scala.collection.mutable.QueueProxy.scala Maven / Gradle / Ivy
/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala
package collection
package mutable
/** `Queue` objects implement data structures that allow to
* insert and retrieve elements in a first-in-first-out (FIFO) manner.
*
* @tparam A type of the elements in this queue proxy.
*
* @author Matthias Zenger
* @since 1
*/
@deprecated("proxying is deprecated due to lack of use and compiler-level support", "2.11.0")
trait QueueProxy[A] extends Queue[A] with Proxy {
def self: Queue[A]
/** Access element number `n`.
*
* @return the element at index `n`.
*/
override def apply(n: Int): A = self.apply(n)
/** Returns the length of this queue.
*/
override def length: Int = self.length
/** Checks if the queue is empty.
*
* @return true, iff there is no element in the queue.
*/
override def isEmpty: Boolean = self.isEmpty
/** Inserts a single element at the end of the queue.
*
* @param elem the element to insert
*/
override def +=(elem: A): this.type = { self += elem; this }
/** Adds all elements provided by an iterator at the end of the queue. The
* elements are prepended in the order they are given out by the iterator.
*
* @param it an iterator
*/
override def ++=(it: TraversableOnce[A]): this.type = {
self ++= it
this
}
/** Adds all elements to the queue.
*
* @param elems the elements to add.
*/
override def enqueue(elems: A*) { self ++= elems }
/** Returns the first element in the queue, and removes this element
* from the queue.
*
* @return the first element of the queue.
*/
override def dequeue(): A = self.dequeue()
/** Returns the first element in the queue, or throws an error if there
* is no element contained in the queue.
*
* @return the first element.
*/
override def front: A = self.front
/** Removes all elements from the queue. After this operation is completed,
* the queue will be empty.
*/
override def clear(): Unit = self.clear()
/** Returns an iterator over all elements on the queue.
*
* @return an iterator over all queue elements.
*/
override def iterator: Iterator[A] = self.iterator
/** This method clones the queue.
*
* @return a queue with the same elements.
*/
override def clone(): Queue[A] = new QueueProxy[A] {
def self = QueueProxy.this.self.clone()
}
}