nonemembershipservice.java

jxta平台的开发包

/*
 * 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 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.
 * ====================================================================
 *
 * 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: NoneMembershipService.java,v 1.5 2004/09/28 00:09:27 bondolo Exp $
 */

package net.jxta.impl.membership.none;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.net.URI;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;

import java.net.URISyntaxException;

import org.apache.log4j.Logger;
import org.apache.log4j.Level;

import net.jxta.credential.AuthenticationCredential;
import net.jxta.credential.Credential;
import net.jxta.credential.CredentialPCLSupport;
import net.jxta.document.Attribute;
import net.jxta.document.Attributable;
import net.jxta.document.Advertisement;
import net.jxta.document.Element;
import net.jxta.document.MimeMediaType;
import net.jxta.document.StructuredDocument;
import net.jxta.document.StructuredDocumentFactory;
import net.jxta.document.TextElement;
import net.jxta.id.ID;
import net.jxta.id.IDFactory;
import net.jxta.membership.Authenticator;
import net.jxta.membership.MembershipService;
import net.jxta.peer.PeerID;
import net.jxta.peergroup.PeerGroup;
import net.jxta.protocol.ModuleImplAdvertisement;
import net.jxta.service.Service;

import net.jxta.exception.ProtocolNotSupportedException;
import net.jxta.exception.PeerGroupException;

/**
 *  A Membership Service implementation which is intended to be used with peer
 *  groups which require no real authentication.
 *
 * <p/>The none service allows you to claim any identity within the peergroup,
 * but for peergroups which use this Membership Service method, it is
 * likely that the identity is used only for informational purposes.
 *
 * <p/>A default credential with the name "nobody" is automatically available
 * without requiring authentication by this service.
 *
 */
public class NoneMembershipService implements MembershipService {
    
    /**
     *  Log4J Logger
     **/
    private static final Logger LOG = Logger.getLogger(NoneMembershipService.class.getName());
    
    /**
     *  Credential format for the None Membership service.
     *
     *  <p/>Credentials for the None Membership Service consist of the following
     *  unencrypted, unsigned XML tags:
     *
     *  <ul>
     *      <li>PeerGroupID</li>
     *      <li>PeerID</li>
     *      <li>Identity</li>
     *  </ul>
     **/
    private final static class NoneCredential implements Credential, CredentialPCLSupport {
        
        private NoneMembershipService source;
        
        private String whoami;
        
        private ID peerid;
        
        /**
         *  Whether the credential is valid.
         **/
        boolean valid = true;
        
        /**
         *  property change support
         **/
        private PropertyChangeSupport support = new PropertyChangeSupport( this );
        
        protected NoneCredential( NoneMembershipService source, String whoami ) {
            
            this.source = (NoneMembershipService) source;
            this.whoami = whoami;
            this.peerid = source.peergroup.getPeerID();
        }
        
        protected NoneCredential( NoneMembershipService source, Element root ) throws PeerGroupException {
            
            this.source = (NoneMembershipService) source;
            
            initialize( root );
        }
        
        /**
         * {@inheritDoc}
         **/
        public ID getPeerGroupID() {
            return source.peergroup.getPeerGroupID();
        }
        
        /**
         * {@inheritDoc}
         **/
        public ID getPeerID() {
            return peerid;
        }
        
        /**
         *
         **/
        private void setPeerID( PeerID peerid ) {
            this.peerid = peerid;
        }
        
        /**
         * {@inheritDoc}
         *
         * <p/>NoneCredential are always valid.
         **/
        public boolean isExpired() {
            return false;
        }
        
        /**
         * {@inheritDoc}
         *
         * <p/>NoneCredential are always valid.
         **/
        public boolean isValid() {
            return valid;
        }
        
        /**
         * {@inheritDoc}
         *
         * <p/>PasswdCredential are always valid except after resign.
         **/
        private void setValid( boolean valid ) {
            boolean oldValid = isValid();
            this.valid = valid;
            
            if( oldValid != valid ) {
                support.firePropertyChange( "valid", oldValid, valid );
            }
        }
        
        /**
         * {@inheritDoc}
         **/
        public Object getSubject() {
            return whoami;
        }
        
