-­‐the-­‐superb-­‐homeless.mally.pl/#/  •  h=ps://github.com/victorgit/GroovyPresentaFon  

MrHaki  –  Groovy  Goodness  

h=p://mrhaki.blogspot.co.il/2009/09/groovy-­‐goodness-­‐padding-­‐strings.html  

Groovy  Challenge!    

Save  the  date:  31-­‐May  

h=p://www.meetup.com/WeCode-­‐IL/  

Images  sources  •  h=p://www.clevercuFes.com/myimages/products/Computers/IHEARTPROGRAMMING.jpg  •  h=p://blogs.percepFonsystem.com/wp-­‐content/uploads/2013/12/Happy-­‐Customer.jpg  •  h=p://lifepale=e.com/wp-­‐content/uploads/2015/01/ProducFvity.jpg  •  h=p://www.checkacFon.com/blog/wp-­‐content/uploads/2014/01/startup-­‐employee-­‐producFvity-­‐Fps-­‐675x320.jpg  •  h=p://www.akifarslan.com.tr/wp-­‐content/uploads/2013/10/java.jpg  •  h=p://cdn.makeuseof.com/wp-­‐content/uploads/2012/03/jvm.png?84ec63  •  h=p://cdn.slidesharecdn.com/ss_thumbnails/ecosystem-­‐120717081103-­‐phpapp01-­‐thumbnail-­‐4.jpg?cb=1342530724  •  h=p://www.army-­‐armee.forces.gc.ca/assets/ARMY_Internet/images/ceremonial-­‐guard/index-­‐main.jpg  •  h=p://www.local-­‐guru.net/img/guru/have_fun.png  •  h=p://blog.xo.com/wp-­‐content/uploads/2014/03/pic-­‐raised-­‐hands-­‐550x300.png  •  h=ps://pbs.twimg.com/media/BVDKBfUCIAAWKw9.jpg  •  h=p://www.nscsd.org/webpages/jenkondrk/imageGallery/Clip%20art/raise%20hand.gif  •  h=p://ubik.cc/MAOW-­‐Firenze-­‐09/images/repl-­‐loop.png  •  h=p://hirportal.sikerado.hu/images/kep/201110/belyeg.jpg  •  h=p://www.slideshare.net/SpringCentral/groovy-­‐in-­‐thelightoaava8  •  h=p://blog.cacoethes.co.uk/groovyandgrails/groovy-­‐in-­‐light-­‐of-­‐java-­‐8  •  h=p://www.infoq.com/arFcles/groovy-­‐to-­‐Java-­‐8  •  h=ps://tedvinke.wordpress.com/2014/06/20/java-­‐8-­‐lambdas-­‐vs-­‐groovy-­‐closures-­‐compactness-­‐grouping-­‐and-­‐summing/  •  h=p://groovy.mn/staFc/hh97hMrFEv8Xc9j1zvR9winGH86xmHGbiZNKFTORWYl.jpg