datagriduser.java

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/*
 * Title:        GridSim Toolkit
 * Description:  GridSim (Grid Simulation) Toolkit for Modeling and Simulation
 *               of Parallel and Distributed Systems such as Clusters and Grids
 * Licence:      GPL - http://www.gnu.org/copyleft/gpl.html
 */
package gridsim.datagrid;

import eduni.simjava.*;
import gridsim.datagrid.index.*;
import gridsim.*;
import gridsim.net.Link;
import gridsim.datagrid.filter.*;
import java.util.*;


/**
 * A class for representing a user in a Data Grid environment
 * @author  Uros Cibej and Anthony Sulistio
 * @since   GridSim Toolkit 4.0
 */
public class DataGridUser extends GridUser {

    private String rcName_;     // replica catalogue name
    private int rcID_;          // replica catalogue ID
    private Integer myID_;      // this entity ID


    /**
     * Creates a new DataGrid user.<br>
     * NOTE: When using this constructor, do not forget to set
     * the regional GIS name and the Replica Catalogue name for this entity.
     * @param   name    the user name
     * @param   link    a network link to connect this user to a network
     * @throws  Exception       happens if one of the inputs is empty or null
     * @see gridsim.GridUser#setRegionalGIS(String)
     * @see gridsim.GridUser#setRegionalGIS(AbstractGIS)
     * @see gridsim.datagrid.DataGridUser#setReplicaCatalogue(String)
     * @see gridsim.datagrid.DataGridUser#setReplicaCatalogue(AbstractRC)
     */
    public DataGridUser(String name, Link link) throws Exception
    {
        super(name, link);
        init();
    }

    /**
     * Creates a new DataGrid user.<br>
     * NOTE: When using this constructor, do not forget to set
     * the Replica Catalogue name for this entity.
     * @param   name    the user name
     * @param   link    a network link to connect this user to a network
     * @param   regionalGIS     a Regional GIS name
     * @throws  Exception       happens if one of the inputs is empty or null
     * @see gridsim.datagrid.DataGridUser#setReplicaCatalogue(String)
     * @see gridsim.datagrid.DataGridUser#setReplicaCatalogue(AbstractRC)
     */
    public DataGridUser(String name, Link link, String regionalGIS)
                        throws Exception
    {
        super(name, link, regionalGIS);
        init();
    }

    /** Initializes all the variables */
    private void init()
    {
        rcName_ = null;
        rcID_ = -1;
        myID_ = new Integer( super.get_id() );
    }

    /**
     * Creates a new DataGrid user
     * @param   name    the user name
     * @param   link    a network link to connect this user to a network
     * @param   rcName  a Replica Catalogue name
     * @param   regionalGIS     a Regional GIS name
     * @throws  Exception       happens if one of the inputs is empty or null
     */
    public DataGridUser(String name, Link link, String rcName,
                        String regionalGIS) throws Exception
    {
        super(name, link, regionalGIS);
        rcID_ = GridSim.getEntityId(rcName);
        if (rcName == null || rcID_ == -1) {
            throw new Exception(name + ": Error - invalid RC name");
        }

        rcName_ = rcName;
        myID_ = new Integer( super.get_id() );
    }

    /**
     * Sets a Replica Catalogue name for this user
     * (the old name will be overwritten).
     * @param   rcName  a Replica Catalogue name
     * @return  <tt>true</tt> if successful, <tt>false</tt> otherwise
     */
    public boolean setReplicaCatalogue(String rcName)
    {
        int id = GridSim.getEntityId(rcName);
        if (rcName == null || id == -1) {
            return false;
        }
        rcName_ = rcName;
        rcID_ = id;
        return true;
    }

    /**
     * Sets a Replica Catalogue name for this user
     * (the old name will be overwritten).
     * @param   rc  a Replica Catalogue object
     * @return  <tt>true</tt> if successful, <tt>false</tt> otherwise
     */
    public boolean setReplicaCatalogue(AbstractRC rc)
    {
        if (rc == null) {
            return false;
        }
        return setReplicaCatalogue( rc.get_name() );
    }

    /**
     * Checks whether a Replica Catalogue entity has been allocated to
     * this user or not
     * @return  <tt>true</tt> if the entity has been set,
     *          <tt>false</tt> otherwise
     */
    private boolean checkRC()
    {
        // if no RC entity exists
        boolean result = true;
        if (rcID_ == -1)
        {
            // use the default RC name
            rcID_ = GridSim.getEntityId(TopRegionalRC.DEFAULT_NAME);
            rcName_ = TopRegionalRC.DEFAULT_NAME;

            // If the default RC entity doesn't exist
            if (rcID_ == -1)
            {
                result = false;
                rcName_ = null;     // change the RC name to null
                System.out.println(super.get_name() +
                    ": Error - no TopRegionalRC entity exists.");
            }
        }

        return result;
    }

    /**
     * Gets a Replica Catalogue name
     * @return  a Replica Catalogue name or <tt>null</tt> if it does not exist
     */
    public String getReplicaCatalogueName()
    {
        checkRC();
        return rcName_;
    }

