regionalgis.java

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     * @post $none
     */
    protected void processGlobalResourceARList(Sim_event ev)
    {
        LinkedList regionalList = null;   // regional GIS list
        int eventTag = AbstractGIS.GIS_INQUIRY_RESOURCE_AR_LIST;
        boolean result = false;

        // for a first time request, it needs to call the system GIS first,
        // then asks each regional GIS for its resource IDs.
        if (globalResARList_ == null)
        {
            // get regional GIS list from system GIS first
            regionalList = requestFromSystemGIS();

            // ask a resource list from each regional GIS
            result = getListFromOtherRegional(regionalList, eventTag);
            if (result == true)
            {
                globalResARList_ = new ArrayList();  // storing global AR
                numAR_ = regionalList.size() - 1;    // excluding GIS itself

                // then store the user ID
                Integer id = (Integer) ev.get_data();
                userARList_ = new ArrayList();
                userARList_.add(id);
                return;     // then exit
            }
        }

        // cache the request and store the user ID if it is already sent
        if (numAR_ > 0 && userARList_ != null && userARList_.size() > 0)
        {
            Integer id = (Integer) ev.get_data();
            userARList_.add(id);
            return;     // then exit
        }

        result = sendListToSender(ev, globalResARList_);
        if (result == false)
        {
            System.out.println(super.get_name() +
                ".processGlobalResourceARList(): Warning - can't send a " +
                "resource AR list to sender.");
        }
    }

    /**
     * Process an incoming request from users about getting a list of resource
     * IDs, that are registered in other regional GIS entities.
     *
     * @param ev  a Sim_event object (or an incoming event or request)
     * @pre ev != null
     * @post $none
     */
    protected void processGlobalResourceList(Sim_event ev)
    {
        /***
        NOTE: possible cases are
        - if there is only 1 local GIS and no other regional GISes
        - if there is only 1 user queries for this
        - if there are 2 or more users query at different time
        ****/

        LinkedList regionalList = null;   // regional GIS list
        int eventTag = AbstractGIS.GIS_INQUIRY_RESOURCE_LIST;
        boolean result = false;

        // for a first time request, it needs to call the system GIS first,
        // then asks each regional GIS for its resource IDs.
        if (globalResList_ == null)
        {
            // get regional GIS list from system GIS first
            regionalList = requestFromSystemGIS();

            // ask a resource list from each regional GIS
            result = getListFromOtherRegional(regionalList, eventTag);
            if (result == true)
            {
                globalResList_ = new ArrayList();    // storing global resources
                numRes_ = regionalList.size() - 1;   // excluding itself

                // then store the user ID
                Integer id = (Integer) ev.get_data();
                userList_ = new ArrayList();
                userList_.add(id);
                return;     // then exit
            }
        }

        // cache the request and store the user ID if it is already sent
        if (numRes_ > 0 && userList_ != null && userList_.size() > 0)
        {
            Integer id = (Integer) ev.get_data();
            userList_.add(id);
            return;     // then exit
        }

        // send the result back to sender, where the list could be empty
        result = sendListToSender(ev, globalResList_);
        if (result == false)
        {
            System.out.println(super.get_name() +
                ".processGlobalResourceList(): Warning - can't send a " +
                "resource list to sender.");
        }
    }

    /**
     * Get a list of IDs specified in the eventTag from other regional GIS
     * @param regionalList  a list of regional GIS IDs
     * @param eventTag      an event tag or type of request
     * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
     * @pre regionalList != null
     * @post $none
     */
    protected boolean getListFromOtherRegional(List regionalList, int eventTag)
    {
        // check for input first
        if (regionalList == null || regionalList.size() == 0) {
            return false;
        }

        // a loop to ask each regional GIS for its resource IDs
        Iterator it = regionalList.iterator();
        while ( it.hasNext() )
        {
            Integer obj = (Integer) it.next();

            // can not send to itself
            if (obj.equals(myID_) == true) {
                continue;
            }

            // send a request to a regional GIS
            super.send( super.output, 0.0, eventTag,
                        new IO_data(myID_, Link.DEFAULT_MTU, obj.intValue()) );

            /******   // Debug info
            System.out.println(super.get_name()+".getListFromOtherRegional(): "
                    + "query to " + GridSim.getEntityName( obj.intValue() )
                    + ", tag = " + eventTag);
            ******/
        }

        return true;
    }

    /**
     * Asks from {@link gridsim.GridInformationService} or system GIS about
     * a list of regional GIS entity ID.
     * @return a list of regional GIS entity ID
     * @pre $none
     * @post $none
     */
    protected LinkedList requestFromSystemGIS()
    {
        // get the regional GIS list from local cache
        if (regionalList_ != null) {
            return regionalList_;
        }
        else {
            regionalList_ = new LinkedList();
        }

