固定サイズの Queue

gistfile1.scala

class FixedSizeQueue[A](limit: Int) extends scala.collection.mutable.Queue[A] {                                                                                                                                                               
  override def +=(elem: A) = {                                                                                                                                                                                                                
    super.+=(elem)                                                                                                                                                                                                                            
    while (size > limit) { dequeue }                                                                                                                                                                                                          
    this                                                                                                                                                                                                                                      
  }                                                                                                                                                                                                                                           
  override def +=:(elem: A) = {                                                                                                                                                                                                               
    super.+=:(elem)                                                                                                                                                                                                                           
    while (size > limit) { dequeue }                                                                                                                                                                                                          
    this                                                                                                                                                                                                                                      
  }                                                                                                                                                                                                                                           
}