    /**
     * Gets a Replica Catalogue id
     * @return  a Replica Catalogue id or <tt>-1</tt> if it does not exist
     */
    public int getReplicaCatalogueID()
    {
        checkRC();
        return rcID_;
    }

    /**
     * Gets a list of local Replica Catalogue (RC) IDs from a regional
     * GIS entity
     * @return a list of local RC IDs in <tt>Integer</tt> object
     *         or <tt>null</tt> if RCs do not exist.
     */
    public Object[] getLocalRCList() {
        return super.getList(DataGridTags.INQUIRY_LOCAL_RC_LIST);
    }

    /**
     * Gets a list of global Replica Catalogue (RC) IDs.
     * Global RC means a RC that is registered to other
     * regional GIS entities.
     * @return a list of global RC IDs in <tt>Integer</tt> object
     *         or <tt>null</tt> if RCs do not exist.
     */
    public Object[] getGlobalRCList() {
        return super.getList(DataGridTags.INQUIRY_GLOBAL_RC_LIST);
    }

    /**
     * Gets the first resource ID that has the given logical file name (lfn).
     * <br>NOTE: The rest of resource IDs are ignored. If you want to know
     *           all the resource IDs, then
     *           use {@link #getReplicaLocationList(String)} method instead.
     * In addition, this method only contacts the given/chosen RC entity, not
     * all RCs.
     * @param lfn   a logical file name
     * @return a resource ID or <tt>-1</tt> if not found
     */
    public int getReplicaLocation(String lfn)
    {
        if (lfn == null) {
            return -1;
        }

        int resourceID = -1;
        int eventTag = DataGridTags.CTLG_GET_REPLICA;   // set tag name

        // consult with the RC first
        int rcID = getReplicaCatalogueID();
        if (rcID == -1) {
            return -1;
        }

        // sends a request to this RC
        sendEvent(eventTag, lfn, rcID);

        // waiting for a response from the RC
        Sim_type_p tag = new Sim_type_p(DataGridTags.CTLG_REPLICA_DELIVERY);

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

        try
        {
            Object[] data = (Object[]) ev.get_data();   // get the data
            Integer resID = (Integer) data[1];          // get the resource ID
            if (resID != null) {
                resourceID = resID.intValue();
            }
        }
        catch (Exception e)
        {
            resourceID = -1;
            System.out.println(super.get_name()
                    + ".getReplicaLocation(): Exception");
        }

        return resourceID;
    }

    /**
     * Gets a list of resource IDs that store the given logical file name (lfn).
     * <br>NOTE: This method only contacts the given/chosen RC entity, not
     * all RCs.
     * @param lfn   a logical file name
     * @return a list of resource IDs or <tt>null</tt> if not found
     */
    public List getReplicaLocationList(String lfn)
    {
        int rcID = getReplicaCatalogueID();
        return getReplicaLocationList(lfn, rcID);
    }

    /**
     * Gets a list of resource IDs that store the given logical file name (lfn).
     * <br>NOTE: This method only contacts the given/chosen RC entity, not
     * all RCs.
     * @param lfn   a logical file name
     * @param rcID  a RC entity ID
     * @return a list of resource IDs or <tt>null</tt> if not found
     */
    public List getReplicaLocationList(String lfn, int rcID)
    {
        if (lfn == null || rcID == -1) {
            return null;
        }

        // send the event to the RC entity
        int eventTag = DataGridTags.CTLG_GET_REPLICA_LIST;
        sendEvent(eventTag, lfn, rcID);

        // waiting for a response from the RC
        Sim_type_p tag =new Sim_type_p(DataGridTags.CTLG_REPLICA_LIST_DELIVERY);

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

        List resList = null;      // a list of resource IDs storing lfn
        try
        {
            Object[] data = (Object[]) ev.get_data();  // get the data
            resList = (List) data[1];                  // get the resource list
        }
        catch (Exception e)
        {
            resList = null;
            System.out.println(super.get_name()
                    + ".getReplicaLocationList(): Exception.");
        }

        return resList;
    }

    /**
     * Gets an attribute file for a given logical file name (lfn)
     * @param   lfn     a logical file name
     * @return  a FileAttribute object or <tt>null</tt> if not found
     */
    public FileAttribute getFileAttribute(String lfn)
    {
        // check first
        int rcID = getReplicaCatalogueID();
        if (rcID == -1 || lfn == null) {
            return null;
        }

        int eventTag = DataGridTags.CTLG_GET_FILE_ATTR;
        FileAttribute fAttr = null;

        // sends a request to this RC
        sendEvent(eventTag, lfn, rcID);

        // waiting for a response from the RC
        Sim_type_p tag = new Sim_type_p(DataGridTags.CTLG_FILE_ATTR_DELIVERY);

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

        try {
            fAttr = (FileAttribute) ev.get_data();
        }
        catch (Exception e)
        {
            fAttr = null;
            System.out.println(super.get_name()