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ACE_Double_Linked_List< T > Class Template Reference

A double-linked list implementation. More...

#include <Containers_T.h>

Inheritance diagram for ACE_Double_Linked_List< T >:

[legend]Collaboration diagram for ACE_Double_Linked_List< T >:

[legend]List of all members.

Public Types
typedef ACE_Double_Linked_List_Iterator< T >	ITERATOR
typedef ACE_Double_Linked_List_Reverse_Iterator< T >	REVERSE_ITERATOR
Public Methods
	ACE_Double_Linked_List (ACE_Allocator *the_allocator=0)
	ACE_Double_Linked_List (const ACE_Double_Linked_List< T > &)
	Copy constructor.
void	operator= (const ACE_Double_Linked_List< T > &)
	Assignment operator.
	~ACE_Double_Linked_List (void)
	Destructor.
int	is_empty (void) const
	Returns 1 if the container is empty, 0 otherwise.
int	is_full (void) const
	The list is unbounded, so this always returns 0.
T *	insert_tail (T *new_item)
T *	insert_head (T *new_item)
T *	delete_head (void)
	Removes the head of the list and returns a pointer to that item.
T *	delete_tail (void)
	Removes the tail of the list and returns a pointer to that item.
void	reset (void)
	Empty the list.
int	get (T *&item, size_t slot=0)
size_t	size (void) const
	The number of items in the queue.
void	dump (void) const
	Dump the state of an object.
int	remove (T *n)
	Use DNode address directly.
Public Attributes
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks.
Protected Methods
void	delete_nodes (void)
	Delete all the nodes in the list.
void	copy_nodes (const ACE_Double_Linked_List< T > &rhs)
	Copy nodes from <rhs> into this list.
void	init_head (void)
	Setup header pointer. Called after we create the head node in ctor.
int	insert_element (T *new_item, int before=0, T *old_item=0)
	Constant time insert a new item into the list structure.
int	remove_element (T *item)
	Constant time delete an item from the list structure.
Protected Attributes
T *	head_
	Head of the circular double-linked list.
size_t	size_
	Size of this list.
ACE_Allocator *	allocator_
	Allocation Strategy of the queue.
Friends
class	ACE_Double_Linked_List_Iterator_Base< T >
class	ACE_Double_Linked_List_Iterator< T >
class	ACE_Double_Linked_List_Reverse_Iterator< T >

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Detailed Description

template<class T>
class ACE_Double_Linked_List< T >

A double-linked list implementation.

This implementation of an unbounded double-linked list uses a circular linked list with a dummy node. It is pretty much like the <ACE_Unbounded_Queue> except that it allows removing of a specific element from a specific location. Notice that this class is an implementation of a very simple data structure. This is *NOT* a container class. You can use the class to implement other contains classes but it is *NOT* a general purpose container class. The parameter class *MUST* have members T* prev and T* next and users of this class are responsible to follow the general rules of using double-linked lists to maintaining the list integrity. If you need a double linked container class, use the DLList class which is a container but delegates to the Double_Linked_List class.

Requirements and Performance Characteristics

• Internal Structure Double Linked List
• Duplicates allowed? Yes
• Random access allowed? No
• Search speed N/A
• Insert/replace speed Linear
• Iterator still valid after change to container? Yes
• Frees memory for removed elements? No
• Items inserted by Value
• Requirements for contained type
  1. Default constructor
  2. Copy constructor
  3. operator=

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Member Typedef Documentation

template<class T> typedef ACE_Double_Linked_List_Iterator<T> ACE_Double_Linked_List< T >::ITERATOR

template<class T> typedef ACE_Double_Linked_List_Reverse_Iterator<T> ACE_Double_Linked_List< T >::REVERSE_ITERATOR

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Constructor & Destructor Documentation

template<class T> ACE_Double_Linked_List< T >::ACE_Double_Linked_List (  ACE_Allocator *    the_allocator = 0 )

Initialize an empy list using the allocation strategy specified by the user. If none is specified, then use default allocation strategy.

template<class T> ACE_Double_Linked_List< T >::ACE_Double_Linked_List (  const ACE_Double_Linked_List< T > &    )

Copy constructor. Create a double linked list that is a copy of the provided parameter.

template<class T> ACE_Double_Linked_List< T >::~ACE_Double_Linked_List (  void    )

Destructor. Clean up the memory allocated for the nodes of the list.

