TAO::ObjectKey_Table Class Reference

Table that maintains the set of ObjectKey's seen by the ORB. More...

#include <ObjectKey_Table.h>

Collaboration diagram for TAO::ObjectKey_Table:

[legend]List of all members.

Public Member Functions
	ObjectKey_Table (void)
	Default Constructor and destructor..
	~ObjectKey_Table (void)
int	init (TAO_ORB_Core *orb)
int	destroy (void)
	Iterates and unbinds the contents of the table.
int	bind (const ObjectKey &key, Refcounted_ObjectKey *&key_new)
	Bind the ObjectKey in the table.
int	unbind (TAO::Refcounted_ObjectKey *&key)
	Unbind an ObjectKey from the table.
Protected Member Functions
int	bind_i (const ObjectKey &key, Refcounted_ObjectKey *&key_new)
	Implementation for bind ().
int	unbind_i (Refcounted_ObjectKey *&key)
	Implementation for unbind ().
Private Types
typedef ACE_RB_Tree< TAO::ObjectKey, TAO::Refcounted_ObjectKey *, TAO::Less_Than_ObjectKey, ACE_Null_Mutex >	TABLE
Private Attributes
ACE_Lock *	lock_
	Lock for the table.
TABLE	table_
	Table that contains the data.

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Detailed Description

Table that maintains the set of ObjectKey's seen by the ORB.

The ORB maintains one table for the whole ORB. ObjectKeys generated by the ORB or the ones seen by the ORB from remote ORB's are stored here. The ObjectKeys are stored through a wrapper which encapsulates the refcount on them. This class actually provides the synchronization mechanism for manipulating the reference counts on the object keys provided by the wrapper class.

This class does not offer a find () call with a reason. The call to bind () will return a pointer which is expected to be cached by the client/caller and use the pointer in every invocation.

Note:

This class uses the ACE_RB_Tree to maintain the table of ObjectKeys. The RB_Tree has good insertion and lookup properties. Its Iteration properties are not that good, but we dont need to do much iteration unless we are closing down the table.

The reasons to use RB_Tree are its good dynamic properties. We should try to strategize the class to use either a Hash_Map or a RB_Tree based on some runtime option. For that we need an adapter class in ACE, like an ACE_Lock_Adapter class. We will do that if our instrumentation shows the need for it.

Definition at line 88 of file ObjectKey_Table.h.

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Member Typedef Documentation

typedef ACE_RB_Tree<TAO::ObjectKey, TAO::Refcounted_ObjectKey *, TAO::Less_Than_ObjectKey, ACE_Null_Mutex> TAO::ObjectKey_Table::TABLE [private]

Definition at line 130 of file ObjectKey_Table.h.

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Constructor & Destructor Documentation

TAO::ObjectKey_Table::ObjectKey_Table

(

void

)

Default Constructor and destructor..

Definition at line 37 of file ObjectKey_Table.cpp.

References ObjectKey_Table().

Referenced by ObjectKey_Table().

  : lock_ (0)
  , table_ ()
{

}

TAO::ObjectKey_Table::~ObjectKey_Table

(

void

)

Definition at line 44 of file ObjectKey_Table.cpp.

References ACE_RB_Tree< EXT_ID, INT_ID, COMPARE_KEYS, ACE_LOCK >::close(), lock_, table_, and ~ObjectKey_Table().

Referenced by ~ObjectKey_Table().

{
  this->table_.close ();
  delete this->lock_;
}

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Member Function Documentation

int TAO::ObjectKey_Table::bind	(	const ObjectKey &	key,
		Refcounted_ObjectKey *&	key_new
	)

Bind the ObjectKey in the table.

Bind an ObjectKey in the table and return a pointer to the Refcounted_ObjectKey which the client can use. If the ObjectKey is already available in the table, this operation just increments the refcount on the ObjectKey. If the ObjectKey is new it is bounded to the table. Returns a 0 on success and a -1 on failure.

Definition at line 61 of file ObjectKey_Table.cpp.

References ACE_GUARD_RETURN, bind_i(), ACE_RB_Tree< EXT_ID, INT_ID, COMPARE_KEYS, ACE_LOCK >::find(), and table_.

