blob: 43be62960235c9217aa383521508c1c255a1b66a (
plain) (
tree)
|
|
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2003, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
** $Id$
\* */
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;
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;
}
|