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Member Function Documentation

template<class T> void ACE_Double_Linked_List< T >::copy_nodes (  const ACE_Double_Linked_List< T > &    rhs )  [protected]

Copy nodes from <rhs> into this list. Copy the elements of the provided list by allocated new nodes and assigning them with the proper data.

template<class T> T * ACE_Double_Linked_List< T >::delete_head (  void    )

Removes the head of the list and returns a pointer to that item. Removes and returns the first <item> in the list. Returns internal node's address on success, 0 if the queue was empty. This method will *not* free the internal node. Reimplemented in ACE_DLList< T >.

template<class T> void ACE_Double_Linked_List< T >::delete_nodes (  void    )  [protected]

Delete all the nodes in the list. Removes and deallocates memory for all of the list nodes.

template<class T> T * ACE_Double_Linked_List< T >::delete_tail (  void    )

Removes the tail of the list and returns a pointer to that item. Removes and returns the last <item> in the list. Returns internal nodes's address on success, 0 if the queue was empty. This method will *not* free the internal node. Reimplemented in ACE_DLList< T >.

template<class T> void ACE_Double_Linked_List< T >::dump (  void    )  const

Dump the state of an object. Reimplemented in ACE_DLList< T >.

template<class T> int ACE_Double_Linked_List< T >::get (  T *&    item, size_t    slot = 0 )

Iterates through the list to the desired index and assigns the provides pointer with the address of the node occupying that index.

template<class T> void ACE_Double_Linked_List< T >::init_head (  void    )  [protected]

Setup header pointer. Called after we create the head node in ctor. Initialize the head pointer so that the list has a dummy node.

template<class T> int ACE_Double_Linked_List< T >::insert_element (  T *    new_item, int    before = 0, T *    old_item = 0 )  [protected]

Constant time insert a new item into the list structure. Insert a new_item into the list. It will be added before or after old_item. Default is to insert the new item *after* <head_>. Return 0 if succeed, -1 if error occured.

template<class T> T * ACE_Double_Linked_List< T >::insert_head (  T *    new_item )

Provides constant time insertion at the head of the list.

template<class T> T * ACE_Double_Linked_List< T >::insert_tail (  T *    new_item )

Provides constant time insertion at the end of the list structure.

template<class T> int ACE_Double_Linked_List< T >::is_empty (  void    )  const

Returns 1 if the container is empty, 0 otherwise. Performs constant time check to determine if the list is empty.

template<class T> int ACE_Double_Linked_List< T >::is_full (  void    )  const

The list is unbounded, so this always returns 0. Since the list is unbounded, the method simply returns 0.

template<class T> void ACE_Double_Linked_List< T >::operator= (  const ACE_Double_Linked_List< T > &    )

Assignment operator. Perform a deep copy of the provided list by first deleting the nodes of the lhs and then copying the nodes of the rhs.

template<class T> int ACE_Double_Linked_List< T >::remove (  T *    n )

Use DNode address directly. Constant time removal of an item from the list using it's address. Reimplemented in ACE_DLList< T >.

template<class T> int ACE_Double_Linked_List< T >::remove_element (  T *    item )  [protected]

Constant time delete an item from the list structure. Remove item from the list. Return 0 if succeed, -1 otherwise. Notice that this function checks if item is <head_> and either its <next_> or <prev_> is NULL. The function resets item's <next_> and <prev_> to 0 to prevent clobbering the double-linked list if a user tries to remove the same node again.

template<class T> void ACE_Double_Linked_List< T >::reset (  void    )

Empty the list. Reset the <ACE_Double_Linked_List> to be empty. Notice that since no one is interested in the items within, This operation will delete all items.

template<class T> size_t ACE_Double_Linked_List< T >::size (  void    )  const

The number of items in the queue. Constant time call to return the current size of the list.

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Friends And Related Function Documentation

template<class T> friend class ACE_Double_Linked_List_Iterator< T > [friend]

Reimplemented in ACE_DLList< T >.

template<class T> friend class ACE_Double_Linked_List_Iterator_Base< T > [friend]

template<class T> friend class ACE_Double_Linked_List_Reverse_Iterator< T > [friend]

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Member Data Documentation

template<class T> ACE_Double_Linked_List< T >::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

template<class T> ACE_Allocator* ACE_Double_Linked_List< T >::allocator_ [protected]

Allocation Strategy of the queue.

template<class T> T* ACE_Double_Linked_List< T >::head_ [protected]

Head of the circular double-linked list.

template<class T> size_t ACE_Double_Linked_List< T >::size_ [protected]

Size of this list.

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

• /export2/deucetmp/bala/release_try/ACE_wrappers/ace/Containers_T.h
• /export2/deucetmp/bala/release_try/ACE_wrappers/ace/Containers_T.cpp

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