Added new (clean) yii boilerplate

framework/collections/CQueue.php

@@ -0,0 +1,171 @@
+<?php
+/**
+ * This file contains classes implementing the queue feature.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @link http://www.yiiframework.com/
+ * @copyright 2008-2013 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+/**
+ * CQueue implements a queue.
+ *
+ * The typical queue operations are implemented, which include
+ * {@link enqueue()}, {@link dequeue()} and {@link peek()}. In addition,
+ * {@link contains()} can be used to check if an item is contained
+ * in the queue. To obtain the number of the items in the queue,
+ * check the {@link getCount Count} property.
+ *
+ * Items in the queue may be traversed using foreach as follows,
+ * <pre>
+ * foreach($queue as $item) ...
+ * </pre>
+ *
+ * @property Iterator $iterator An iterator for traversing the items in the queue.
+ * @property integer $count The number of items in the queue.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @package system.collections
+ * @since 1.0
+ */
+class CQueue extends CComponent implements IteratorAggregate,Countable
+{
+	/**
+	 * internal data storage
+	 * @var array
+	 */
+	private $_d=array();
+	/**
+	 * number of items
+	 * @var integer
+	 */
+	private $_c=0;
+
+	/**
+	 * Constructor.
+	 * Initializes the queue with an array or an iterable object.
+	 * @param array $data the initial data. Default is null, meaning no initialization.
+	 * @throws CException If data is not null and neither an array nor an iterator.
+	 */
+	public function __construct($data=null)
+	{
+		if($data!==null)
+			$this->copyFrom($data);
+	}
+
+	/**
+	 * @return array the list of items in queue
+	 */
+	public function toArray()
+	{
+		return $this->_d;
+	}
+
+	/**
+	 * Copies iterable data into the queue.
+	 * Note, existing data in the list will be cleared first.
+	 * @param mixed $data the data to be copied from, must be an array or object implementing Traversable
+	 * @throws CException If data is neither an array nor a Traversable.
+	 */
+	public function copyFrom($data)
+	{
+		if(is_array($data) || ($data instanceof Traversable))
+		{
+			$this->clear();
+			foreach($data as $item)
+			{
+				$this->_d[]=$item;
+				++$this->_c;
+			}
+		}
+		elseif($data!==null)
+			throw new CException(Yii::t('yii','Queue data must be an array or an object implementing Traversable.'));
+	}
+
+	/**
+	 * Removes all items in the queue.
+	 */
+	public function clear()
+	{
+		$this->_c=0;
+		$this->_d=array();
+	}
+
+	/**
+	 * @param mixed $item the item
+	 * @return boolean whether the queue contains the item
+	 */
+	public function contains($item)
+	{
+		return array_search($item,$this->_d,true)!==false;
+	}
+
+	/**
+	 * Returns the item at the top of the queue.
+	 * @return mixed item at the top of the queue
+	 * @throws CException if the queue is empty
+	 */
+	public function peek()
+	{
+		if($this->_c===0)
+			throw new CException(Yii::t('yii','The queue is empty.'));
+		else
+			return $this->_d[0];
+	}
+
+	/**
+	 * Removes and returns the object at the beginning of the queue.
+	 * @return mixed the item at the beginning of the queue
+	 * @throws CException if the queue is empty
+	 */
+	public function dequeue()
+	{
+		if($this->_c===0)
+			throw new CException(Yii::t('yii','The queue is empty.'));
+		else
+		{
+			--$this->_c;
+			return array_shift($this->_d);
+		}
+	}
+
+	/**
+	 * Adds an object to the end of the queue.
+	 * @param mixed $item the item to be appended into the queue
+	 */
+	public function enqueue($item)
+	{
+		++$this->_c;
+		$this->_d[]=$item;
+	}
+
+	/**
+	 * Returns an iterator for traversing the items in the queue.
+	 * This method is required by the interface IteratorAggregate.
+	 * @return Iterator an iterator for traversing the items in the queue.
+	 */
+	public function getIterator()
+	{
+		return new CQueueIterator($this->_d);
+	}
+
+	/**
+	 * Returns the number of items in the queue.
+	 * @return integer the number of items in the queue
+	 */
+	public function getCount()
+	{
+		return $this->_c;
+	}
+
+	/**
+	 * Returns the number of items in the queue.
+	 * This method is required by Countable interface.
+	 * @return integer number of items in the queue.
+	 */
+	public function count()
+	{
+		return $this->getCount();
+	}
+}