Initial check-in

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/branches/rsm_branch@8733 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/commands/AdHocCommandHandler.java

@@ -112,21 +112,18 @@ public class AdHocCommandHandler extends IQHandler
         }
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
-        List<Element> answer = new ArrayList<Element>();
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
+        List<DiscoItem> answer = new ArrayList<DiscoItem>();
         if (!NAMESPACE.equals(node)) {
             answer = Collections.emptyList();
         }
         else {
-            Element item;
+        	
             for (AdHocCommand command : manager.getCommands()) {
                 // Only include commands that the sender can invoke (i.e. has enough permissions)
                 if (command.hasPermission(senderJID)) {
-                    item = DocumentHelper.createElement("item");
-                    item.addAttribute("jid", serverName);
-                    item.addAttribute("node", command.getCode());
-                    item.addAttribute("name", command.getLabel());
-
+					final DiscoItem item = new DiscoItem(new JID(serverName),
+							command.getLabel(), command.getCode(), null);
 					answer.add(item);
 				}
             }

src/java/org/jivesoftware/openfire/component/InternalComponentManager.java

@@ -445,8 +445,7 @@ public class InternalComponentManager extends BasicModule implements ComponentMa
                         return;
                     }
                     try {
-                        XMPPServer.getInstance().getIQDiscoItemsHandler().addComponentItem(packet.getFrom()
-                                .toBareJID(),
+                        XMPPServer.getInstance().getIQDiscoItemsHandler().addComponentItem(packet.getFrom(),
                                 identity.attributeValue("name"));
                         if (component instanceof ComponentSession.ExternalComponent) {
                             ComponentSession.ExternalComponent externalComponent =

src/java/org/jivesoftware/openfire/disco/DiscoItem.java

@@ -11,51 +11,169 @@
 
 package org.jivesoftware.openfire.disco;
 
+import org.dom4j.DocumentHelper;
+import org.dom4j.Element;
+import org.jivesoftware.util.rsm.Result;
+import org.xmpp.packet.JID;
+
 /**
- * An item is associated with an XMPP Entity, usually thought of a children of the parent
- * entity and normally are addressable as a JID.<p>
- * <p/>
- * An item associated with an entity may not be addressable as a JID. In order to handle
- * such items, Service Discovery uses an optional 'node' attribute that supplements the
- * 'jid' attribute.
+ * <p>
+ * An item is associated with an XMPP Entity, usually thought of a children of
+ * the parent entity and normally are addressable as a JID.
+ * </p>
+ * <p>
+ * An item associated with an entity may not be addressable as a JID. In order
+ * to handle such items, Service Discovery uses an optional 'node' attribute
+ * that supplements the 'jid' attribute.
+ * </p>
  * 
  * @author Gaston Dombiak
  */
-public interface DiscoItem {
+public class DiscoItem implements Result {
+
+	private final JID jid;
+
+	private final String name;
+
+	private final String node;
+
+	private final String action;
+
+	/**
+	 * <p>
+	 * Creates a new DiscoItem instance.
+	 * </p>
+	 * 
+	 * @param jid
+	 *            specifies the Jabber ID of the item "owner" or location
+	 *            (required).
+	 * @param name
+	 *            specifies a natural-language name for the item (can be null).
+	 * @param node
+	 *            specifies the particular node associated with the JID of the
+	 *            item "owner" or location (can be null).
+	 * @param action
+	 *            specifies the action to be taken for the item.
+	 * @throws IllegalArgumentException
+	 *             If a required parameter was null, or if the supplied 'action'
+	 *             parameter has another value than 'null', "update" or
+	 *             "remove".
+	 */
+	public DiscoItem(JID jid, String name, String node, String action) {
+		if (jid == null) {
+			throw new IllegalArgumentException("Argument 'jid' cannot be null.");
+		}
+
+		if (action != null && !action.equals("update")
+				&& !action.equals("remove")) {
+			throw new IllegalArgumentException(
+					"Argument 'jid' cannot have any other value than null, \"update\" or \"remove\".");
+		}
+
+		this.jid = jid;
+		this.name = name;
+		this.node = node;
+		this.action = action;
+	}
 
 	/**
+	 * <p>
 	 * Returns the entity's ID.
+	 * </p>
 	 * 
 	 * @return the entity's ID.
 	 */
-    public abstract String getJID();
+	public JID getJID() {
+		return jid;
+	}
 
 	/**
-     * Returns the node attribute that supplements the 'jid' attribute. A node is merely
-     * something that is associated with a JID and for which the JID can provide information.<p>
-     * <p/>
-     * Node attributes SHOULD be used only when trying to provide or query information which
-     * is not directly addressable.
+	 * <p>
+	 * Returns the node attribute that supplements the 'jid' attribute. A node
+	 * is merely something that is associated with a JID and for which the JID
+	 * can provide information.
+	 * </p>
+	 * <p>
+	 * Node attributes SHOULD be used only when trying to provide or query
+	 * information which is not directly addressable.
+	 * </p>
 	 * 
 	 * @return the node attribute that supplements the 'jid' attribute
 	 */
-    public abstract String getNode();
+	public String getNode() {
+		return node;
+	}
 
 	/**
-     * Returns the entity's name. The entity's name specifies in natural-language the name for the
-     * item.
+	 * <p>
+	 * Returns the entity's name. The entity's name specifies in
+	 * natural-language the name for the item.
+	 * </p>
 	 * 
 	 * @return the entity's name.
 	 */
-    public abstract String getName();
+	public String getName() {
+		return name;
+	}
 
