2014_GHC_Groovy_Gr8Ladies_Workshop_v16.pdf

Transcript

1. 2014 Groovy & Gr8Ladies Jenn Strater & Allison F October 10, 2014 @gr8ladies #GHC14 2014
2. 2014 Who are We? §  Jenn Strater −  Software Engineer at Altegra Health −  Gr8Ladies Co-Founder •  Focus on retention and professional development §  Allison Figus −  Software Engineer at Bloom Health −  Gr8Ladies Co-Founder •  Focus on education and career changes
3. 2014 Setup §  http://bit.ly/graceHopperSetup §  https://groovyconsole.appspot.com/
4. 2014 Gr8Ladies §  Organization for the support of women in the Gr8 (Groovy, Grails, Gradle, etc) community −  Education −  Professional Development −  Networking −  Retention
5. 2014 What’s Groovy §  Groovy is a dynamic compiled language for the Java Virtual Machine (JVM). §  Interoperable with existing Java Libraries §  Used by many major companies including:
6. 2014 Groovy Console §  In the shell, type groovyConsole then type enter to execute the console.
7. 2014 Groovy Console Commands §  Mac: −  Cmd-R to run the script −  Select text and press delete to clear the white input box −  Cmd-W to clear the yellow output box §  Windows: −  Ctrl-R to run the script −  Select text and press delete to clear the white input box −  Ctrl-W to clear the yellow output box
8. 2014 Hello, Grace! §  In Java: public class Main {! public static void main(String[] arguments) {! System.out.println(“Hello, Grace!”);! }! }! à Hello, Grace! §  In Groovy: println “Hello, Grace!”! à Hello, Grace!! Try It!
9. 2014 Data types §  Strings §  Collections −  Lists −  Maps §  Closures §  def
10. 2014 Strings §  Single Quoted println 'Hello, World!’! à Hello, World!! §  Double Quoted (Groovy String) String name = ‘Gr8Ladies’! println "Hello, $name”! à Hello, Gr8Ladies!! §  Multi-line '''Hello, everyone from ! The Grace Hopper! Celebration of Women! in Computing 2014!'''!
11. 2014 String Manipulation §  Split String s = ‘I <3 Groovy’! s.tokenize(‘ <3 ’)! à [‘I’, ‘Groovy’]! §  Join List los = [‘I' , ‘<3’, ‘Groovy’]! los.join(‘ ‘)! à I <3 Groovy! Try It! Try It!
12. 2014 Collections
13. 2014 Lists §  Definition List l = [‘a’,’b’,2]! §  Access: []! l[2] = 3! à  [a, b, 3]! §  Shovel operator: << l << 5! à [a, b, 3, 5]! •  Multiply l.multiply(2)! à [a, b, 3, 5, a, b, 3, 5]!
14. 2014 §  Example List l = [‘a’, ‘b’, 2]! l[2] = 3! l << 5! l.multiply(2)! à [a, b, 3, 5, a, b, 3, 5]! Try It!
15. 2014 Maps §  Definition Map m = [val1: ‘a’, val2: ‘b’, val3: 2]! à[val1: a, val2: b, val3: 2]! §  Access −  by key m.val1! à a! m.val4 = 5! à [val1: a, val2: b, val3: 2, val4: 5] −  all values m.values()! à [a, b, 2, 5]!
16. 2014 §  Example Map m = [val1: ‘a’, val2: ‘b’, val3: 2]! m.val2 = ‘c’! m.val4 = 5! m.values()! à [a, c, 2, 5]! Try It!
17. 2014 Functions
18. 2014 Functions §  Extremely flexible, but familiar syntax §  Optional −  parenthesis around parameters when calling functions −  parameter typing −  return statements §  Example int foo (x) {! !x * 2! }! foo(4)! à  8! foo 5! à  10! int! foo! ( int! x )! return type! function name! parameter type! parameter name!
19. 2014 §  Example int foo(int x) {! x * 5! }! foo 6! à 30! Try It!
