![extractor object
unapply : Input => Optional[Output]
case class is lucky](https://image.slidesharecdn.com/scala-the-good-parts-160115093250/75/scala-thegoodparts-22-2048.jpg?cb=1668594329)
![Partial Function Tip
scala> val m = Map(1->2, 2->3)
m: scala.collection.immutable.Map[Int,Int] = Map(1 -> 2, 2 -> 3)
scala> m.collect({case (k, v) if k % 2 ==0 => (k,v) })
res7: scala.collection.immutable.Map[Int,Int] = Map(2 -> 3)
scala> m collect {case (k, v) if k % 2 ==0 => (k,v) }
res7: scala.collection.immutable.Map[Int,Int] = Map(2 -> 3)](https://image.slidesharecdn.com/scala-the-good-parts-160115093250/75/scala-thegoodparts-31-2048.jpg?cb=1668594329)
![what a route looks like
[Http Method] [path] [controller method]
GET / controllers.Application.main
POST / controllers.Application.index
# Map static resources from the /public folder to the /assets URL path
GET /assets/*file controllers.Assets.at(path="/public", file)
GET /webjars/*file controllers.WebJarAssets.at(file)](https://image.slidesharecdn.com/scala-the-good-parts-160115093250/75/scala-thegoodparts-54-2048.jpg?cb=1668594329)
Scala the-good-parts
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Scala the-good-parts
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- 11. Flexible Parameters But not friendly to Javaers
- 12. case class
- 13. How you do it in Java Way?
- 14. IDEs can help
- 15. Library can help Commons Lang Google Guava Lombok
- 16. Let’s do it in Scala Way!
- 17. tuples
- 19. special `apply` in companion object
- 21. Pattern Matching Takes Them All
- 22. extractor object unapply : Input => Optional[Output] case class is lucky
- 23. monad and container objects
- 24. monad and container objects you have met Option, right? But it’s more than Some or None!
- 25. Monad is too academic, let’s know it in an easy way import scala.collection._Go and Explore…
- 26. function Rocks
- 28. Partial Applied functions Are NOT Partial Functions
- 31. Partial Function Tip scala> val m = Map(1->2, 2->3) m: scala.collection.immutable.Map[Int,Int] = Map(1 -> 2, 2 -> 3) scala> m.collect({case (k, v) if k % 2 ==0 => (k,v) }) res7: scala.collection.immutable.Map[Int,Int] = Map(2 -> 3) scala> m collect {case (k, v) if k % 2 ==0 => (k,v) } res7: scala.collection.immutable.Map[Int,Int] = Map(2 -> 3)
- 33. high-order Functions Try Function as return value
- 34. How about Java8? Both Cool~ as long as you like
- 36. REPL 快速验证你的疑惑和想法
- 37. The JVMFamily
- 38. What comes into your mind when u hear the Java word?
- 42. Wonderful Plugins SBT Native Packager Plugin sbt-assembly sbt-dependency-graph you favoured IDEs’ Plugins
- 43. Concurrency in another way
- 44. SIP14 Rocks - Futures and Promises Composable !
- 45. SIP14 Rocks - Futures and Promises
- 46. Actor Model Don’t be silly
- 47. A Best Practice Of Message Passing Concurrency
- 48. Hello Actor Gravity u can’t escape
- 49. IoCWisely
- 51. web another way
- 53. route - the central hub
- 54. what a route looks like [Http Method] [path] [controller method] GET / controllers.Application.main POST / controllers.Application.index # Map static resources from the /public folder to the /assets URL path GET /assets/*file controllers.Assets.at(path="/public", file) GET /webjars/*file controllers.WebJarAssets.at(file)
- 55. Perfect For Web APIScenarios
- 56. Breakingout of Web Containers
- 57. make a killing with big data
- 58. do you know DryadLINQ Microsoftdoes NOT always suck
- 59. from single framework to family
- 61. You know Scala Collections well, you play with Spark well ；） val textFile = spark.textFile("hdfs://...") val errors = textFile.filter(line => line.contains("ERROR")) errors.count() errors.filter(line => line.contains("MySQL")).count() errors.filter(line => line.contains("MySQL")).collect()
- 63. ImmediatelyVS. Wait a moment
- 64. – who said that?! “Where the fucking awesome type system of scala?”
- 65. Scala wisely
- 66. 扶墙老师はpuristない
- 67. Find your own toolbox not ONLY a Hammer
- 69. string interpolation wisely @see also org.slf4j.helpers.MessageFormatter
- 70. About Implicit 1. 如果有普遍的共识 和约定的， 可以使用； 2. 否则，不建议使用！
- 72. No Perfect Annotation Solution UglyThing macross
- 73. enumeration wisely or sealed trait?
- 76. Questions?
- 77. over