PimpingJavaLibraries

Using many Java libraries from Scala is unpleasant at best. Fortunately, Implicit Conversions in Scala provide a great way to cut through the madness! Follow along (git log -p), as each commit explains what is being done, and why.

The "Pimp my Library" pattern was proposed by Martin Odersky in 2006. A couple examples were provided, here's one of them:

class RichArray[T](value: Array[T]) {
  def append(other: Array[T]): Array[T] = {
    val result = new Array[T](value.length + other.length)
    Array.copy(value, 0, result, 0, value.length)
    Array.copy(other, 0, result, value.length, other.length)
    result
  }
}

implicit def enrichArray[T](xs: Array[T]) = new RichArray[T]

With these definitions, we can do:

val first: Array[Int] = List(1,2,3).toArray
val last: Array[Int] = List(4,5,6).toArray

first.append(last)

which converts first into a RichArray[T], then calls append, which returns a normal Array[T]

Current libraries:

• Jackson JSON parser