        /**
         *
         **/
        private void setSubject( String subject ) {
            whoami = (String) subject;
        }
        
        /**
         * {@inheritDoc}
         **/
        public Service getSourceService() {
            return source.getInterface();
        }
        
        /**
         * {@inheritDoc}
         **/
        public StructuredDocument getDocument(MimeMediaType as) throws Exception {
            StructuredDocument doc = StructuredDocumentFactory.newStructuredDocument( as, "jxta:Cred" );
            
            if( doc instanceof Attributable ) {
                ((Attributable)doc).addAttribute( "xmlns:jxta", "http://jxta.org" );
                ((Attributable)doc).addAttribute( "xml:space", "preserve" );
                ((Attributable)doc).addAttribute( "type", "jxta:NullCred" );
            }
            
            Element e = doc.createElement( "PeerGroupID", getPeerGroupID().toString() );
            doc.appendChild( e );
            
            e = doc.createElement( "PeerID", peerid.toString() );
            doc.appendChild( e );
            
            e = doc.createElement( "Identity", whoami );
            doc.appendChild( e );
            
            return doc;
        }
        
        /**
         *  Process an individual element from the document.
         *
         *  @param elem the element to be processed.
         *  @return true if the element was recognized, otherwise false.
         **/
        protected boolean handleElement( TextElement elem ) {
            if( elem.getName().equals("PeerGroupID")) {
                try {
                    URI gID = new URI( elem.getTextValue() );
                    ID pgid = IDFactory.fromURI( gID );
                    if( !pgid.equals( getPeerGroupID() ) ) {
                        throw new IllegalArgumentException( "Operation is from a different group. " + pgid + " != " + getPeerGroupID() );
                    }
                } catch ( URISyntaxException badID ) {
                    throw new IllegalArgumentException( "Bad PeerGroupID in advertisement: " + elem.getTextValue() );
                }
                return true;
            }
            
            if( elem.getName().equals("PeerID")) {
                try {
                    URI pID = new URI( elem.getTextValue() );
                    ID pid = IDFactory.fromURI( pID );
                    setPeerID( (PeerID) pid );
                } catch ( URISyntaxException badID ) {
                    throw new IllegalArgumentException( "Bad Peer ID in advertisement: " + elem.getTextValue() );
                } catch ( ClassCastException badID ) {
                    throw new IllegalArgumentException( "Id is not a peer id: " + elem.getTextValue() );
                }
                return true;
            }
            
            if( elem.getName().equals("Identity")) {
                setSubject( elem.getTextValue() );
                return true;
            }
            
            // element was not handled
            return false;
        }
        
        /**
         *  Intialize from a portion of a structured document.
         **/
        protected void initialize( Element root ) {
            
            if( !TextElement.class.isInstance( root ) ) {
                throw new IllegalArgumentException( getClass().getName() + " only supports TextElement" );
            }
            
            TextElement doc = (TextElement) root;
            
            String typedoctype = "";
            if( root instanceof Attributable ) {
                Attribute itsType = ((Attributable)root).getAttribute( "type" );
                if( null != itsType ) {
                    typedoctype = itsType.getValue();
                }
            }
            
            String doctype = doc.getName();
            
            if( !doctype.equals("jxta:NullCred") && !typedoctype.equals("jxta:NullCred") ) {
                throw new IllegalArgumentException( "Could not construct : "
                + getClass().getName() + "from doc containing a " + doctype );
            }
            
            Enumeration elements = doc.getChildren();
            
            while (elements.hasMoreElements()) {
                TextElement elem = (TextElement) elements.nextElement();
                
                if( !handleElement( elem ) ) {
                    if (LOG.isEnabledFor(Level.WARN)) {
                        LOG.warn("Unhandleded element '" + elem.getName() + "' in " + doc.getName() );
                    }
                };
            }
            
            // sanity check time!
            
            if( null == getSubject() ) {
                throw new IllegalArgumentException( "subject was never initialized." );
            }
            
            if( null == getPeerID() ) {
                throw new IllegalArgumentException( "peer id was never initialized." );
            }