topregionalrc.java

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        super.send(super.output, 0, DataGridTags.CTLG_ADD_MASTER_RESULT,
            new IO_data(data, DataGridTags.PKT_SIZE, resourceID.intValue()) );
    }

    /**
     * Deletes a master file from the catalogue. A method very
     * similar to the {@link #processDeleteReplica(Sim_event)}. The
     * difference is that the master file is never deleted if there are more
     * than one entry in the catalogue, i.e. replicas of this file still exist.
     * Before the master file can be deleted all the replicas need to be deleted
     * first.
     *
     * @param ev    a Sim_event object
     */
    private void processDeleteMaster(Sim_event ev)
    {
        if (ev == null) {
            return;
        }

        Object[] obj = (Object[]) ev.get_data();
        if (obj == null)
        {
            System.out.println(super.get_name() +
                    ".processDeleteMaster(): master file name is null");
            return;
        }

        String name = (String) obj[0];      // get file name
        Integer resID = (Integer) obj[1];   // get resource id

        int msg = DataGridTags.CTLG_DELETE_MASTER_SUCCESSFUL;
        try
        {
            ArrayList list = (ArrayList) catalogueHash_.get(name);
            if (list.size() != 1) {
                msg = DataGridTags.CTLG_DELETE_MASTER_REPLICAS_EXIST;
            }
            else if (list.remove(resID) == false) {
                msg = DataGridTags.CTLG_DELETE_MASTER_DOESNT_EXIST;
            }
            else {
                catalogueHash_.remove(name);    // remove from the catalogue
                attrHash_.remove(name);
            }
        }
        catch (Exception e) {
            msg = DataGridTags.CTLG_DELETE_MASTER_ERROR;
        }

        sendMessage(name, DataGridTags.CTLG_DELETE_MASTER_RESULT, msg,
                    resID.intValue() );
    }



    //-----------------PROCESS USER REQUESTS-------------------------------
    /**
     * Processes the request for a file attribute. If the Replica Catalogue
     * contains the {@link gridsim.datagrid.FileAttribute} of the file
     * then it is sent to the requester.
     *
     * @param ev    a Sim_event object
     */
    private void processFileAttrRequest(Sim_event ev)
    {
        if (ev == null) {
            return;
        }

        int requesterID = -1;
        int size = 0;
        FileAttribute attr = null;

        try
        {
            Object[] obj = (Object[]) ev.get_data();
            if (obj == null) {
                return;
            }

            String name = (String) obj[0];          // get file name
            Integer senderID = (Integer) obj[1];    // get sender id
            requesterID = senderID.intValue();

            // get the file attribute of a given filename
            attr = (FileAttribute) attrHash_.get(name);
            if (attr != null) {
                size = attr.getAttributeSize();
            }
            else
            {
                size = DataGridTags.PKT_SIZE;
                attr = null;
            }
        }
        catch (Exception e)
        {
            attr = null;
            size = DataGridTags.PKT_SIZE;
        }

        // send back to requester
        if (requesterID != -1)
        {
            super.send(super.output, 0, DataGridTags.CTLG_FILE_ATTR_DELIVERY,
                       new IO_data(attr, size, requesterID) );
        }
    }

    /**
     * Processes a request for filtering the files. A user sends a
     * {@link gridsim.datagrid.filter.Filter} to the Replica Catalogue.
     * Only the top level Replica Catalogue runs the filter accross the list
     * of all {@link gridsim.datagrid.FileAttribute}
     * All the attributes that are filtered out are sent back to the requester.
     *
     * @param ev    a Sim_event object
     */
    private void processFilterFiles(Sim_event ev)
    {
        if (ev == null) {
            return;
        }

        Object[] data = (Object[]) ev.get_data();
        if (data == null) {
            return;
        }

        Filter f = (Filter) data[0];
        int destination = ((Integer) data[1]).intValue();

        ArrayList list = new ArrayList();
        int size = 0;

        Enumeration attributes = attrHash_.elements();
        while ( attributes.hasMoreElements() )
        {
            FileAttribute attrTemp = (FileAttribute) attributes.nextElement();
            if (f.match(attrTemp) == true)
            {
                list.add(attrTemp);     // add this attribute into the list
                size += attrTemp.getAttributeSize();
            }
        }

        // sends back the result to the sender
        super.send(super.output, 0, DataGridTags.CTLG_FILTER_DELIVERY,
                   new IO_data(list, size, destination) );
    }

    /**
     * Processes the request for a file location. If the catalogue contains the
     * file name, the first location of that file is returned back to the user.
     * If there is no enty for the file name in the catalogue and this is not
     * the top Replica Catalogue, the request is forwarded to the higher level
     * catalogue.
     *
     * @param ev    a Sim_event object
     */
    private void processGetReplica(Sim_event ev)
    {
        if (ev == null) {
            return;
        }