 	/**
-     * Returns the action (i.e. update or remove) that indicates what must be done with this item or
-     * null if none. An "update" action requests the server to create or update the item. Whilst a
-     * "remove" action requests to remove the item.
+	 * <p>
+	 * Returns the action (i.e. update or remove) that indicates what must be
+	 * done with this item or null if none. An "update" action requests the
+	 * server to create or update the item. Whilst a "remove" action requests to
+	 * remove the item.
+	 * </p>
 	 * 
-     * @return the action (i.e. update or remove) that indicates what must be done with this item or
-     *         null if none.
+	 * @return the action (i.e. update or remove) that indicates what must be
+	 *         done with this item or null if none.
 	 */
-    public abstract String getAction();
+	public String getAction() {
+		return action;
+	}
+
+	/**
+	 * Returns a dom4j element that represents this DiscoItem object.
+	 * 
+	 * @return element representing this object.
+	 */
+	public Element getElement() {
+		final Element element = DocumentHelper.createElement("item");
+		if (action != null) {
+			element.addAttribute("action", action);
+		}
+
+		if (jid != null) {
+			element.addAttribute("jid", jid.toString());
+		}
+
+		if (name != null) {
+			element.addAttribute("name", name);
+		}
+
+		if (node != null) {
+			element.addAttribute("node", node);
+		}
+
+		return element;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.jivesoftware.util.resultsetmanager.Result#getUID()
+	 */
+	public String getUID() {
+		final StringBuilder sb = new StringBuilder(jid.toString());
+		if (name != null) {
+			sb.append(name);
+		}
+		if (node != null) {
+			sb.append(node);
+		}
+		if (action != null) {
+			sb.append(action);
+		}
+
+		return sb.toString();
+	}
 }

src/java/org/jivesoftware/openfire/disco/DiscoItemsProvider.java

@@ -11,11 +11,10 @@
 
 package org.jivesoftware.openfire.disco;
 
-import org.dom4j.Element;
-import org.xmpp.packet.JID;
-
 import java.util.Iterator;
 
+import org.xmpp.packet.JID;
+
 /**
  * A DiscoItemsProvider is responsible for providing the items associated with a JID's name and
  * node. For example, the room service could implement this interface in order to provide
@@ -30,7 +29,7 @@ import java.util.Iterator;
 public interface DiscoItemsProvider {
 
     /**
-     * Returns an Iterator (of Element) with the target entity's items or null if none. Each Element
+     * Returns an Iterator (of DiscoItem) with the target entity's items or null if none. Each DiscoItem
      * must include a JID attribute and may include the name and node attributes of the entity. In
      * case that the sender of the disco request is not authorized to discover items an
      * UnauthorizedException will be thrown.
@@ -38,8 +37,8 @@ public interface DiscoItemsProvider {
      * @param name the recipient JID's name.
      * @param node the requested disco node.
      * @param senderJID the XMPPAddress of user that sent the disco items request.
-     * @return an Iterator (of Element) with the target entity's items or null if none.
+     * @return an Iterator (of DiscoItem) with the target entity's items or null if none.
      */
-    public abstract Iterator<Element> getItems(String name, String node, JID senderJID);
+    public abstract Iterator<DiscoItem> getItems(String name, String node, JID senderJID);
 
 }

src/java/org/jivesoftware/openfire/disco/DiscoServerItem.java

@@ -11,6 +11,8 @@
 
 package org.jivesoftware.openfire.disco;
 
+import org.xmpp.packet.JID;
+
 /**
  * Represent a DiscoItem provided by the server. Therefore, the DiscoServerItems are responsible
  * for providing the DiscoInfoProvider and DiscoItemsProvider that will provide the information and
@@ -26,8 +28,29 @@ package org.jivesoftware.openfire.disco;
  *
  * @author Gaston Dombiak
  */
-public interface DiscoServerItem extends DiscoItem {
+public class DiscoServerItem extends DiscoItem {
+
+	private final DiscoInfoProvider infoProvider;
+	private final DiscoItemsProvider itemsProvider;
+	
+	public DiscoServerItem(JID jid, String name, String node, String action,
+                           DiscoInfoProvider infoProvider, DiscoItemsProvider itemsProvider)
+    {
+		super(jid, name, node, action);
+		
+		if (infoProvider == null)
+		{
+			throw new IllegalArgumentException("Argument 'infoProvider' cannot be null.");
+		}
+		
+		if (itemsProvider == null)
+		{
+			throw new IllegalArgumentException("Argument 'itemsProvider' cannot be null.");
+		}
 		
+		this.infoProvider = infoProvider;
+		this.itemsProvider = itemsProvider;
+	}
     /**
      * Returns the DiscoInfoProvider responsible for providing the information related to this item.
      * The DiscoInfoProvider will be automatically included in IQDiscoInfoHandler as the provider
@@ -35,7 +58,9 @@ public interface DiscoServerItem extends DiscoItem {
      *
      * @return the DiscoInfoProvider responsible for providing the information related to this item.
      */
-    public abstract DiscoInfoProvider getDiscoInfoProvider();
+    public DiscoInfoProvider getDiscoInfoProvider() {
+    	return infoProvider;
+    }
 
     /**
      * Returns the DiscoItemsProvider responsible for providing the items related to this item.
@@ -44,5 +69,7 @@ public interface DiscoServerItem extends DiscoItem {
      *
      * @return the DiscoItemsProvider responsible for providing the items related to this item.
      */
-    public abstract DiscoItemsProvider getDiscoItemsProvider();
+    public DiscoItemsProvider getDiscoItemsProvider() {
+    	return itemsProvider;
+    }
 }

src/java/org/jivesoftware/openfire/disco/IQDiscoInfoHandler.java

@@ -25,6 +25,8 @@ import org.jivesoftware.openfire.handler.IQHandler;
 import org.jivesoftware.openfire.user.UserManager;
 import org.jivesoftware.openfire.user.UserNotFoundException;
 import org.jivesoftware.util.JiveGlobals;
+import org.jivesoftware.util.Log;
+import org.jivesoftware.util.rsm.ResultSet;
 import org.jivesoftware.util.cache.Cache;
 import org.jivesoftware.util.cache.CacheFactory;
 import org.jivesoftware.util.lock.LockManager;
@@ -59,6 +61,7 @@ import java.util.concurrent.locks.Lock;
  */
 public class IQDiscoInfoHandler extends IQHandler implements ClusterEventListener {
 
