stashin commit so Iulian can play with it
This commit is contained in:
parent
e85d996fd5
commit
be74eb835b
10 changed files with 935 additions and 45 deletions
|
|
@ -5,6 +5,7 @@
|
|||
package akka.japi
|
||||
|
||||
import scala.Some
|
||||
import scala.util.control.NoStackTrace
|
||||
|
||||
/**
|
||||
* A Function interface. Used to create first-class-functions is Java.
|
||||
|
|
@ -44,6 +45,50 @@ trait Creator[T] {
|
|||
def create(): T
|
||||
}
|
||||
|
||||
object PurePartialFunction {
|
||||
case object NoMatch extends RuntimeException with NoStackTrace
|
||||
}
|
||||
|
||||
/**
|
||||
* Helper for implementing a *pure* partial function: it will possibly be
|
||||
* invoked multiple times for a single “application”, because its only abstract
|
||||
* method is used for both isDefinedAt() and apply(); the former is mapped to
|
||||
* `isCheck == true` and the latter to `isCheck == false` for those cases where
|
||||
* this is important to know.
|
||||
*
|
||||
* {{{
|
||||
* new PurePartialFunction<Object, String>() {
|
||||
* public String apply(Object in, boolean isCheck) {
|
||||
* if (in instanceof TheThing) {
|
||||
* if (isCheck) return null; // to spare the expensive or side-effecting code
|
||||
* return doSomethingWithTheThing((TheThing) in);
|
||||
* } else {
|
||||
* throw noMatch();
|
||||
* }
|
||||
* }
|
||||
* }
|
||||
* }}}
|
||||
*
|
||||
* The typical use of partial functions from Akka looks like the following:
|
||||
*
|
||||
* {{{
|
||||
* if (pf.isDefinedAt(x)) pf.apply(x)
|
||||
* }}}
|
||||
*
|
||||
* i.e. it will first call `PurePartialFunction.apply(x, true)` and if that
|
||||
* does not throw `noMatch()` it will continue with calling
|
||||
* `PurePartialFunction.apply(x, false)`.
|
||||
*/
|
||||
abstract class PurePartialFunction[A, B] extends scala.runtime.AbstractFunction1[A, B] with PartialFunction[A, B] {
|
||||
import PurePartialFunction._
|
||||
|
||||
def apply(x: A, isCheck: Boolean): B
|
||||
|
||||
final def isDefinedAt(x: A): Boolean = try { apply(x, true); true } catch { case NoMatch ⇒ false }
|
||||
final def apply(x: A): B = try apply(x, false) catch { case NoMatch ⇒ throw new MatchError }
|
||||
final def noMatch(): RuntimeException = NoMatch
|
||||
}
|
||||
|
||||
/**
|
||||
* This class represents optional values. Instances of <code>Option</code>
|
||||
* are either instances of case class <code>Some</code> or it is case
|
||||
|
|
@ -117,4 +162,6 @@ object Util {
|
|||
* Given a Class returns a Scala Manifest of that Class
|
||||
*/
|
||||
def manifest[T](clazz: Class[T]): Manifest[T] = Manifest.classType(clazz)
|
||||
|
||||
def arrayToSeq[T](arr: Array[T]): Seq[T] = arr.toSeq
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue