Polyglot Programming @ Jax.de 2010
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The document discusses polyglot programming on the Java Virtual Machine (JVM). It introduces the speaker and provides background on Java. It notes that while Java is mature, other JVM languages like Groovy, Scala, and Clojure have evolved faster with features like closures, pattern matching, and immutability. These languages are highly interoperable with Java and allow for reduced verbosity. The document demonstrates features of these languages and provides examples of domains where polyglot programming is common like web development, next-gen data stores, and build systems. It encourages the audience to try these languages on the JVM.
![Closures (or Functions)
(defn adder [a b] (+ a b))](https://image.slidesharecdn.com/jax10polyglotprogramming-100510032226-phpapp01/85/Polyglot-Programming-Jax-de-2010-20-320.jpg)
![Enhanced Switch
def letterGrade(grade) {
switch(grade) {
case 90..100: return ‘A‘
case 80..<90: return ‘B‘
case 70..<80: return ‘C‘
case 60..<70: return ‘D‘
case 0..<60: return ‘F‘
case ~"[ABCDFabcdf]":
return grade.toUpperCase()
}
throw new IllegalArgumentException
(‘invalid grade ‘+grade)
}](https://image.slidesharecdn.com/jax10polyglotprogramming-100510032226-phpapp01/85/Polyglot-Programming-Jax-de-2010-22-320.jpg)
![Enhanced Switch
(defn letter-grade [grade]
(cond
(in grade 90 100) "A"
(in grade 80 90) "B"
(in grade 70 80) "C"
(in grade 60 70) "D"
(in grade 0 60) "F"
(re-find #"[ABCDFabcdf]" grade)
(.toUpperCase grade)))](https://image.slidesharecdn.com/jax10polyglotprogramming-100510032226-phpapp01/85/Polyglot-Programming-Jax-de-2010-24-320.jpg)
Polyglot Programming @ Jax.de 2010
- 1. Andres Almiray | Canoo Engineering AG Polyglot Programming in the JVM Or how I Learned to Stop Worrying and Love the JVM
- 2. About the speaker Java developer since the beginning True believer in open source Groovy committer since 2007 Project lead of the Griffon framework Currently working for
- 3. Some facts about Java Previous name was Oak. Bonus points for knowing its real name before that Made its public appearance in 1995 C/C++ were king at the time Networking, multithreading were baked right into the language Developers came for the applets and stayed for the components (JEE and all that jazz)
- 4. However... It is already in its teens It has not seen a major feature upgrade since JDK5 was released back in 2004 -> generics (and we do know how that turned out to be, don’t we?) JDK7 has been delayed again (late 2010). Some features might or might not make the cut (the closures debacle)
- 5. More so... It is rather verbose when compared to how other languages do the same task Its threading features are no longer enough. Concurrent programs desperately cry for immutability these days
- 6. Truth or myth? Is Java oftenly referred as overengineered? Can you build a Java based web application (for arguments sake a basic Twitter clone) in less than a day‘s work WITHOUT an IDE? Did James Gosling ever say he was threatened with bodily harm should operator overloading find its way into Java?
- 7. The JVM is a great place to work however Java makes it painful sometimes...
- 8. What can we do about it?!
- 10. Disclaimer (this is not a bash-the-other-languages talk)
- 12. Standard Beans public class Bean { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } }
- 13. Standard Beans public class Bean { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } }
- 14. Standard Beans class Bean { String name }
- 15. Standard Beans class Bean(var name:String) class Bean { @scala.reflect.BeanProperty var name: String }
- 16. Standard Beans (defstruct Bean :name)
- 17. Closures (or Functions) public interface Adder { int add(int a, int b); } public class MyAdder implements Adder { public int add(int a, int b) { return a + b; } }
- 18. Closures (or Functions) def adder = { a , b -> a + b }
- 19. Closures (or Functions) def adder(a: Int, b: Int) = a + b
- 20. Closures (or Functions) (defn adder [a b] (+ a b))
- 21. Enhanced switch char letterGrade(int grade) { if(grade >= 0 && grade <= 60) return ‘F‘; if(grade > 60 && grade <= 70) return ‘D‘; if(grade > 70 && grade <= 80) return ‘C‘; if(grade > 80 && grade <= 90) return ‘B‘; if(grade > 90 && grade <= 100) return ‘A‘; throw new IllegalArgumentException(‘invalid grade ‘+grade); }
- 22. Enhanced Switch def letterGrade(grade) { switch(grade) { case 90..100: return ‘A‘ case 80..<90: return ‘B‘ case 70..<80: return ‘C‘ case 60..<70: return ‘D‘ case 0..<60: return ‘F‘ case ~"[ABCDFabcdf]": return grade.toUpperCase() } throw new IllegalArgumentException (‘invalid grade ‘+grade) }
- 23. Enhanced Switch val VALID_GRADES = Set("A", "B", "C", "D", "F") def letterGrade(value: Any):String = value match { case x:Int if (90 to 100).contains(x) => "A" case x:Int if (80 to 90).contains(x) => "B" case x:Int if (70 to 80).contains(x) => "C" case x:Int if (60 to 70).contains(x) => "D" case x:Int if (0 to 60).contains(x) => "F" case x:String if VALID_GRADES(x.toUpperCase) => x.toUpperCase() }
- 24. Enhanced Switch (defn letter-grade [grade] (cond (in grade 90 100) "A" (in grade 80 90) "B" (in grade 70 80) "C" (in grade 60 70) "D" (in grade 0 60) "F" (re-find #"[ABCDFabcdf]" grade) (.toUpperCase grade)))
- 26. All of these are true Java can call Groovy, Scala and Clojure classes as if they were Java classes Groovy, Scala and Clojure can call Java code without breaking a sweat In other words, interoperability with Java is a given. No need for complicated bridges between languages (i.e. JSR 223)
- 27. Ok, so... What else can these languages do?
- 28. All of them Native syntax for collection classes Everything is an object Closures! Regular expressions as first class citizens Operator overloading
- 29. Groovy Metaprogramming (HOT!) both at buildtime and runtime Builders Healthy ecosystem: Grails, Griffon, Gant, Gradle, Spock, Gaelyk, Gpars, CodeNarc, etc... Not an exhaustive list of features!
- 30. Scala Richer type system Type inference Pattern matching (case classes) Actor model Not an exhaustive list of features!
- 31. Clojure Data as code and viceversa Immutable structures STM Not an exhaustive list of features!
- 32. Demo
- 33. Other places where you‘ll find Polyglot Programming
- 34. Web app development XML SQL JavaScript JSON CSS Flash/Flex/ActionScript
- 35. Next-Gen datastores (NoSQL) FleetDB -> Clojure FlockDB -> Scala CouchDB, Riak -> Erlang btw watch out for Polyglot Persistence ;-)
- 36. Build systems Gradle, Gant -> Groovy Rake -> Ruby/JRuby Maven3 -> XML, Groovy, Ruby
- 37. Parting thoughts Java (the language) may have reached its maturity feature wise Other JVM languages evolved faster Polyglot Programming is not a new concept Download and play with each of the demoed languages, maybe one of them strikes your fancy
- 38. Resources