Scala example source code file (SynchronizedStack.scala)

This example Scala source code file (SynchronizedStack.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

a, boolean, consider, iterator, list, stack, synchronization, synchronizedstack, traversableonce, unit

The SynchronizedStack.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |                                         **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */



package scala
package collection
package mutable


/** This is a synchronized version of the `Stack[T]` class. It
 *  implements a data structure which allows to store and retrieve
 *  objects in a last-in-first-out (LIFO) fashion.
 *
 *  @tparam A    type of the elements contained in this stack.
 *
 *  @author  Matthias Zenger
 *  @version 1.0, 03/05/2004
 *  @since   1
 *  @define Coll `SynchronizedStack`
 *  @define coll synchronized stack
 */
@deprecated("Synchronization via selective overriding of methods is inherently unreliable.  Consider java.util.concurrent.LinkedBlockingDequeue instead.", "2.11.0")
class SynchronizedStack[A] extends Stack[A] {
  import scala.collection.Traversable

  /** Checks if the stack is empty.
   *
   *  @return true, iff there is no element on the stack
   */
  override def isEmpty: Boolean = synchronized { super.isEmpty }

  /** Pushes a single element on top of the stack.
   *
   *  @param  elem        the element to push onto the stack
   */
  override def push(elem: A): this.type = synchronized[this.type] { super.push(elem) }

  /** Push two or more elements onto the stack. The last element
   *  of the sequence will be on top of the new stack.
   *
   *  @param elem1      the first element to push.
   *  @param elem2      the second element to push.
   *  @param elems      the element sequence that will be pushed.
   *  @return           the stack with the new elements on top.
   */
  override def push(elem1: A, elem2: A, elems: A*): this.type = synchronized[this.type] { super.push(elem1, elem2, elems: _*) }

  /** Pushes all elements provided by a traversable object
   *  on top of the stack. The elements are pushed in the order the
   *  traversable object is traversed.
   *
   *  @param  xs        a traversable object
   */
  override def pushAll(xs: TraversableOnce[A]): this.type = synchronized[this.type] { super.pushAll(elems) }

  /** Returns the top element of the stack. This method will not remove
   *  the element from the stack. An error is signaled if there is no
   *  element on the stack.
   *
   *  @return the top element
   */
  override def top: A = synchronized { super.top }

  /** Removes the top element from the stack.
   */
  override def pop(): A = synchronized { super.pop() }

  /**
   * Removes all elements from the stack. After this operation completed,
   * the stack will be empty.
   */
  override def clear(): Unit = synchronized { super.clear() }

  /** Returns an iterator over all elements on the stack. This iterator
   *  is stable with respect to state changes in the stack object; i.e.
   *  such changes will not be reflected in the iterator. The iterator
   *  issues elements in the order they were inserted into the stack
   *  (FIFO order).
   *
   *  @return an iterator over all stack elements.
   */
  override def iterator: Iterator[A] = synchronized { super.iterator }

  /** Creates a list of all stack elements in FIFO order.
   *
   *  @return the created list.
   */
  override def toList: List[A] = synchronized { super.toList }

  /** Returns a textual representation of a stack as a string.
   *
   *  @return the string representation of this stack.
   */
  override def toString = synchronized { super.toString }
}