        Object[] data = (Object[]) ev.get_data();
        if (data == null) {
            return;
        }

        String filename = (String) data[0];         // get file name
        Integer sender = (Integer) data[1];         // get sender id

        // creates an object that contains the required information
        Object[] dataTemp = new Object[3];
        dataTemp[0] = filename;

        ArrayList list = (ArrayList) catalogueHash_.get(filename);
        if (list != null) {
            dataTemp[1] = (Integer) list.get(0);
        } else {
            dataTemp[1] = new Integer(-1);
        }

        // sends back the result to sender
        super.send(super.output, 0, DataGridTags.CTLG_REPLICA_DELIVERY,
            new IO_data(dataTemp, DataGridTags.PKT_SIZE, sender.intValue()) );
    }

    /**
     * Sends the list of file replica locations that are registered to this RC.
     * @param ev    a Sim_event object
     */
    private void processGetLocalReplicaList(Sim_event ev)
    {
        if (ev == null) {
            return;
        }

        Object[] data = (Object[]) ev.get_data();
        if (data == null) {
            return;
        }

        String filename = (String) data[0];         // get file name
        Integer sender = (Integer) data[1];         // get sender id

        // creates an object that contains the required information
        Object[] dataTemp = new Object[2];
        dataTemp[0] = filename;
        dataTemp[1] = (ArrayList) catalogueHash_.get(filename);

        // sends back the result to sender
        super.send(super.output, 0, DataGridTags.CTLG_REPLICA_LIST_DELIVERY,
            new IO_data(dataTemp, DataGridTags.PKT_SIZE, sender.intValue()) );
    }

    /**
     * Sends a list of resource IDs for the location of replicas
     * @param ev    a Sim_event object
     */
    private void processGetReplicaList(Sim_event ev) {
            processGetLocalReplicaList(ev);
    }


    //  -----------------ADDITIONAL METHODS------------

    /**
     * Creates a unique ID of a file. This method is used only on the top level
     * Replica Catalogue, since it is resposible for generating uniqued IDs.
     *
     * @return a unique ID
     */
    private int createUniqueID(String currentFileName)
    {
        lastUniqueID++;
        //test if the new id would create a clash
        ArrayList list = (ArrayList) catalogueHash_.get(currentFileName+lastUniqueID);
        while(list!=null){
            //if it creates a clash, try using a greater ID
            lastUniqueID++;
            list = (ArrayList) catalogueHash_.get(currentFileName+lastUniqueID);
        }
        return lastUniqueID;
    }

    /**
     * Sends a message as a result of adding or deleting a file. <br>
     * <b>Example: </b>the file of the operation is <i>file12 </i>, the event to
     * be sent is <i>CTLG_DELETE_REPLICA_RESULT </i> and the message to be sent
     * is <i>CTLG_DELETE_SUCCESFUL </i>.
     *
     * @param fileName  the name of the file
     * @param event     the event to be sent
     * @param msg       the message to be sent
     * @param dest      the destination of the message
     */
    private void sendMessage(String fileName, int event, int msg, int dest)
    {
        Object pack[] = new Object[2];
        pack[0] = fileName;
        pack[1] = new Integer(msg);

        super.send(super.output, GridSimTags.SCHEDULE_NOW, event,
                   new IO_data(pack, DataGridTags.PKT_SIZE, dest));
    }

    /**
     * Registers other information to a GIS entity -- THIS METHOD IS EMPTY
     */
    protected void registerOtherEntity() {
        // empty ...
    }

    /**
     * Performs last activities before the end of a simulation -- THIS
     * METHOD IS EMPTY
     */
    protected void processEndSimulation() {
        // empty ...
    }

    /**
     * Register a file which is already stored in a resource <b>before</b> the
     * start of simulation. <br>
     * NOTE: A unique id of this file IS NOT available
     *
     * @param fAttr     a FileAttribute object
     * @param sourceID  the entity ID that stores this file
     * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
     */
    public boolean registerOriginalFile(FileAttribute fAttr, int sourceID)
    {
        if (fAttr == null || sourceID == -1) {
            return false;
        }

        ArrayList list = (ArrayList) catalogueHash_.get( fAttr.getName() );
        if (list != null) {
            list.add( new Integer(sourceID) );
        }
        else {
            list = new ArrayList();
            list.add( new Integer(sourceID) );

            catalogueHash_.put(fAttr.getName(), list);
            attrHash_.put(fAttr.getName(), fAttr);
        }
        return true;
    }

} // end class