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/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003-2007, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
// $Id$
package scala.collection.mutable
/** <code>History[A, B]</code> objects may subscribe to events of
* type <code>A</code> published by an object of type <code>B</code>.
* The history subscriber object records all published events
* up to maximum number of <code>maxHistory</code> events.
*
* @author Matthias Zenger
* @version 1.0, 08/07/2003
*/
@serializable
class History[A, B] extends AnyRef with Subscriber[A, B] with Iterable[Pair[B, A]] {
protected val log: Queue[Pair[B, A]] = new Queue[Pair[B, A]]
val maxHistory: Int = 1000
/**
* @param pub ...
* @param event ...
*/
def notify(pub: B, event: A): Unit = {
if (log.length >= maxHistory) {
val old = log.dequeue;
}
log.enqueue(Pair(pub, event))
}
def elements: Iterator[Pair[B, A]] = log.elements
def events: Iterator[A] = log.elements.map { case Pair(_, e) => e }
def size: Int = log.length
def clear(): Unit = log.clear
}
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