20. 2014 Closures §  Closures are code as data. §  Definition Closure myClosure = { name, int year = 2014 ->! println "Welcome to $name $year"! }! § Usage myClosure.call('Grace Hopper')! à Welcome to Grace Hopper 2014
21. 2014 §  Example def c = { name, int year = 2014 ->! println "Welcome to $name $year"! }! c.call('Grace Hopper')! à Welcome to Grace Hopper 2014 ! Try It!
22. 2014 Loops and Special Functions §  Definition −  Repeat the same functionality §  Basic For Loop §  Each §  Collect §  Spread Dot
23. 2014 Basic Loops §  Groovy List doubledList = []! for (i in [2, 4, 6]) {! doubledList << i * 2! }! à doubledList == [4, 8, 12]! §  Java! int[] myList = {2, 4, 6};! int[] doubledList = new int[3];! for (int i = 0; i < 3; i++) {! doubledList[i] = myList[i] * 2;! }! à  doubledList == [4, 8, 12]!
24. 2014 Each §  Example! Map m = [val1: 2, val2: 4, val3: 6]! List dl = []! m.each { key, value ->! dl << value * 2! }! println dl! à [4, 8, 12]! §  Loop equivalence Map myNewMap = [val1: 2, val2: 4, val3: 6]! List myDoubledList = []! for (keyValuePair in myNewMap) {! myDoubledList << keyValuePair.value * 2! }! println myDoubledList! à [4, 8, 12]! Try It!
25. 2014 Collect §  Example! Map m = [var1: 2, var2: 4, var3: 6]! List dl = m.collect { name, value ->! !value * 2! }! println dl! à [4, 8, 12]! §  Loop equivalence Map myNewMap = [val1: 2, val2: 4, val3: 6]! List myDoubledList = []! for (keyValuePair in myNewMap) {! myDoubledList << keyValuePair.value * 2! }! println myDoubledList! à [4, 8, 12]! Try It!
26. 2014 Spread Dot *. §  Example List l = [2, 4, 6]! l*.multiply(2)! à  [4, 8, 12]! §  Loop Equivalence List myList = [2, 4, 6]! List doubledList = []! for (value in myList) {! doubledList << value * 2! }! doubledList! à [4, 8, 12]! Try It!
27. 2014 §  Convert this loop to use *. List l = [-1, 2, -3, -17]! List al = []! for (i in l) {! al << i.abs()! }! al! à [1, 2, 3, 17] ! Try It!
28. 2014 Spread Dot Exercise §  Answer List al = [-1, 2, -3, -17]*.abs()! à  [1, 2, 3, 17]! Or! List l = [-1, 2, -3, -17]! List al = l*.abs()! à [1, 2, 3, 17] !
29. 2014 §  Sum the numbers from 1 to 10 Try It!
30. 2014 Possible Solutions 1.  for in List! int answer = 0 ! for (i in [1,2,3,4,5,6,7,8,9,10]) {! !answer += i! }! println answer! à 55! 2.  Each! int answer = 0! [1, 2, 3, 4, 5, 6, 7, 8, 9, 10].each {! answer = answer + it! }! println answer! à 55! 3.  Sum Function (Bonus)! int answer = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10].sum()!
31. 2014 Search Map m = [var1: 2, var2: 4, var3: 6]! §  find m.find{ it.value%2 == 0 && it.value%3 !=0 }! à var1:2! §  findAll m.findAll{ it.value%2 == 0 && it.value%3 !=0 }! à[var1:2, var2:4]! Try It! Try It!
32. 2014 Questions?
33. 2014 Resources §  Groovy Documentation −  http://groovy-lang.org/documentation.html §  Groovy Communities −  Gr8Ladies •  http://gr8ladies.org •  http://forum.gr8ladies.org −  Local User Groups •  http://groovy-lang.org/usergroups.html
34. 2014 Got Feedback? Rate and Review the session using the GHC Mobile App To download visit www.gracehopper.org