{
  key_new = 0;

  int retval = 0;

  {
    ACE_GUARD_RETURN (ACE_Lock,
                      ace_mon,
                      *this->lock_,
                      0);

    // This is a tradeoff.. We could avoid this two stage process of
    // using a find () and then a bind () , which would make things
    // efficient. BUT we may have to do allocation upfront and delete if
    // bind () returns with an entry. We take one of the routes that
    // avoids allocation.
    retval = this->table_.find (key,
                                key_new);

    if (retval == -1)
      {
        return this->bind_i (key,
                             key_new);
      }

    (void) key_new->incr_refcount ();
  }

  return retval;
}

int TAO::ObjectKey_Table::bind_i	(	const ObjectKey &	key,
		Refcounted_ObjectKey *&	key_new
	)			[protected]

Implementation for bind ().

Definition at line 140 of file ObjectKey_Table.cpp.

References ACE_NEW_RETURN, ACE_RB_Tree< EXT_ID, INT_ID, COMPARE_KEYS, ACE_LOCK >::bind(), bind_i(), and table_.

Referenced by bind(), and bind_i().

{
  ACE_NEW_RETURN (key_new,
                  TAO::Refcounted_ObjectKey (key),
                  -1);

  int const retval =  this->table_.bind (key, key_new);

  if (retval != -1)
    {
      key_new->incr_refcount ();
    }
  else
    {
      key_new->decr_refcount ();
    }

  return retval;
}

int TAO::ObjectKey_Table::destroy

(

void

)

Iterates and unbinds the contents of the table.

Definition at line 115 of file ObjectKey_Table.cpp.

References ACE_GUARD_RETURN, destroy(), ACE_RB_Tree< EXT_ID, INT_ID, COMPARE_KEYS, ACE_LOCK >::end(), table_, and ACE_RB_Tree< EXT_ID, INT_ID, COMPARE_KEYS, ACE_LOCK >::unbind().

Referenced by destroy().

{
  if (this->table_.current_size ())
    {
      ACE_GUARD_RETURN (ACE_Lock,
                        ace_mon,
                        *this->lock_,
                        0);

      TABLE::ITERATOR end_iter = this->table_.end ();
      TABLE::ITERATOR start;

      while ((start = this->table_.begin ()) != end_iter)
        {
          TABLE::ENTRY &ent = (*start);

          ent.item ()->decr_refcount ();
          this->table_.unbind (&ent);
        }
    }

  return 0;
}

int TAO::ObjectKey_Table::init

(

TAO_ORB_Core *

orb

)

Initialize method that sets up the underlying lock and other related stuff.

Create the lock that is needed for internal usage.

Definition at line 51 of file ObjectKey_Table.cpp.

References TAO_Resource_Factory::create_object_key_table_lock(), lock_, and TAO_ORB_Core::resource_factory().

{
  /// Create the lock that is needed for internal usage.
  this->lock_ =
    oc->resource_factory ()->create_object_key_table_lock ();

  return 0;
}

int TAO::ObjectKey_Table::unbind

(

TAO::Refcounted_ObjectKey *&

key

)

Unbind an ObjectKey from the table.

Definition at line 96 of file ObjectKey_Table.cpp.

References ACE_GUARD_RETURN, and unbind().

Referenced by unbind().

{
  ACE_GUARD_RETURN (ACE_Lock,
                    ace_mon,
                    *this->lock_,
                    0);

  // If the refcount has dropped to 1, just go ahead and unbind it
  // from the table.
  if (key_new && key_new->decr_refcount () == 1)
    {
      return this->unbind_i (key_new);
    }

  return 0;
}

int TAO::ObjectKey_Table::unbind_i

(

Refcounted_ObjectKey *&

key

)

[protected]

Implementation for unbind ().

Definition at line 162 of file ObjectKey_Table.cpp.

References unbind_i().

Referenced by unbind_i().

{
  TAO::Refcounted_ObjectKey *tmp = 0;

  if (this->table_.unbind (key_new->object_key (), tmp) != -1)
    {
      // @@ Cant do much if the unbind fails.
      // Remove our refcount on the ObjectKey
      (void) tmp->decr_refcount ();
    }

  return 0;
}

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Member Data Documentation

ACE_Lock* TAO::ObjectKey_Table::lock_ [private]

Lock for the table.

Definition at line 133 of file ObjectKey_Table.h.

Referenced by init(), and ~ObjectKey_Table().

TABLE TAO::ObjectKey_Table::table_ [private]

Table that contains the data.

Definition at line 136 of file ObjectKey_Table.h.

Referenced by bind(), bind_i(), destroy(), and ~ObjectKey_Table().

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

• ObjectKey_Table.h
• ObjectKey_Table.cpp

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