groupsearch.java

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/*
*  Copyright (c) 2001 Sun Microsystems, Inc.  All rights
*  reserved.
*
*  Redistribution and use in source and binary forms, with or without
*  modification, are permitted provided that the following conditions
*  are met:
*
*  1. Redistributions of source code must retain the above copyright
*  notice, this list of conditions and the following disclaimer.
*
*  2. Redistributions in binary form must reproduce the above copyright
*  notice, this list of conditions and the following disclaimer in
*  the documentation and/or other materials provided with the
*  distribution.
*
*  3. The end-user documentation included with the redistribution,
*  if any, must include the following acknowledgment:
*  "This product includes software developed by the
*  Sun Microsystems, Inc. for Project JXTA."
*  Alternately, this acknowledgment may appear in the software itself,
*  if and wherever such third-party acknowledgments normally appear.
*
*  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA"
*  must not be used to endorse or promote products derived from this
*  software without prior written permission. For written
*  permission, please contact Project JXTA at http://www.jxta.org.
*
*  5. Products derived from this software may not be called "JXTA",
*  nor may "JXTA" appear in their name, without prior written
*  permission of Sun.
*
*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
*  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
*  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
*  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
*  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
*  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
*  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
*  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
*  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
*  SUCH DAMAGE.
*  ====================================================================
*
*  This software consists of voluntary contributions made by many
*  individuals on behalf of Project JXTA.  For more
*  information on Project JXTA, please see
*  <http://www.jxta.org/>.
*
*  This license is based on the BSD license adopted by the Apache Foundation.
*
*  $Id: GroupSearch.java,v 1.2 2006/05/17 21:02:47 nano Exp $
*/

package net.jxta.myjxta.search;

import net.jxta.discovery.DiscoveryEvent;
import net.jxta.discovery.DiscoveryListener;
import net.jxta.discovery.DiscoveryService;
import net.jxta.myjxta.MyJXTA;
import net.jxta.myjxta.util.Group;
import net.jxta.myjxta.util.objectmodel.GroupNode;
import net.jxta.protocol.DiscoveryResponseMsg;
import net.jxta.protocol.PeerGroupAdvertisement;

import java.io.IOException;
import java.util.Enumeration;

/**
 *
 * @version $Id: GroupSearch.java,v 1.2 2006/05/17 21:02:47 nano Exp $
 *
 * @author james todd [gonzo at jxta dot org]
 */

public class GroupSearch
    extends AbstractSearch
    implements DiscoveryListener {

    /** The name of the attribute we are searching for */
    public static final String ATTRIBUTE_NAME = "Name";

    /** The title of the search */
    private static final String TITLE = "Group Search";

    /** The description of the search */
    private static final String DESCRIPTION = "groups";


    /**
     * Create a new GroupSearch instance 
     * 
     * @param group the group in which this search is done
     * @param myJxta the MyJxta instance for system wide defaults.
     *               The currently selected group in this instance my be different
     *               from group
     */
    public GroupSearch(Group group, MyJXTA myJxta) {
        super(group, myJxta);

        setTitle(TITLE);
    }

    /**
     * Return the  description of the search
     * 
     * @return the description of the search
     */
    public String getSearchDescription() {
        return getDescription(DESCRIPTION);
    }

    /**
     * Start the search for the indicated term
     *
     * @param term the term  to search for
     */
    public void search(String term) {
        setTerm(term);

        String criteria = (term.trim().length() == 0 ||
            term.equals(WILDCARD) ? null : term);

        cancel();
        isRunning(true);

        DiscoveryService discover = getDiscovery();  // this also fixes the group
       
        try {
            process(discover.getLocalAdvertisements(
                DiscoveryService.GROUP,
                criteria != null ? ATTRIBUTE_NAME : null, criteria));
        } catch (IOException ioe) {}

        discover.getRemoteAdvertisements(null, DiscoveryService.GROUP,
            criteria != null ? ATTRIBUTE_NAME : null, criteria,
            REMOTE_THRESHOLD, this);
        
        isRunning(false);
    }

    public void cancel() {
        if (isRunning()) {
            isRunning(false);
            getDiscovery().removeDiscoveryListener(this);

            super.cancel();
        }
    }

    public void discoveryEvent(DiscoveryEvent de) {
        DiscoveryResponseMsg rm = de.getResponse();

        if (rm.getDiscoveryType() == DiscoveryService.GROUP) {
            process(rm.getAdvertisements());
        }
    }

    private void process(Enumeration advertisements) {
        PeerGroupAdvertisement pga = null;
        Object o = null;

        while (advertisements != null &&
               advertisements.hasMoreElements()) {
            o = advertisements.nextElement();

            if (o instanceof PeerGroupAdvertisement) {
                pga = (PeerGroupAdvertisement)o;
                Group go = new Group(myJxta, pga, group);
                add(new GroupNode(go));
            }
        }
    }
}