Groovy as a Scripting Language

Gr8Ladies Gr8Workshop Sesion1: Groovy as a Scripting Language
June 28, 2014

Transcript

1. GROOVY AS A SCRIPTING LANGUAGE Created by / Jenn Strater @jennstrater
2. WHAT'S GROOVY? Groovy is a dynamic compiled language for the Java Virtual Machine (JVM)
4. HELLO WORLD IN JAVA: p u b l i c c l a s s M a i n { p u b l i c s t a t i c v o i d m a i n ( S t r i n g [ ] a r g u m e n t s ) { S y s t e m . o u t . p r i n t l n ( " H e l l o W o r l d ! " ) ; } } IN GROOVY: p r i n t l n " H e l l o , W o r l d ! "
5. DATA TYPES Strings Functions Collections Lists Maps
6. STRINGS Single Quotes ' H e l l o , w o r l d ! ' Double Quotes -- GString " H e l l o , $ n a m e " Multi-line Strings ' ' ' T h i s i s a m u l t i - l i n e s t r i n g ' ' '
7. STRING MANIPULATION Split d e f m y S t r i n g = ' I < 3 G r o o v y ' m y S t r i n g . t o k e n i z e ( ' < 3 ' ) - - > [ I , G r o o v y ] Join d e f m y L i s t O f S t r i n g s = [ ' I ' , ' < 3 ' , ' G r o o v y ' ] m y L i s t O f S t r i n g s . j o i n ( ' ' ) - - > I < 3 G r o o v y
8. CLOSURES d e f a = { p a r a m s - > p r i n t l n ( p a r a m s * 2 ) } [ 1 , 2 , 3 ] . e a c h a - - > 2 - - > 4 - - > 6 a ( 1 ) - - > 2
9. COLLECTIONS
10. Lists d e f m y L i s t = [ ' a ' , ' b ' , 2 ] m y L i s t . m u l t i p l y ( 2 ) - - > [ ' a ' , ' b ' , ' 2 ' , ' a ' , ' b ' , ' 2 ' ]
11. SPECIAL FUNCTIONS Spread Dot m y L i s t * . m u l t i p l y ( 2 ) - - > [ ' a a ' , ' b b ' , 4 ]
12. MAPS d e f m y M a p = [ v a l 1 : ' a ' , v a l 2 : ' b ' , v a l 3 : ' b ' ] m y M a p . v a l u e s ( ) - - > [ ' a ' , ' b ' , 2 ] m y M a p . f i n d { i t . v a l u e = = ' b ' } - - > v a l 2 = b m y M a p . f i n d A l l { i t . v a l u e = = ' b ' } - - > [ v a l 2 : b , v a l 3 : b ]
13. LOOPS
14. Each d e f m y L i s t = [ 1 , 2 , 3 ] d e f r e s u l t = [ ] m y L i s t . e a c h { r e s u l t < < i t * 2 } p r i n t l n r e s u l t - - > [ 2 , 4 , 6 ]
15. Collect d e f m y L i s t = [ 1 , 2 , 3 ] d e f r e s u l t = m y L i s t . c o l l e c t { i t e m - > i t e m . m u l t i p l y ( 2 ) } p r i n t l n r e s u l t - - > [ 2 , 4 , 6 ]
16. Ranges ( 1 . . 3 ) . e a c h { p r i n t l n i t * 2 } - - > 2 - - > 4 - - > 6
17. FILE PROCESING
18. CREATING & WRITING TO FILES d e f m y F i l e = n e w F i l e ( ' f o o . t x t ' ) m y F i l e . w r i t e ' h e l l o , w o r l d ! ! \ n ' m y F i l e . a p p e n d ( ' a n d h e l l o u n i v e r s e ! ' )
19. READING FILES d e f m y F i l e = n e w F i l e ( ' f o o . t x t ' ) m y F i l e . e a c h L i n e { l i n e - > d e f p r o c e s s e d L i n e = l i n e . r e p l a c e A l l ( ' h e l l o ' , ' h i ' ) p r i n t l n p r o c e s s e d L i n e } - - > h i , w o r l d ! - - > a n d h i u n i v e r s e !
20. THINGS TO REMEMBER Typing variables is optional Some syntax is optional semi-colons parenthesis around function parameters explicit return statements The last operation completed is the default return value There is more than one way to do almost everything!
21. EXERCISES (HANDOUT) RESOURCES http://beta.groovy-lang.org/docs/groovy- 2.3.1/html/documentation/#_introduction http://beta.groovy-lang.org/docs/latest/html/groovy-jdk/