+    private static final String NAMESPACE_DISCO_INFO = "http://jabber.org/protocol/disco#info";
     private Map<String, DiscoInfoProvider> entities = new HashMap<String, DiscoInfoProvider>();
     private Set<String> localServerFeatures = new CopyOnWriteArraySet<String>();
     private Cache<String, Set<NodeID>> serverFeatures;
@@ -71,7 +74,8 @@ public class IQDiscoInfoHandler extends IQHandler implements ClusterEventListene
 
     public IQDiscoInfoHandler() {
         super("XMPP Disco Info Handler");
-        info = new IQHandlerInfo("query", "http://jabber.org/protocol/disco#info");
+        info = new IQHandlerInfo("query", NAMESPACE_DISCO_INFO);
+        addServerFeature(NAMESPACE_DISCO_INFO);
         // Initialize the user identity and features collections (optimization to avoid creating
         // the same objects for each response)
         Element userIdentity = DocumentHelper.createElement("identity");
@@ -82,7 +86,7 @@ public class IQDiscoInfoHandler extends IQHandler implements ClusterEventListene
         userIdentity.addAttribute("category", "account");
         userIdentity.addAttribute("type", "registered");
         registeredUserIdentities.add(userIdentity);
-        userFeatures.add("http://jabber.org/protocol/disco#info");
+        userFeatures.add(NAMESPACE_DISCO_INFO);
     }
 
     public IQHandlerInfo getInfo() {
@@ -99,8 +103,10 @@ public class IQDiscoInfoHandler extends IQHandler implements ClusterEventListene
         // We consider the host of the recipient JID of the packet as the entity. It's the
         // DiscoInfoProvider responsibility to provide information about the JID's name together
         // with any possible requested node.
-        DiscoInfoProvider infoProvider = getProvider(packet.getTo() == null ?
-                XMPPServer.getInstance().getServerInfo().getName() : packet.getTo().getDomain());
+        final String toAddress = packet.getTo() == null ? XMPPServer
+				.getInstance().getServerInfo().getName() : packet.getTo()
+				.getDomain();
+		DiscoInfoProvider infoProvider = getProvider(toAddress);
         if (infoProvider != null) {
             // Get the JID's name
             String name = packet.getTo() == null ? null : packet.getTo().getNode();
@@ -119,17 +125,49 @@ public class IQDiscoInfoHandler extends IQHandler implements ClusterEventListene
 
                 // Add to the reply all the identities provided by the DiscoInfoProvider
                 Element identity;
-                Iterator identities = infoProvider.getIdentities(name, node, packet.getFrom());
+                Iterator<Element> identities = infoProvider.getIdentities(name, node,
+                        packet.getFrom());
                 while (identities.hasNext()) {
-                    identity = (Element)identities.next();
+                    identity = identities.next();
                     identity.setQName(new QName(identity.getName(), queryElement.getNamespace()));
                     queryElement.add((Element)identity.clone());
                 }
 
                 // Add to the reply all the features provided by the DiscoInfoProvider
-                Iterator features = infoProvider.getFeatures(name, node, packet.getFrom());
+                Iterator<String> features = infoProvider.getFeatures(name, node, packet.getFrom());
+                boolean hasDiscoInfoFeature = false;
+                boolean hasDiscoItemsFeature = false;
+                boolean hasResultSetManagementFeature = false;
+
                 while (features.hasNext()) {
-                    queryElement.addElement("feature").addAttribute("var", (String)features.next());
+					final String feature = features.next();
+					queryElement.addElement("feature").addAttribute("var", feature);
+					if (feature.equals(NAMESPACE_DISCO_INFO)) {
+						hasDiscoInfoFeature = true;
+					} else if (feature.equals("http://jabber.org/protocol/disco#items")) {
+						hasDiscoItemsFeature = true;
+					} else if (feature.equals(ResultSet.NAMESPACE_RESULT_SET_MANAGEMENT)) {
+						hasResultSetManagementFeature = true;
+					}
+
+				}
+
+				if (hasDiscoItemsFeature && !hasResultSetManagementFeature) {
+					// IQDiscoItemsHandler provides result set management
+					// support.
+					queryElement.addElement("feature").addAttribute("var",
+							ResultSet.NAMESPACE_RESULT_SET_MANAGEMENT);
+				}
+
+                if (!hasDiscoInfoFeature) {
+					// XEP-0030 requires that every entity that supports service
+					// discovery broadcasts the disco#info feature.
+					Log.info("InfoProvider for '" + toAddress
+									+ "' does not return the disco#info feature. "
+									+ "Openfire will add the feature on the entities behalf, "
+									+ "but the entities response to Service Discovery request should be modified.");
+					queryElement.addElement("feature").addAttribute("var",
+							NAMESPACE_DISCO_INFO);
 				}
 
                 // Add to the reply the extended info (XDataForm) provided by the DiscoInfoProvider

src/java/org/jivesoftware/openfire/disco/IQDiscoItemsHandler.java

@@ -31,9 +31,12 @@ import org.jivesoftware.util.cache.Cache;
 import org.jivesoftware.util.cache.CacheFactory;
 import org.jivesoftware.util.cache.ExternalizableUtil;
 import org.jivesoftware.util.lock.LockManager;
+import org.jivesoftware.util.rsm.ResultSet;
+import org.jivesoftware.util.rsm.ResultSetImpl;
 import org.xmpp.packet.IQ;
 import org.xmpp.packet.JID;
 import org.xmpp.packet.PacketError;
+import org.xmpp.packet.PacketError.Condition;
 
 import java.io.Externalizable;
 import java.io.IOException;
@@ -67,16 +70,18 @@ import java.util.concurrent.locks.Lock;
  */
 public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProvider, ClusterEventListener {
 
+    public static final String NAMESPACE_DISCO_ITEMS = "http://jabber.org/protocol/disco#items";
     private Map<String,DiscoItemsProvider> entities = new HashMap<String,DiscoItemsProvider>();
     private Map<String, Element> localServerItems = new HashMap<String, Element>();
     private Cache<String, ClusteredServerItem> serverItems;
-    private Map<String, DiscoItemsProvider> serverNodeProviders = new ConcurrentHashMap<String, DiscoItemsProvider>();
+    private Map<String, DiscoItemsProvider> serverNodeProviders
+            = new ConcurrentHashMap<String, DiscoItemsProvider>();
     private IQHandlerInfo info;
     private IQDiscoInfoHandler infoHandler;
 
     public IQDiscoItemsHandler() {
         super("XMPP Disco Items Handler");
-        info = new IQHandlerInfo("query", "http://jabber.org/protocol/disco#items");
+        info = new IQHandlerInfo("query", NAMESPACE_DISCO_ITEMS);
     }
 
     public IQHandlerInfo getInfo() {
@@ -113,19 +118,72 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
             String node = iq.attributeValue("node");
 
