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// -*- C++ -*-
// $Id$
// ============================================================================
//
// = LIBRARY
// TAO_LoadBalancing
//
// = FILENAME
// ReplicaProxy.h
//
// = AUTHOR
// Ossama Othman <ossama@uci.edu>
//
// ============================================================================
#ifndef TAO_REPLICAPROXY_H
#define TAO_REPLICAPROXY_H
#include "ace/pre.h"
#include "orbsvcs/LoadBalancingS.h"
#include "LoadBalancing_export.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */
#if defined(_MSC_VER)
#if (_MSC_VER >= 1200)
#pragma warning(push)
#endif /* _MSC_VER >= 1200 */
#pragma warning(disable:4250)
#endif /* _MSC_VER */
class TAO_LB_LoadBalancer;
// Forward declaration
class TAO_LoadBalancing_Export TAO_LB_ReplicaProxy :
public virtual POA_LoadBalancing::ReplicaProxy,
public virtual PortableServer::RefCountServantBase
{
friend class TAO_LB_LoadBalancer;
public:
TAO_LB_ReplicaProxy (void);
CORBA::Float current_load (void) const;
// Read the stored load of the Object being load balanced from the
// ReplicaProxy.
CORBA::Object_ptr replica (void);
// Return a reference to the Replica.
virtual void current_load (CORBA::Float load,
CORBA::Environment &ACE_TRY_ENV)
ACE_THROW_SPEC ((CORBA::SystemException));
// Send the value of the current load on the Object being load
// balanced, where the definition of "load" is load balancing
// algorithm specific.
// @@ Ossama: i had to implement dampening mechanisms in the load,
// otherwise the spikes where killing me, but i'm not sure if that
// should be implemented in the client or the server.
// @@ I think that the 'Right Thing' is to have the client send
// 'instantaneous load' and get the load balancing service to do the
// dampening... that way we can modify the algorithm in the server,
// without affecting the client, or detect rapid raises in load and
// react proactively to those...
virtual void disconnect (CORBA::Environment &ACE_TRY_ENV)
ACE_THROW_SPEC ((LoadBalancing::ReplicaProxy::NotConnected,
CORBA::SystemException));
// Send a request to disconnect from the LoadBalancer.
// @@ Ossama: could you please fix the mess i left here? it is my
// fault, but i was running short on time.
int has_high_load_;
// Has the high load advisory been sent
// @@ Ossama: i added this flag to avoid multiple nomimal load
// advisories and high load advisories to be sent.
LoadBalancing::ReplicaControl_var control_;
// Reference to the ReplicaControl.
private:
~TAO_LB_ReplicaProxy (void);
// Destructor is private to ensure that this object is allocated on
// the heap.
void connect (TAO_LB_LoadBalancer *balancer,
LoadBalancing::ReplicaControl_ptr control,
CORBA::Object_ptr replica,
CORBA::Environment &ACE_TRY_ENV)
ACE_THROW_SPEC ((LoadBalancing::ReplicaProxy::NilControl,
LoadBalancing::ReplicaProxy::NilReplica,
CORBA::SystemException));
// Register the ReplicaControl and the Object being load balanced
// with the ReplicaProxy.
private:
CORBA::Object_var replica_;
// Reference to the Object being load balanced.
TAO_LB_LoadBalancer *balancer_;
// Pointer to the Load Balancer this ReplicaProxy is registered
// with.
CORBA::Float current_load_;
// The current load on the Object being load balanced.
CORBA::Boolean connected_;
// 1 == currently connected to load balancer
// 0 == currently disconnected from load balancer
};
#if defined(__ACE_INLINE__)
#include "ReplicaProxy.i"
#endif /* __ACE_INLINE__ */
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
#pragma warning(pop)
#endif /* _MSC_VER */
#include "ace/post.h"
#endif /* TAO_REPLICAPROXY_H */
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