peergroupadv.java

来自「JXTA&#8482 is a set of open, generalize」· Java 代码 · 共 335 行

/*
 * Copyright (c) 2001-2007 Sun Microsystems, Inc.  All rights reserved.
 *  
 *  The Sun Project JXTA(TM) Software License
 *  
 *  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 Sun Microsystems, Inc. for JXTA(TM) technology." 
 *     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 SUN 
 *  MICROSYSTEMS 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.
 *  
 *  JXTA is a registered trademark of Sun Microsystems, Inc. in the United 
 *  States and other countries.
 *  
 *  Please see the license information page at :
 *  <http://www.jxta.org/project/www/license.html> for instructions on use of 
 *  the license in source files.
 *  
 *  ====================================================================
 *  
 *  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. 
 */

package net.jxta.impl.protocol;


import net.jxta.document.Advertisement;
import net.jxta.document.AdvertisementFactory;
import net.jxta.document.Attribute;
import net.jxta.document.Document;
import net.jxta.document.Element;
import net.jxta.document.MimeMediaType;
import net.jxta.document.StructuredDocument;
import net.jxta.document.StructuredDocumentUtils;
import net.jxta.document.TextElement;
import net.jxta.document.XMLElement;
import net.jxta.id.IDFactory;
import net.jxta.logging.Logging;
import net.jxta.peergroup.PeerGroupID;
import net.jxta.platform.ModuleClassID;
import net.jxta.platform.ModuleSpecID;
import net.jxta.protocol.PeerGroupAdvertisement;

import java.net.URI;
import java.net.URISyntaxException;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.logging.Level;
import java.util.logging.Logger;


public class PeerGroupAdv extends PeerGroupAdvertisement {

    /**
     * Log4J Logger
     */
    private static final Logger LOG = Logger.getLogger(PeerGroupAdv.class.getName());

    private static final String nameTag = "Name";
    private static final String gidTag = "GID";
    private static final String descTag = "Desc";
    private static final String msidTag = "MSID";
    private static final String svcTag = "Svc";
    private static final String mcidTag = "MCID";
    private static final String paramTag = "Parm";
    private static final String[] fields = { nameTag, gidTag, descTag, msidTag};

    public static class Instantiator implements AdvertisementFactory.Instantiator {

        /**
         * {@inheritDoc}
         */

        public String getAdvertisementType() {
            return PeerGroupAdv.getAdvertisementType();
        }

        /**
         * {@inheritDoc}
         */
        public Advertisement newInstance() {
            return new PeerGroupAdv();
        }

        /**
         * {@inheritDoc}
         */
        public Advertisement newInstance(net.jxta.document.Element root) {
            return new PeerGroupAdv(root);
        }
    }

    /**
     * Use the Instantiator method to construct Peer Group Advs.
     */
    private PeerGroupAdv() {}

    /**
     * Use the Instantiator method to construct Peer Group Advs.
     *
     * @param root the element
     */
    private PeerGroupAdv(Element root) {
        if (!XMLElement.class.isInstance(root)) {
            throw new IllegalArgumentException(getClass().getName() + " only supports XLMElement");
        }

        XMLElement doc = (XMLElement) root;

        String doctype = doc.getName();

        String typedoctype = "";
        Attribute itsType = doc.getAttribute("type");

        if (null != itsType) {
            typedoctype = itsType.getValue();
        }

        if (!doctype.equals(getAdvertisementType()) && !getAdvertisementType().equals(typedoctype)) {
            throw new IllegalArgumentException(
                    "Could not construct : " + getClass().getName() + "from doc containing a " + doc.getName());
        }

        Enumeration elements = doc.getChildren();

        while (elements.hasMoreElements()) {
            XMLElement elem = (XMLElement) elements.nextElement();

            if (!handleElement(elem)) {
                if (Logging.SHOW_FINE && LOG.isLoggable(Level.FINE)) {
                    LOG.fine("Unhandled Element: " + elem.toString());
                }
            }
        }

