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// -*- C++ -*-
//=============================================================================
/**
* @file LB_Redirect_Table.h
*
* $Id$
*
* @author Ossama Othman <ossama@uci.edu>
*/
//=============================================================================
#ifndef TAO_LB_REDIRECT_TABLE_H
#define TAO_LB_REDIRECT_TABLE_H
#include "ace/pre.h"
#include "tao/corbafwd.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */
#include "ace/Synch.h"
#include "ace/Hash_Map_Manager_T.h"
#include "ace/Functor.h"
#include "tao/PortableInterceptorC.h"
/**
* @class TAO_LB_Redirect_Table
*
* @brief Maintain a table of "redirects" corresponding to a target
* with the given RepositoryId.
*
* If a table entry for the given RepositoryId exists, then the load
* monitor will redirect the client request to the target pointed to
* by the object reference in that entry.
*
* It is necessary to maintain a redirect table since the load
* balancer determines which object group to select a replica from by
* examining the target's object ID. As such a request cannot simply
* be forwarded back to the load balancer without knowing what its
* intended target (i.e. object group) is. This table keeps track of
* the object group reference to which a replica of a given type
* belongs.
*/
class TAO_LB_Redirect_Table
{
public:
typedef ACE_Hash_Map_Manager_Ex<const char *, CORBA::Object_ptr, ACE_Hash<const char *>, ACE_Equal_To<const char *>, ACE_Null_Mutex> Table;
/// Constructor
TAO_LB_Redirect_Table (void);
/// Destructor
~TAO_LB_Redirect_Table (void);
/// Register an object reference with the table, and map the given
/// ID to it.
void register_redirect (const char * type_id,
CORBA::Object_ptr redirect_to,
CORBA::Environment &ACE_TRY_ENV);
/// Remove the redirect associated with the given RepositoryId.
void remove_redirect (const char *type_id,
CORBA::Environment &ACE_TRY_ENV);
/// Check if a redirect exists for the current target. If so, then
/// perform the request redirection by throwing a
/// PortableInterceptor::ForwardRequest exception.
void find_redirect (PortableInterceptor::ServerRequestInfo_ptr ri,
CORBA::Environment &ACE_TRY_ENV);
/// Reclaim the resources held by this table (deallocate strings,
/// release object references, etc).
void destroy (void);
private:
/// Helper method that binds the redirect to the given RepositoryId.
int bind (const char *type_id, CORBA::Object_ptr redirect_to);
private:
/// Prevent copying
ACE_UNIMPLEMENTED_FUNC (TAO_LB_Redirect_Table (const TAO_LB_Redirect_Table &))
ACE_UNIMPLEMENTED_FUNC (void operator= (const TAO_LB_Redirect_Table &))
private:
/// The implementation.
Table table_;
};
#include "ace/post.h"
#endif /* TAO_LB_REDIRECT_TABLE_H */
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