             // Check if we have items associated with the requested name and node
-            Iterator<Element> itemsItr = itemsProvider.getItems(name, node, packet.getFrom());
+            Iterator<DiscoItem> itemsItr = itemsProvider.getItems(name, node,
+					packet.getFrom());
 			if (itemsItr != null) {
 				reply.setChildElement(iq.createCopy());
 				Element queryElement = reply.getChildElement();
 
-                // Add to the reply all the items provided by the DiscoItemsProvider
+				// See if the requesting entity would like to apply 'result set
+				// management'
+				final Element rsmElement = packet.getChildElement().element(
+						QName.get("set",
+								ResultSet.NAMESPACE_RESULT_SET_MANAGEMENT));
+
+				// apply RSM only if the element exists, and the (total) results
+				// set is not empty.
+				final boolean applyRSM = rsmElement != null
+						&& itemsItr.hasNext();
+
+				if (applyRSM) {
+					if (!ResultSet.isValidRSMRequest(rsmElement))
+					{
+						reply.setError(Condition.bad_request);
+						return reply;
+					}
+
+					// Calculate which results to include.
+					final List<DiscoItem> rsmResults;
+					final List<DiscoItem> allItems = new ArrayList<DiscoItem>();
+					while (itemsItr.hasNext()) {
+						allItems.add(itemsItr.next());
+					}
+					final ResultSet<DiscoItem> rs = new ResultSetImpl<DiscoItem>(
+							allItems);
+					try {
+						rsmResults = rs.applyRSMDirectives(rsmElement);
+					} catch (NullPointerException e) {
+						final IQ itemNotFound = IQ.createResultIQ(packet);
+						itemNotFound.setError(Condition.item_not_found);
+						return itemNotFound;
+					}
+
+					// add the applicable results to the IQ-result
+					for (DiscoItem item : rsmResults) {
+						final Element resultElement = item.getElement();
+						resultElement.setQName(new QName(resultElement
+								.getName(), queryElement.getNamespace()));
+						queryElement.add(resultElement.createCopy());
+					}
+
+					// overwrite the 'set' element.
+					queryElement.remove(queryElement.element(
+							QName.get("set",
+									ResultSet.NAMESPACE_RESULT_SET_MANAGEMENT)));
+					queryElement.add(rs.generateSetElementFromResults(rsmResults));
+				} else {
+					// don't apply RSM:
+					// Add to the reply all the items provided by the
+					// DiscoItemsProvider
 					Element item;
 					while (itemsItr.hasNext()) {
-                    item = itemsItr.next();
-                    item.setQName(new QName(item.getName(), queryElement.getNamespace()));
+						item = itemsItr.next().getElement();
+						item.setQName(new QName(item.getName(), queryElement
+								.getNamespace()));
 						queryElement.add(item.createCopy());
 					}
 				}
+			}
             else {
                 // If the DiscoItemsProvider has no items for the requested name and node
                 // then answer a not found error
@@ -193,10 +251,10 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
         while (items.hasNext()) {
             discoItem = items.next();
             // Add the element to the list of items related to the server
-            addComponentItem(discoItem.getJID(), discoItem.getNode(), discoItem.getName());
+            addComponentItem(discoItem.getJID().toString(), discoItem.getNode(), discoItem.getName());
 
             // Add the new item as a valid entity that could receive info and items disco requests
-            String host = new JID(discoItem.getJID()).getDomain();
+            String host = discoItem.getJID().getDomain();
             infoHandler.setProvider(host, discoItem.getDiscoInfoProvider());
             setProvider(host, discoItem.getDiscoItemsProvider());
         }
@@ -217,10 +275,10 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
         while (items.hasNext()) {
             discoItem = items.next();
             // Remove the item from the server items list
-            removeComponentItem(discoItem.getJID());
+            removeComponentItem(discoItem.getJID().toString());
 
             // Remove the item as a valid entity that could receive info and items disco requests
-            String host = new JID(discoItem.getJID()).getDomain();
+            String host = discoItem.getJID().getDomain();
             infoHandler.removeProvider(host);
             removeProvider(host);
         }
@@ -343,7 +401,7 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
 
     public Iterator<String> getFeatures() {
         List<String> features = new ArrayList<String>();
-        features.add("http://jabber.org/protocol/disco#items");
+        features.add(NAMESPACE_DISCO_ITEMS);
         // TODO Comment out this line when publishing of client items is implemented
         //features.add("http://jabber.org/protocol/disco#publish");
         return features.iterator();
@@ -418,7 +476,7 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
 
     private DiscoItemsProvider getServerItemsProvider() {
         return new DiscoItemsProvider() {
-            public Iterator<Element> getItems(String name, String node, JID senderJID) {
+            public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
                 if (node != null) {
                     // Check if there is a provider for the requested node
                     if (serverNodeProviders.get(node) != null) {
@@ -433,8 +491,7 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
                     }
                     return answer.iterator();
                 }
-                else {
-                    List<Element> answer = new ArrayList<Element>();
+                final List<DiscoItem> answer = new ArrayList<DiscoItem>();
                 try {
                     User user = UserManager.getInstance().getUser(name);
                     RosterItem item = user.getRoster().getRosterItem(senderJID);
@@ -443,9 +500,7 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
                     if (item.getSubStatus() == RosterItem.SUB_FROM ||
                             item.getSubStatus() == RosterItem.SUB_BOTH) {
                         for (Session session : SessionManager.getInstance().getSessions(name)) {
-                                Element element = DocumentHelper.createElement("item");
-                                element.addAttribute("jid", session.getAddress().toString());
-                                answer.add(element);
+                            answer.add(new DiscoItem(session.getAddress(), null, null, null));
                         }
                     }
                     return answer.iterator();
@@ -454,7 +509,6 @@ public class IQDiscoItemsHandler extends IQHandler implements ServerFeaturesProv
                     return answer.iterator();
                 }
             }
-            }
         };
     }
 

src/java/org/jivesoftware/openfire/filetransfer/proxy/FileTransferProxy.java

@@ -11,12 +11,26 @@
 
 package org.jivesoftware.openfire.filetransfer.proxy;
 
