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ACE_Activation_Queue Class Reference

Reifies a method into a request. Subclasses typically represent necessary state and behavior. More...

#include <Activation_Queue.h>

Collaboration diagram for ACE_Activation_Queue:

[legend]List of all members.

Public Methods
	ACE_Activation_Queue (ACE_Message_Queue< ACE_SYNCH > *new_queue=0, ACE_Allocator *alloc=0, ACE_Allocator *db_alloc=0)
	Constructor.
virtual	~ACE_Activation_Queue (void)
	Destructor.
ACE_Method_Request *	dequeue (ACE_Time_Value *tv=0)
	Dequeue the next available ACE_Method_Request.
int	enqueue (ACE_Method_Request *new_method_request, ACE_Time_Value *tv=0)
	Enqueue the ACE_Method_Request in priority order.
size_t	method_count (void) const
	Get the current number of method objects in the queue.
int	is_empty (void) const
	Returns 1 if the queue is empty, 0 otherwise.
int	is_full (void) const
	Returns 1 if the queue is full, 0 otherwise.
void	dump (void) const
	Dump the state of an request.
ACE_Message_Queue< ACE_SYNCH > *	queue (void) const
	Get a pointer to the underlying queue.
void	queue (ACE_Message_Queue< ACE_SYNCH > *q)
	Set the pointer to the underlying queue.
Public Attributes
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks.
Protected Attributes
ACE_Message_Queue< ACE_SYNCH > *	queue_
	Stores the <Method_Requests>.
int	delete_queue_
	Keeps track of whether we need to delete the queue.
Private Methods
void	operator= (const ACE_Activation_Queue &)
	ACE_Activation_Queue (const ACE_Activation_Queue &)
Private Attributes
ACE_Allocator *	allocator_
	Allocation strategy of the queue.
ACE_Allocator *	data_block_allocator_
	Allocation strategy of the message blocks.

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Detailed Description

Reifies a method into a request. Subclasses typically represent necessary state and behavior.

Maintains a priority-ordered queue of ACE_Method_Request objects. A scheduler class (often derived from ACE_Task) subsequently removes each method request and invokes its call() method.

This class is discussed in depth in the Active Object chapter of POSA2. In that book, it is referred to as an Activation List.

See also:

ACE_Method_Request

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Constructor & Destructor Documentation

ACE_Activation_Queue::ACE_Activation_Queue (  ACE_Message_Queue< ACE_SYNCH > *    new_queue = 0, ACE_Allocator *    alloc = 0, ACE_Allocator *    db_alloc = 0 )

Constructor. Initializes a new activation queue. Parameters: new_queue  The activation queue uses an ACE_Message_Queue to queue and order the method requests. If this argument is 0, a new ACE_Message_Queue is created for this object's use and will be deleted when this object is destroyed. If a non-zero pointer is supplied, the passed object will be used and will not be deleted when this object is destroyed. If an ACE_Task is being created to act as the scheduler, for instance, its ACE_Message_Queue pointer can be passed to this object. alloc  Optional, the allocator to use when allocating ACE_Message_Block instances that wrap the method requests queued to this activation queue. Defaults to ACE_Allocator::instance(). db_alloc  Optional, the allocator to use when allocating data blocks for the ACE_Message_Block instances that wrap the method requests queued to this activation queue. Defaults to ACE_Allocator::instance().

ACE_Activation_Queue::~ACE_Activation_Queue (  void    )  [virtual]

Destructor.

ACE_Activation_Queue::ACE_Activation_Queue (  const ACE_Activation_Queue &    )  [private]

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Member Function Documentation

ACE_Method_Request * ACE_Activation_Queue::dequeue (  ACE_Time_Value *    tv = 0 )

Dequeue the next available ACE_Method_Request. Parameters: tv  If 0, the method will block until a method request is available, else will wait until the absolute time specified in the referenced ACE_Time_Value. This method will return, earlier, however, if queue is closed, deactivated, or when a signal occurs. Return values: Pointer  to the dequeued ACE_Method_Request object. 0  an error occurs; errno contains further information. If the specified timeout elapses, errno will be EWOULDBLOCK.

void ACE_Activation_Queue::dump (  void    )  const

Dump the state of an request.

int ACE_Activation_Queue::enqueue (  ACE_Method_Request *    new_method_request, ACE_Time_Value *    tv = 0 )

Enqueue the ACE_Method_Request in priority order. The priority of the method request is obtained via the priority() method of the queued method request. Priority ordering is determined by the ACE_Message_Queue class; 0 is the lowest priority. Parameters: new_method_request  Pointer to the ACE_Method_Request object to queue. This object's priority() method is called to obtain the priority. tv  If 0, the method will block until the method request can be queued, else will wait until the absolute time specified in the referenced ACE_Time_Value. This method will return, earlier, however, if queue is closed, deactivated, or when a signal occurs. Return values: 0  on success. -1  if an error occurs; errno contains further information. If the specified timeout elapses, errno will be EWOULDBLOCK.

ACE_INLINE int ACE_Activation_Queue::is_empty (  void    )  const

Returns 1 if the queue is empty, 0 otherwise.

ACE_INLINE int ACE_Activation_Queue::is_full (  void    )  const

Returns 1 if the queue is full, 0 otherwise.

ACE_INLINE size_t ACE_Activation_Queue::method_count (  void    )  const

Get the current number of method objects in the queue.

void ACE_Activation_Queue::operator= (  const ACE_Activation_Queue &    )  [private]

ACE_INLINE void ACE_Activation_Queue::queue (  ACE_Message_Queue< ACE_SYNCH > *    q )

Set the pointer to the underlying queue.

ACE_INLINE ACE_Message_Queue< ACE_SYNCH > * ACE_Activation_Queue::queue (  void    )  const

Get a pointer to the underlying queue.

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Member Data Documentation

ACE_Activation_Queue::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

ACE_Allocator* ACE_Activation_Queue::allocator_ [private]

Allocation strategy of the queue.

ACE_Allocator* ACE_Activation_Queue::data_block_allocator_ [private]

Allocation strategy of the message blocks.

int ACE_Activation_Queue::delete_queue_ [protected]

Keeps track of whether we need to delete the queue.

ACE_Message_Queue<ACE_SYNCH>* ACE_Activation_Queue::queue_ [protected]

Stores the <Method_Requests>.

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

• Activation_Queue.h
• Activation_Queue.cpp
• Activation_Queue.i

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