WOscPriorityQueue Class Reference

#include <WOscPriorityQueue.h>

Inherited by WOscReceiver [private].

List of all members.

Public Member Functions
	WOscPriorityQueue (int initialCapacity)
virtual	~WOscPriorityQueue ()
void	InsertItem (WOscQueueItem *item)
WOscQueueItem *	RemoveEarliestItem ()
WOscTimeTag	GetEarliestTimeTag ()
int	GetNumItems ()

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Detailed Description

Sorts queue-items by their time tag when inserted. The earliest items can be queried and/or removed.

Remarks:

The queue items are stored internally only by reference, the user must control the life (allocation and deletion) of the queue items.

See also:

WOscQueueItem

Definition at line 115 of file WOscPriorityQueue.h.

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Constructor & Destructor Documentation

WOscPriorityQueue::WOscPriorityQueue (  int  initialCapacity  )

Constructor. Constructs an empty priority queue with a capacity of "initialCapacity". Parameters: initialCapacity  The initial capacity (how many items can be inserted until doubleCapacity() will be called. See also: WOscPriorityQueue::doubleCapacity() Definition at line 58 of file WOscPriorityQueue.cpp. { /* allocate list (queue) */ m_listCapacity = initialCapacity; m_list = new WOscQueueItem*[initialCapacity]; /* reset list (no items) */ for( int i = 0; i < initialCapacity; i++ ) m_list[i] = NULL; m_itemsInList = 0; }

WOscPriorityQueue::~WOscPriorityQueue (   )  [virtual]

Destructor. All elements which are not removed from the priority-queue get deleted automatically. Definition at line 77 of file WOscPriorityQueue.cpp. References GetNumItems(), and RemoveEarliestItem(). { /* empty queue as long there are items in the queue*/ while( GetNumItems() > 0 ) delete RemoveEarliestItem(); delete [] m_list; }

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Member Function Documentation

WOscTimeTag WOscPriorityQueue::GetEarliestTimeTag (   )

Returns the timetag of the earliest item. Searches by linearly traversing the queue. Returns: The time-tag of the earliest item. If no time-tag smaller than WOscTimeTag::getLargestTimeTag() can be found WOscTimeTag::getLargestTimeTag() will be returned. Definition at line 143 of file WOscPriorityQueue.cpp. References WOscTimeTag::GetLargestTimeTag(). Referenced by WOscReceiver::ManagePriorityQueue(). { WOscTimeTag smallest = WOscTimeTag::GetLargestTimeTag(); for ( int i = 0; i < m_itemsInList; i++ ) if ( *m_list[i] < smallest ) smallest = *m_list[i]; return smallest; }

int WOscPriorityQueue::GetNumItems (   )

Returns the number of items in the queue. Returns: The number of items in the queue. Definition at line 216 of file WOscPriorityQueue.cpp. Referenced by WOscReceiver::ManagePriorityQueue(), and ~WOscPriorityQueue(). { return m_itemsInList; }

void WOscPriorityQueue::InsertItem (  WOscQueueItem *  item  )

Inserts an item into the queue. Items are simply inserted and not ordered. Remarks: WOscPriorityQueue::getEarliestTimeTag() then checks the time-tags and returns the earliest. Definition at line 96 of file WOscPriorityQueue.cpp. { // check capacity, double if necessary if ( m_itemsInList == m_listCapacity ) DoubleCapacity(); // insert pointer to element and increment population m_list[m_itemsInList++] = item; }

WOscQueueItem * WOscPriorityQueue::RemoveEarliestItem (   )

Removes the earliest item from the queue and returns it. Returns: The pointer to the earliest item removed from the queue. Exceptions: WOscException  When trying to remove from an empty queue. Remarks: When removed, the user (caller) has to care about the deletion of that element, since the queue is only an itermediate buffer. When removed the queue does not know anything about this object anymore. Definition at line 187 of file WOscPriorityQueue.cpp. References ERR_REMOVE_FROM_EMPTY_QUEUE. Referenced by WOscReceiver::ManagePriorityQueue(), and ~WOscPriorityQueue(). { WOscQueueItem* result; int smallestIdx = 0; if ( m_itemsInList == 0 ) throw WOscException(ERR_REMOVE_FROM_EMPTY_QUEUE, __FILE__, __LINE__); /* traverse the queue and */ for ( int i = 0; i < m_itemsInList; i++ ) /* compare time-tags */ if ( *m_list[smallestIdx] > *m_list[i] ) smallestIdx = i; /* save pointer before removing it */ result = m_list[smallestIdx]; RemoveItem(smallestIdx); return result; }

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The documentation for this class was generated from the following files:

• WOscPriorityQueue.h
• WOscPriorityQueue.cpp

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