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
 import org.dom4j.DocumentHelper;
 import org.dom4j.Element;
-import org.jivesoftware.openfire.*;
+import org.jivesoftware.openfire.IQHandlerInfo;
+import org.jivesoftware.openfire.PacketException;
+import org.jivesoftware.openfire.PacketRouter;
+import org.jivesoftware.openfire.RoutableChannelHandler;
+import org.jivesoftware.openfire.RoutingTable;
+import org.jivesoftware.openfire.XMPPServer;
 import org.jivesoftware.openfire.auth.UnauthorizedException;
 import org.jivesoftware.openfire.container.BasicModule;
 import org.jivesoftware.openfire.disco.DiscoInfoProvider;
+import org.jivesoftware.openfire.disco.DiscoItem;
 import org.jivesoftware.openfire.disco.DiscoItemsProvider;
 import org.jivesoftware.openfire.disco.DiscoServerItem;
 import org.jivesoftware.openfire.disco.ServerItemsProvider;
@@ -31,10 +45,6 @@ import org.xmpp.packet.JID;
 import org.xmpp.packet.Packet;
 import org.xmpp.packet.PacketError;
 
-import java.net.InetAddress;
-import java.net.UnknownHostException;
-import java.util.*;
-
 /**
  * Manages the transfering of files between two remote entities on the jabber network.
  * This class acts independtly as a Jabber component from the rest of the server, according to
@@ -284,31 +294,8 @@ public class FileTransferProxy extends BasicModule
             return items.iterator();
         }
 
-        items.add(new DiscoServerItem() {
-            public String getJID() {
-                return getServiceDomain();
-            }
-
-            public String getName() {
-                return "Socks 5 Bytestreams Proxy";
-            }
-
-            public String getAction() {
-                return null;
-            }
-
-            public String getNode() {
-                return null;
-            }
-
-            public DiscoInfoProvider getDiscoInfoProvider() {
-                return FileTransferProxy.this;
-            }
-
-            public DiscoItemsProvider getDiscoItemsProvider() {
-                return FileTransferProxy.this;
-            }
-        });
+        items.add(new DiscoServerItem(new JID(getServiceDomain()),
+                "Socks 5 Bytestreams Proxy", null, null, this, this));
         return items.iterator();
     }
 
@@ -338,9 +325,9 @@ public class FileTransferProxy extends BasicModule
         return true;
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
         // A proxy server has no items
-        return new ArrayList<Element>().iterator();
+        return new ArrayList<DiscoItem>().iterator();
     }
 
     public void process(Packet packet) throws UnauthorizedException, PacketException {

src/java/org/jivesoftware/openfire/handler/IQOfflineMessagesHandler.java

@@ -159,19 +159,15 @@ public class IQOfflineMessagesHandler extends IQHandler implements ServerFeature
         return NAMESPACE.equals(node) && userManager.isRegisteredUser(senderJID.getNode());
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
         // Mark that offline messages shouldn't be sent when the user becomes available
         stopOfflineFlooding(senderJID);
-        List<Element> answer = new ArrayList<Element>();
-        Element item;
+        List<DiscoItem> answer = new ArrayList<DiscoItem>();
         for (OfflineMessage offlineMessage : messageStore.getMessages(senderJID.getNode(), false)) {
-            item = DocumentHelper.createElement("item");
-            item.addAttribute("jid", senderJID.toBareJID());
-            item.addAttribute("name", offlineMessage.getFrom().toString());
+        	final DiscoItem item;
             synchronized (dateFormat) {
-                item.addAttribute("node", dateFormat.format(offlineMessage.getCreationDate()));
+            	 item = new DiscoItem(senderJID, offlineMessage.getFrom().toString(), dateFormat.format(offlineMessage.getCreationDate()), null);
             }
-
             answer.add(item);
         }
 

src/java/org/jivesoftware/openfire/mediaproxy/MediaProxyService.java

@@ -17,6 +17,7 @@ import org.jivesoftware.openfire.*;
 import org.jivesoftware.openfire.auth.UnauthorizedException;
 import org.jivesoftware.openfire.container.BasicModule;
 import org.jivesoftware.openfire.disco.DiscoInfoProvider;
+import org.jivesoftware.openfire.disco.DiscoItem;
 import org.jivesoftware.openfire.disco.DiscoItemsProvider;
 import org.jivesoftware.openfire.disco.DiscoServerItem;
 import org.jivesoftware.openfire.disco.ServerItemsProvider;
@@ -98,14 +99,14 @@ public class MediaProxyService extends BasicModule
             XMPPServer.getInstance().getIQDiscoItemsHandler().addServerItemsProvider(this);
         } else {
             if (echo != null) echo.cancel();
-            XMPPServer.getInstance().getIQDiscoItemsHandler().removeComponentItem(getAddress().toString());
+            XMPPServer.getInstance().getIQDiscoItemsHandler().removeComponentItem(getAddress());
         }
     }
 
     public void stop() {
         super.stop();
         mediaProxy.stopProxy();
-        XMPPServer.getInstance().getIQDiscoItemsHandler().removeComponentItem(getAddress().toString());
+        XMPPServer.getInstance().getIQDiscoItemsHandler().removeComponentItem(getAddress());
         routingTable.removeComponentRoute(getAddress());
         if (echo != null) echo.cancel();
     }
@@ -117,9 +118,9 @@ public class MediaProxyService extends BasicModule
         return serviceName;
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
         // A proxy server has no items
-        return new ArrayList<Element>().iterator();
+        return new ArrayList<DiscoItem>().iterator();
     }
 
     public void process(Packet packet) throws UnauthorizedException, PacketException {
@@ -293,31 +294,8 @@ public class MediaProxyService extends BasicModule
             return items.iterator();
         }
 
