I am trying to cre开发者_高级运维ate a subscriber on a map.
here is the code:
type Msg = Message[(SomeObject)] with undoable
class mySub extends Subscriber[Msg,HashMap] {
def notify(pub:HashMap, evt: Msg) = {
evt match{
case Include(NoLo,x) => println(x)
}
}
}
in the notify above if i just print evt I get output:- Include(NoLo, someobject)..but if I try case Include the code wont compile saying found: Include required: Message
Is Include not a subclass of Message? How do you test for different messages like include, remove etc..
I can get this to compile:
import collection.mutable._
import collection.script._
type K = Int
type V = Int
type Msg = Message[(K, V)] with Undoable
class mySub extends Subscriber[Msg, HashMap[K, V]] {
def notify(pub: HashMap[K, V], evt: Msg) = {
(evt: Message[(K, V)]) match {
case Include(NoLo, x) => println(x)
}
}
}
Funny enough, the pattern matching won't compile when Undoable
is mixed in…
A little more verbose but here is what I came up with:
import scala.collection.mutable.{HashMap, Subscriber, Publisher, Undoable, ObservableMap}
import scala.collection.script.{Message, Update, Include, Reset, Remove, Script}
class MySub extends Subscriber[Message[(Int,Int)] with Undoable, ObservableMap[Int, Int]] {
def notify(pub: ObservableMap[Int, Int], evt: Message[(Int, Int)] with Undoable) = evt match {
case update: Update[(Int, Int)] => println("Update: " + update )
case include: Include[(Int, Int)] => println("Include: " + include )
case reset: Reset[(Int, Int)] => println("Reset:" + reset)
case remove: Remove[(Int, Int)] => println("Remove: " + remove)
case script: Script[(Int, Int)] => println("Sript: " + script)
}
}
As you note you have to reference the elem val on subclasses of Message to get the key or the value.
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