        // for the first time, ask the regional GIS list from system GIS
        int eventTag = GridSimTags.REQUEST_REGIONAL_GIS;
        boolean result = requestFromSystemGIS(eventTag, regionalList_);

        return regionalList_;
    }

    /**
     * Asks from {@link gridsim.GridInformationService} or system GIS about
     * a specific event or request.
     *
     * @param eventTag  an event tag or type of request
     * @param list      a list storing the results
     * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
     * @pre list != null
     * @post $none
     */
    protected boolean requestFromSystemGIS(int eventTag, List list)
    {
        boolean result = false;
        if (list == null) {
            return result;
        }

        // send a request to system GIS for a list of other regional GIS
        super.send( super.output, 0.0, eventTag,
                    new IO_data(myID_, Link.DEFAULT_MTU, super.systemGIS_) );

        // waiting for a response from system GIS
        Sim_type_p tag = new Sim_type_p(eventTag);

        // only look for this type of ack
        Sim_event ev = new Sim_event();
        super.sim_get_next(tag, ev);

        try
        {
            List tempList = (List) ev.get_data();
            list.addAll(tempList);
            result = true;
        }
        catch (Exception e)
        {
            result = false;
            System.out.println(super.get_name() +
                    ".requestFromSystemGIS(): Exception error.");
        }

        return result;
    }

    /**
     * Sends a given list to sender
     * @param ev    a Sim_event object
     * @param list  a list to be sent to
     * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
     */
    private boolean sendListToSender(Sim_event ev, List list)
    {
        if (ev == null) {
            return false;
        }

        boolean result = false;
        Object obj = ev.get_data();
        if (obj instanceof Integer)
        {
            Integer id = (Integer) obj;
            result = sendListToSender(id.intValue(), ev.get_tag(), list);
        }

        return result;
    }

    /**
     * Sends a list to sender
     * @param senderID  the sender ID
     * @param tag       an event tag
     * @param list      a list to be sent to
     * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
     * @pre senderID != -1
     * @post $none
     */
    protected boolean sendListToSender(int senderID, int tag, List list)
    {
        if (senderID < 0) {
            return false;
        }

        int length = 0;
        if (list == null || list.size() == 0) {
            length = 1;
        }
        else {
            length = list.size();
        }

        /******   // DEBUG info
        System.out.println(super.get_name()+".sendListToSender(): send list = "
            + list + ", tag = " + tag + " to "+GridSim.getEntityName(senderID));
        System.out.println();
        ******/

        // Send the event or message
        super.send( super.output, 0.0, tag,
                    new IO_data(list, Link.DEFAULT_MTU*length, senderID) );

        return true;
    }

    /**
     * Process an incoming request about getting a list of resource IDs
     * that are registered to this regional GIS entity.
     *
     * @param ev  a Sim_event object (or an incoming event or request)
     * @pre ev != null
     * @post $none
     */
    protected void processResourceList(Sim_event ev)
    {
        /*****   // Debug info
        Integer id = (Integer) ev.get_data();
        System.out.println(super.get_name() + ".processResourceList():" +
            " request from " + GridSim.getEntityName(id.intValue()) +
            " for list = " + resList_ + " tag = " + ev.get_tag());
        *******/

        boolean result = sendListToSender(ev, resList_);
        if (result == false)
        {
            System.out.println(super.get_name() +
                ".processResourceList(): Warning - unable to send a list " +
                "of resource IDs to sender.");
        }
    }

    /**
     * Process an incoming request about getting a list of resource IDs
     * supporting Advanced Reservation that are registered to this regional GIS
     * entity.
     *
     * @param ev  a Sim_event object (or an incoming event or request)
     * @pre ev != null
     * @post $none
     */
    protected void processResourceARList(Sim_event ev)
    {
        boolean result = sendListToSender(ev, arList_);
        if (result == false)
        {
            System.out.println(super.get_name() +
                ".processResourceARList(): Warning - unable to send a list " +
                "of resource IDs to sender.");
        }
    }

    /**
     * Registers other information to {@link gridsim.GridInformationService} or
     * system GIS.<br>
     * NOTE: This method can be overridden by its subclasses, provided
     *       that they call this method first. This is required, just in case
     *       this method is not empty.
     * @pre $none
     * @post $none
     */
    protected void registerOtherEntity() {
        // empty
    }


    /**
     * Informs the registered entities regarding to the end of a simulation.<br>
     * NOTE: This method can be overridden by its subclasses, provided
     *       that they call this method first. This is required, just in case
     *       this method is not empty.
     * @pre $none
     * @post $none
     */
    protected void processEndSimulation()
    {
        resList_.clear();
        arList_.clear();

        if (regionalList_ != null) {
            regionalList_.clear();
        }

        if (globalResList_ != null) {
            globalResList_.clear();
        }

        if (globalResARList_ != null) {
            globalResARList_.clear();
        }

        if (userList_ != null) {
            userList_.clear();
        }

        if (userARList_ != null) {
            userARList_.clear();
        }
    }

} // end class