-        items.add(new DiscoServerItem() {
-            public String getJID() {
-                return getServiceDomain();
-            }
-
-            public String getName() {
-                return "Media Proxy Service";
-            }
-
-            public String getAction() {
-                return null;
-            }
-
-            public String getNode() {
-                return null;
-            }
-
-            public DiscoInfoProvider getDiscoInfoProvider() {
-                return MediaProxyService.this;
-            }
-
-            public DiscoItemsProvider getDiscoItemsProvider() {
-                return MediaProxyService.this;
-            }
-        });
+        final DiscoServerItem item = new DiscoServerItem(new JID(getServiceDomain()), "Media Proxy Service", null, null, this, this);                
+        items.add(item);
         return items.iterator();
     }
 

src/java/org/jivesoftware/openfire/muc/spi/MultiUserChatServerImpl.java

@@ -19,6 +19,7 @@ import org.jivesoftware.openfire.cluster.ClusterEventListener;
 import org.jivesoftware.openfire.cluster.ClusterManager;
 import org.jivesoftware.openfire.container.BasicModule;
 import org.jivesoftware.openfire.disco.DiscoInfoProvider;
+import org.jivesoftware.openfire.disco.DiscoItem;
 import org.jivesoftware.openfire.disco.DiscoItemsProvider;
 import org.jivesoftware.openfire.disco.DiscoServerItem;
 import org.jivesoftware.openfire.disco.ServerItemsProvider;
@@ -960,37 +961,19 @@ public class MultiUserChatServerImpl extends BasicModule implements MultiUserCha
             return null;
         }
         ArrayList<DiscoServerItem> items = new ArrayList<DiscoServerItem>();
-        items.add(new DiscoServerItem() {
-            public String getJID() {
-                return getServiceDomain();
-            }
-
-            public String getName() {
+        final String name;
         // Check if there is a system property that overrides the default value
         String serviceName = JiveGlobals.getProperty("muc.service-name");
         if (serviceName != null && serviceName.trim().length() > 0) {
-                    return serviceName;
+            name = serviceName;
         }
+        else {
         	// Return the default service name based on the current locale
-                return LocaleUtils.getLocalizedString("muc.service-name");
+        	name = LocaleUtils.getLocalizedString("muc.service-name");
         }
 
-            public String getAction() {
-                return null;
-            }
-
-            public String getNode() {
-                return null;
-            }
-
-            public DiscoInfoProvider getDiscoInfoProvider() {
-                return MultiUserChatServerImpl.this;
-            }
-
-            public DiscoItemsProvider getDiscoItemsProvider() {
-                return MultiUserChatServerImpl.this;
-            }
-        });
+        final DiscoServerItem item = new DiscoServerItem(new JID(getServiceDomain()), name, null, null, this, this);
+        items.add(item);
         return items.iterator();
     }
 
@@ -1150,22 +1133,17 @@ public class MultiUserChatServerImpl extends BasicModule implements MultiUserCha
         return false;
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
         // Check if the service is disabled. Info is not available when disabled.
         if (!isServiceEnabled()) {
             return null;
         }
-        List<Element> answer = new ArrayList<Element>();
+        List<DiscoItem> answer = new ArrayList<DiscoItem>();
         if (name == null && node == null) {
-            Element item;
             // Answer all the public rooms as items
             for (MUCRoom room : rooms.values()) {
                 if (canDiscoverRoom(room)) {
-                    item = DocumentHelper.createElement("item");
-                    item.addAttribute("jid", room.getRole().getRoleAddress().toString());
-                    item.addAttribute("name", room.getNaturalLanguageName());
-
-                    answer.add(item);
+                    answer.add(new DiscoItem(room.getRole().getRoleAddress(), room.getNaturalLanguageName(), null, null));
                 }
             }
         }
@@ -1173,13 +1151,9 @@ public class MultiUserChatServerImpl extends BasicModule implements MultiUserCha
             // Answer the room occupants as items if that info is publicly available
             MUCRoom room = getChatRoom(name);
             if (room != null && canDiscoverRoom(room)) {
-                Element item;
                 for (MUCRole role : room.getOccupants()) {
                     // TODO Should we filter occupants that are invisible (presence is not broadcasted)?
-                    item = DocumentHelper.createElement("item");
-                    item.addAttribute("jid", role.getRoleAddress().toString());
-
-                    answer.add(item);
+                    answer.add(new DiscoItem(role.getRoleAddress(), null, null, null));
                 }
             }
         }

src/java/org/jivesoftware/openfire/pubsub/PubSubModule.java

@@ -22,6 +22,7 @@ import org.jivesoftware.openfire.cluster.ClusterManager;
 import org.jivesoftware.openfire.component.InternalComponentManager;
 import org.jivesoftware.openfire.container.BasicModule;
 import org.jivesoftware.openfire.disco.DiscoInfoProvider;
+import org.jivesoftware.openfire.disco.DiscoItem;
 import org.jivesoftware.openfire.disco.DiscoItemsProvider;
 import org.jivesoftware.openfire.disco.DiscoServerItem;
 import org.jivesoftware.openfire.disco.ServerItemsProvider;
@@ -468,32 +469,8 @@ public class PubSubModule extends BasicModule implements ServerItemsProvider, Di
 
     public Iterator<DiscoServerItem> getItems() {
         ArrayList<DiscoServerItem> items = new ArrayList<DiscoServerItem>();
-
-        items.add(new DiscoServerItem() {
-            public String getJID() {
-                return getServiceDomain();
-            }
-
-            public String getName() {
-                return "Publish-Subscribe service";
-            }
-
-            public String getAction() {
-                return null;
-            }
-
-            public String getNode() {
-                return null;
-            }
-
-            public DiscoInfoProvider getDiscoInfoProvider() {
-                return PubSubModule.this;
-            }
-
-            public DiscoItemsProvider getDiscoItemsProvider() {
-                return PubSubModule.this;
-            }
-        });
+        final DiscoServerItem item = new DiscoServerItem(new JID(getServiceDomain()), "Publish-Subscribe service", null, null, this, this);
+        items.add(item);
         return items.iterator();
     }
 
@@ -636,18 +613,14 @@ public class PubSubModule extends BasicModule implements ServerItemsProvider, Di
         return false;
     }
 