        // Sanity Check!!!
        if (null == getPeerGroupID()) {
            throw new IllegalArgumentException("Peer Group Advertisement did not contain a peer group id.");
        }

        if (null == getModuleSpecID()) {
            throw new IllegalArgumentException("Peer Group Advertisement did not contain a module spec id.");
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getAdvType() {
        return getAdvertisementType();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected boolean handleElement(Element raw) {

        if (super.handleElement(raw)) {
            return true;
        }

        XMLElement elem = (XMLElement) raw;

        if (elem.getName().equals(nameTag)) {
            setName(elem.getTextValue());
            return true;
        }

        if (elem.getName().equals(descTag)) {
            setDesc(elem);
            return true;
        }

        if (elem.getName().equals(gidTag)) {
            try {
                URI grID = new URI(elem.getTextValue());

                setPeerGroupID((PeerGroupID) IDFactory.fromURI(grID));
            } catch (URISyntaxException badID) {
                throw new IllegalArgumentException("Bad peer group ID in advertisement: " + elem.getTextValue());
            } catch (ClassCastException badID) {
                throw new IllegalArgumentException("Id is not a group id: " + elem.getTextValue());
            }
            return true;
        }

        if (elem.getName().equals(msidTag)) {
            try {
                URI specID = new URI(elem.getTextValue());

                setModuleSpecID((ModuleSpecID) IDFactory.fromURI(specID));
            } catch (URISyntaxException badID) {
                throw new IllegalArgumentException("Bad msid in advertisement: " + elem.getTextValue());
            } catch (ClassCastException badID) {
                throw new IllegalArgumentException("Id is not a module spec id: " + elem.getTextValue());
            }
            return true;
        }

        if (elem.getName().equals(svcTag)) {
            Enumeration elems = elem.getChildren();
            String classID = null;
            Element param = null;

            while (elems.hasMoreElements()) {
                TextElement e = (TextElement) elems.nextElement();

                if (e.getName().equals(mcidTag)) {
                    classID = e.getTextValue();
                    continue;
                }
                if (e.getName().equals(paramTag)) {
                    param = e;
                }
            }
            if (classID != null && param != null) {
                // Add this param to the table. putServiceParam()
                // clones param into a standalone document automatically.
                // (classID gets cloned too).
                try {
                    putServiceParam(IDFactory.fromURI(new URI(classID)), param);
                } catch (URISyntaxException badID) {
                    throw new IllegalArgumentException("Bad mcid in advertisement: " + elem.getTextValue());
                } catch (ClassCastException badID) {
                    throw new IllegalArgumentException("Id is not a module class id: " + elem.getTextValue());
                }
            }
            return true;
        }

        return false;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Document getDocument(MimeMediaType encodeAs) {
        if (null == getPeerGroupID()) {
            throw new IllegalStateException("Peer Group Advertisement did not contain a peer group id.");
        }

        if (null == getModuleSpecID()) {
            throw new IllegalStateException("Peer Group Advertisement did not contain a module spec id.");
        }

        StructuredDocument adv = (StructuredDocument) super.getDocument(encodeAs);

        Element e;

        e = adv.createElement(gidTag, getPeerGroupID().toString());
        adv.appendChild(e);

        e = adv.createElement(msidTag, getModuleSpecID().toString());
        adv.appendChild(e);

        // name is optional
        if (null != getName()) {
            e = adv.createElement(nameTag, getName());
            adv.appendChild(e);
        }

        // desc is optional
        StructuredDocument desc = getDesc();

        if (desc != null) {
            StructuredDocumentUtils.copyElements(adv, adv, desc);
        }

        // FIXME: this is inefficient - we force our base class to make
        // a deep clone of the table.
        Hashtable serviceParams = getServiceParams();
        Enumeration classIds = serviceParams.keys();

        while (classIds.hasMoreElements()) {
            ModuleClassID classId = (ModuleClassID) classIds.nextElement();

            Element s = adv.createElement(svcTag);

            adv.appendChild(s);

            e = adv.createElement(mcidTag, classId.toString());
            s.appendChild(e);

            e = (Element) serviceParams.get(classId);
            StructuredDocumentUtils.copyElements(adv, s, e, paramTag);

        }
        return adv;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String[] getIndexFields() {
        return fields;
    }
}