FeedLink.h

Go to the documentation of this file.

// Copyright Onix Solutions Limited [OnixS]. All rights reserved.
//
// This software owned by Onix Solutions Limited [OnixS] and is 
// protected by copyright law and international copyright treaties.
//
// Access to and use of the software is governed by the terms of the applicable 
// OnixS Software Services Agreement (the Agreement) and Customer end user license 
// agreements granting a non-assignable, non-transferable and non-exclusive license 
// to use the software for it's own data processing purposes under the terms defined 
// in the Agreement.
//
// Except as otherwise granted within the terms of the Agreement, copying or 
// reproduction of any part of this source code or associated reference material 
// to any other location for further reproduction or redistribution, and any 
// amendments to this copyright notice, are expressly prohibited.
//
// Any reproduction or redistribution for sale or hiring of the Software not in 
// accordance with the terms of the Agreement is a violation of copyright law.
//

#pragma once

#include <string>

#include <OnixS/CME/ConflatedUDP/Integral.h>

ONIXS_CONFLATEDUDP_NAMESPACE_BEGIN

ONIXS_CONFLATEDUDP_LTWT_CLASS_DECL(NetFeed);

/// Abstraction of a link used by the NetFeed 
/// instances to cover transportation layer. 
///
/// The actual implementations are provided by 
/// a particular feed engine, whereas the NetFeed 
/// class interacts with the feed engine through 
/// the given abstraction. 
ONIXS_CONFLATEDUDP_EXPORTED_CLASS NetFeedLink
{
    NetFeedLink(
        const NetFeedLink&);
    
    NetFeedLink& 
    operator =(
        const NetFeedLink&);

protected:
    /// Instances are constructed through descendants. 
    NetFeedLink()
    {
    }

    /// Instances aren't destructed in a regular way. 
    /// The 'release()' member serves for that purpose. 
    virtual ~NetFeedLink()
    {
    }

public:
    /// Establishes connection for the given feed. 
    /// 
    /// The timeout parameter specifies amount of time 
    /// allocated for the link to get into connected/linked 
    /// state. The string parameter is used by the feed 
    /// engine to report on non-critical issues which may 
    /// take place while establishing communication link. 
    virtual 
    void 
    link(
        const NetFeed&, 
        UInt32, 
        std::string&) = 0;

    /// Closes communication link for the given feed. 
    virtual 
    void 
    unlink(
        const NetFeed&) = 0;

    /// Sends the given message to the counterpart. 
    /// 
    /// The given member is invoked by Handler only for the 
    /// feeds assuming bi-directional communication like the 
    /// historical ones. Multicast links aren't supposed to 
    /// provide the given functionality and thus may raise 
    /// an exception. 
    virtual 
    void 
    send(
        const NetFeed&, 
        const void*, 
        size_t,
        UInt32) = 0;

    /// Releases the link used by the given feed. 
    /// Once invoked, no other members are invoked 
    /// afterwards any more. 
    virtual
    void
    release(
        const NetFeed&) = 0;
};

ONIXS_CONFLATEDUDP_NAMESPACE_END