-    public Iterator<Element> getItems(String name, String node, JID senderJID) {
-        List<Element> answer = new ArrayList<Element>();
+    public Iterator<DiscoItem> getItems(String name, String node, JID senderJID) {
+        List<DiscoItem> answer = new ArrayList<DiscoItem>();
         String serviceDomain = getServiceDomain();
         if (name == null && node == null) {
-            Element item;
             // Answer all first level nodes
             for (Node pubNode : rootCollectionNode.getNodes()) {
                 if (canDiscoverNode(pubNode)) {
-                    item = DocumentHelper.createElement("item");
-                    item.addAttribute("jid", serviceDomain);
-                    item.addAttribute("node", pubNode.getNodeID());
-                    item.addAttribute("name", pubNode.getName());
+                	final DiscoItem item = new DiscoItem(new JID(serviceDomain), pubNode.getName(), pubNode.getNodeID(), null);
                     answer.add(item);
                 }
             }
@@ -656,25 +629,18 @@ public class PubSubModule extends BasicModule implements ServerItemsProvider, Di
             Node pubNode = getNode(node);
             if (pubNode != null && canDiscoverNode(pubNode)) {
                 if (pubNode.isCollectionNode()) {
-                    Element item;
                     // Answer all nested nodes as items
                     for (Node nestedNode : pubNode.getNodes()) {
                         if (canDiscoverNode(nestedNode)) {
-                            item = DocumentHelper.createElement("item");
-                            item.addAttribute("jid", serviceDomain);
-                            item.addAttribute("node", nestedNode.getNodeID());
-                            item.addAttribute("name", nestedNode.getName());
+                        	final DiscoItem item = new DiscoItem(new JID(serviceDomain), nestedNode.getName(), nestedNode.getNodeID(), null);
                             answer.add(item);
                         }
                     }
                 }
                 else {
                     // This is a leaf node so answer the published items which exist on the service
-                    Element item;
                     for (PublishedItem publishedItem : pubNode.getPublishedItems()) {
-                        item = DocumentHelper.createElement("item");
-                        item.addAttribute("jid", serviceDomain);
-                        item.addAttribute("name", publishedItem.getID());
+                    	final DiscoItem item = new DiscoItem(new JID(serviceDomain), publishedItem.getID(), null, null);
                         answer.add(item);
                     }
                 }

src/java/org/jivesoftware/openfire/user/User.java

@@ -20,6 +20,7 @@ import org.jivesoftware.util.Log;
 import org.jivesoftware.util.cache.CacheSizes;
 import org.jivesoftware.util.cache.Cacheable;
 import org.jivesoftware.util.cache.ExternalizableUtil;
+import org.jivesoftware.util.rsm.Result;
 
 import java.io.Externalizable;
 import java.io.IOException;
@@ -42,7 +43,7 @@ import java.util.concurrent.ConcurrentHashMap;
  *
  * @author Matt Tucker
  */
-public class User implements Cacheable, Externalizable {
+public class User implements Cacheable, Externalizable, Result {
 
     private static final String LOAD_PROPERTIES =
         "SELECT name, propValue FROM jiveUserProp WHERE username=?";
@@ -529,4 +530,8 @@ public class User implements Cacheable, Externalizable {
         creationDate = new Date(ExternalizableUtil.getInstance().readLong(in));
         modificationDate = new Date(ExternalizableUtil.getInstance().readLong(in));
     }
+
+	public String getUID() {
+		return username;
+	}
 }

src/java/org/jivesoftware/util/rsm/Result.java

+package org.jivesoftware.util.rsm;
+
+/**
+ * Elements from a result set as defined by XEP-0059 have certain
+ * characteristics. This interface defines these characteristics.
+ * 
+ * Applying this interface to a class will allow you to use ResultSet operations
+ * on collections of your class. In other words: you are making collections of
+ * your class managable/navigable.
+ * 
+ * @author Guus der Kinderen, guus@nimbuzz.com
+ * @see http://www.xmpp.org/extensions/xep-0059.html
+ */
+public interface Result {
+
+	/**
+	 * Returns a unique identifier for this Result. Each element in a ResultSet
+	 * must have a distinct UIDs. 
+	 * 
+	 * XEP-0059 says: <quote>(...) the UIDs are
+	 * unique in the context of all possible members of the full result set.
+	 * Each UID MAY be based on part of the content of its associated item (...)
+	 * or on an internal table index. Another possible method is to serialize
+	 * the XML of the item and then hash it to generate the UID. Note: The
+	 * requesting entity MUST treat all UIDs as opaque.</quote>
+	 * 
+	 * @return Unique ID of the Result
+	 */
+	public String getUID();
+
+}
\ No newline at end of file

src/java/org/jivesoftware/util/rsm/ResultSetImpl.java

+package org.jivesoftware.util.rsm;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.Hashtable;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * A result set representation as described in XEP-0059. Note that this result
+ * 'set' actually makes use of a List implementations, as the Java Set
+ * definition disallows duplicate elements, while the List definition supplies
+ * most of the required indexing operations.
+ * 
+ * This ResultSet implementation loads all all results from the set into memory,
+ * which might be undesirable for very large sets, or for sets where the
+ * retrieval of a result is an expensive operation. sets.
+ * 
+ * As most methods are backed by the {@link List#subList(int, int)} method,
+ * non-structural changes in the returned lists are reflected in the ResultSet,
+ * and vice-versa.
+ * 
+ * @author Guus der Kinderen, guus@nimbuzz.com
+ * 
+ * @param <E>
+ *            Each result set should be a collection of instances of the exact
+ *            same class. This class must implement the {@link Result}
+ *            interface.
+ * @see java.util.List#subList(int, int)
+ * 
+ */
+/*
+ * TODO: do we want changes to the returned Lists of methods in this class be
+ * applied to the content of the ResultSet itself? Currently, because of the
+ * usage of java.util.List#subList(int, int), it does. I'm thinking a
+ * immodifiable solution would cause less problems. -Guus
+ */
+public class ResultSetImpl<E extends Result> extends ResultSet<E> {
+
+	/**
+	 * A list of all results in this ResultSet
+	 */
+	public final List<E> resultList;
+
+	/**
+	 * A mapping of the UIDs of all results in resultList, to the index of those
+	 * entries in that list.
+	 */
+	public final Map<String, Integer> uidToIndex;
+
+	/**
+	 * Creates a new Result Set instance, based on a collection of Result
+	 * implementing objects. The collection should contain elements of the exact
+	 * same class only, and cannot contain 'null' elements.
+	 * 
+	 * The order that's being used in the new ResultSet instance is the same
+	 * order in which {@link Collection#iterator()} iterates over the
+	 * collection.
+	 * 
+	 * Note that this constructor throws an IllegalArgumentException if the
+	 * Collection that is provided contains Results that have duplicate UIDs.
+	 * 
+	 * @param results
+	 *            The collection of Results that make up this result set.
+	 */
+	public ResultSetImpl(Collection<E> results) {
+		this(results, null);
+	}
+
+	/**
+	 * Creates a new Result Set instance, based on a collection of Result
+	 * implementing objects. The collection should contain elements of the exact
+	 * same class only, and cannot contain 'null' elements.
+	 * 
+	 * The order that's being used in the new ResultSet instance is defined by
+	 * the supplied Comparator class.
+	 * 
+	 * Note that this constructor throws an IllegalArgumentException if the
+	 * Collection that is provided contains Results that have duplicate UIDs.
+	 * 
+	 * @param results
+	 *            The collection of Results that make up this result set.
+	 * @param comparator
+	 *            The Comparator that defines the order of the Results in this
+	 *            result set.
+	 */
+	public ResultSetImpl(Collection<E> results, Comparator<E> comparator) {
+		if (results == null) {
+			throw new NullPointerException("Argument 'results' cannot be null.");
+		}
+
+		final int size = results.size();
+		resultList = new ArrayList<E>(size);
+		uidToIndex = new Hashtable<String, Integer>(size);
+
+		// sort the collection, if need be.
+		List<E> sortedResults = null;
+		if (comparator != null) {
+			sortedResults = new ArrayList<E>(results);
+			Collections.sort(sortedResults, comparator);
+		}
+
+		int index = 0;
+		// iterate over either the sorted or unsorted collection
+		for (final E result : (sortedResults != null ? sortedResults : results)) {
+			if (result == null) {
+				throw new NullPointerException(
+						"The result set must not contain 'null' elements.");
+			}
+
+			final String uid = result.getUID();
+			if (uidToIndex.containsKey(uid)) {
+				throw new IllegalArgumentException(
+						"The result set can not contain elements that have the same UID.");
+			}
+
+			resultList.add(result);
+			uidToIndex.put(uid, Integer.valueOf(index));
+			index++;
+		}
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#size()
+	 */
+	@Override
+	public int size() {
+		return resultList.size();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#getAfter(E, int)
+	 */
+	@Override
+	public List<E> getAfter(String uid, int maxAmount) {
+		if (uid == null || uid.length() == 0) {
+			throw new NullPointerException("Argument 'uid' cannot be null or an empty String.");
+		}
+
+		if (maxAmount < 1) {
+			throw new IllegalArgumentException(
+					"Argument 'maxAmount' must be a integer higher than zero.");
+		}
+
+		// the result of this method is exclusive 'result'
+		final int index = uidToIndex.get(uid) + 1;
+
+		return get(index, maxAmount);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#getBefore(E, int)
+	 */
+	@Override
+	public List<E> getBefore(String uid, int maxAmount) {
+		if (uid == null || uid.length() == 0) {
+			throw new NullPointerException("Argument 'uid' cannot be null or an empty String.");
+		}
+
+		if (maxAmount < 1) {
+			throw new IllegalArgumentException(
+					"Argument 'maxAmount' must be a integer higher than zero.");
+		}
+
+		// the result of this method is exclusive 'result'
+		final int indexOfLastElement = uidToIndex.get(uid);
+		final int indexOfFirstElement = indexOfLastElement - maxAmount;
+
+		if (indexOfFirstElement < 0) {
+			return get(0, indexOfLastElement);
+		}
+
+		return get(indexOfFirstElement, maxAmount);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#get(int)
+	 */
+	@Override
+	public E get(int index) {
+		return resultList.get(index);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#getFirst(int)
+	 */
+	@Override
+	public List<E> getFirst(int maxAmount) {
+		if (maxAmount < 1) {
+			throw new IllegalArgumentException(
+					"Argument 'maxAmount' must be a integer higher than zero.");
+		}
+
+		return get(0, maxAmount);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#getLast(int)
+	 */
+	@Override
+	public List<E> getLast(int maxAmount) {
+		if (maxAmount < 1) {
+			throw new IllegalArgumentException(
+					"Argument 'maxAmount' must be a integer higher than zero.");
+		}
+
+		final int indexOfFirstElement = size() - maxAmount;
+
+		if (indexOfFirstElement < 0) {
+			return get(0, maxAmount);
+		}
+
+		return get(indexOfFirstElement, maxAmount);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.buzzaa.xmpp.resultsetmanager.ResultSet#get(int, int)
+	 */
+	@Override
+	public List<E> get(int fromIndex, int maxAmount) {
+		if (fromIndex < 0) {
+			throw new IllegalArgumentException(
+					"Argument 'fromIndex' must be zero or higher.");
+		}
+
+		if (maxAmount < 1) {
+			throw new IllegalArgumentException(
+					"Argument 'maxAmount' must be a integer higher than zero.");
+		}
+
+		if (fromIndex >= size()) {
+			return new ArrayList<E>(0);
+		}
+
+		// calculate the last index to return, or return up to the end of last
+		// index if 'amount' surpasses the list length.
+		final int absoluteTo = fromIndex + maxAmount;
+		final int toIndex = (absoluteTo > size() ? size() : absoluteTo);
+
+		return resultList.subList(fromIndex, toIndex);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.jivesoftware.util.resultsetmanager.ResultSet#indexOf(java.lang.String)
+	 */
+	@Override
+	public int indexOf(String uid) {
+		return uidToIndex.get(uid).intValue();
+	}
+}

src/plugins/search/changelog.html

@@ -44,6 +44,11 @@
 Search Plugin Changelog
 </h1>
 
+<p><b>1.4.2</b> -- XXX</p>
+<ul>
+    <li>Implemented XEP-0059 "Result Set Management".</li>
+</ul>
+
 <p><b>1.4.1</b> -- June 20, 2007</p>
 <ul>
     <li>Unescape username before returning search results to the client.</li>