Remove duplicate code in pubusb LeafNode

Make fields of GetItemsRequest and NodeExtension final and use
XmlStringBuilder.

smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/GetItemsRequest.java

@@ -16,36 +16,37 @@
  */
 package org.jivesoftware.smackx.pubsub;
 
+import org.jivesoftware.smack.util.XmlStringBuilder;
+
 /**
  * Represents a request to subscribe to a node.
  * 
  * @author Robin Collier
  */
 public class GetItemsRequest extends NodeExtension
 {
-	protected String subId;
-	protected int maxItems;
+	protected final String subId;
+	protected final int maxItems;
 
 	public GetItemsRequest(String nodeId)
 	{
-		super(PubSubElementType.ITEMS, nodeId);
+		this(nodeId, null, -1);
 	}
 
 	public GetItemsRequest(String nodeId, String subscriptionId)
 	{
-		super(PubSubElementType.ITEMS, nodeId);
-		subId = subscriptionId;
+        this(nodeId, subscriptionId, -1);
 	}
 
 	public GetItemsRequest(String nodeId, int maxItemsToReturn)
 	{
-		super(PubSubElementType.ITEMS, nodeId);
-		maxItems = maxItemsToReturn;
+        this(nodeId, null, maxItemsToReturn);
 	}
 
 	public GetItemsRequest(String nodeId, String subscriptionId, int maxItemsToReturn)
 	{
-		this(nodeId, maxItemsToReturn);
+        super(PubSubElementType.ITEMS, nodeId);
+        maxItems = maxItemsToReturn;
 		subId = subscriptionId;
 	}
 
@@ -60,29 +61,13 @@ public int getMaxItems()
 	}
 
 	@Override
-	public String toXML()
-	{
-		StringBuilder builder = new StringBuilder("<");
-		builder.append(getElementName());
-
-		builder.append(" node='");
-		builder.append(getNode());
-		builder.append("'");
-
-		if (getSubscriptionId() != null)
-		{
-			builder.append(" subid='");
-			builder.append(getSubscriptionId());
-			builder.append("'");
-		}
-
-		if (getMaxItems() > 0)
-		{
-			builder.append(" max_items='");
-			builder.append(getMaxItems());
-			builder.append("'");
-		}
-		builder.append("/>");
-		return builder.toString();
-	}
+    public XmlStringBuilder toXML() {
+        XmlStringBuilder xml = new XmlStringBuilder();
+        xml.halfOpenElement(getElementName());
+        xml.attribute("node", getNode());
+        xml.optAttribute("subid", getSubscriptionId());
+        xml.optIntAttribute("max_items", getMaxItems());
+        xml.closeEmptyElement();
+        return xml;
+    }
 }

smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/LeafNode.java

@@ -68,14 +68,10 @@ public DiscoverItems discoverItems() throws NoResponseException, XMPPErrorExcept
 	 * @throws NoResponseException if there was no response from the server.
 	 * @throws NotConnectedException 
 	 */
-	@SuppressWarnings("unchecked")
 	public <T extends Item> List<T> getItems() throws NoResponseException, XMPPErrorException, NotConnectedException
 	{
 		PubSub request = createPubsubPacket(Type.get, new GetItemsRequest(getId()));
-
-		PubSub result = (PubSub) con.createPacketCollectorAndSend(request).nextResultOrThrow();
-		ItemsExtension itemsElem = (ItemsExtension)result.getExtension(PubSubElementType.ITEMS);
-		return (List<T>)itemsElem.getItems();
+        return getItems(request);
 	}
 
 	/**
@@ -90,14 +86,10 @@ public <T extends Item> List<T> getItems() throws NoResponseException, XMPPError
 	 * @throws NoResponseException if there was no response from the server.
 	 * @throws NotConnectedException 
 	 */
-	@SuppressWarnings("unchecked")
 	public <T extends Item> List<T> getItems(String subscriptionId) throws NoResponseException, XMPPErrorException, NotConnectedException
 	{
 		PubSub request = createPubsubPacket(Type.get, new GetItemsRequest(getId(), subscriptionId));
-
-		PubSub result = (PubSub) con.createPacketCollectorAndSend(request).nextResultOrThrow();
-		ItemsExtension itemsElem = (ItemsExtension)result.getExtension(PubSubElementType.ITEMS);
-		return (List<T>)itemsElem.getItems();
+        return getItems(request);
 	}
 
 	/**
@@ -114,7 +106,6 @@ public <T extends Item> List<T> getItems(String subscriptionId) throws NoRespons
 	 * @throws NoResponseException if there was no response from the server.
 	 * @throws NotConnectedException 
 	 */
-	@SuppressWarnings("unchecked")
 	public <T extends Item> List<T> getItems(Collection<String> ids) throws NoResponseException, XMPPErrorException, NotConnectedException
 	{
 		List<Item> itemList = new ArrayList<Item>(ids.size());
@@ -124,10 +115,7 @@ public <T extends Item> List<T> getItems(Collection<String> ids) throws NoRespon
 			itemList.add(new Item(id));
 		}
 		PubSub request = createPubsubPacket(Type.get, new ItemsExtension(ItemsExtension.ItemsElementType.items, getId(), itemList));
-
-		PubSub result = (PubSub) con.createPacketCollectorAndSend(request).nextResultOrThrow();
-		ItemsExtension itemsElem = (ItemsExtension)result.getExtension(PubSubElementType.ITEMS);
-		return (List<T>)itemsElem.getItems();
+        return getItems(request);
 	}
 
 	/**
@@ -140,14 +128,10 @@ public <T extends Item> List<T> getItems(Collection<String> ids) throws NoRespon
 	 * @throws NoResponseException if there was no response from the server.
 	 * @throws NotConnectedException 
 	 */
-	@SuppressWarnings("unchecked")
 	public <T extends Item> List<T> getItems(int maxItems) throws NoResponseException, XMPPErrorException, NotConnectedException
 	{
 		PubSub request = createPubsubPacket(Type.get, new GetItemsRequest(getId(), maxItems));
-
-		PubSub result = (PubSub) con.createPacketCollectorAndSend(request).nextResultOrThrow();
-		ItemsExtension itemsElem = (ItemsExtension)result.getExtension(PubSubElementType.ITEMS);
-		return (List<T>)itemsElem.getItems();
+        return getItems(request);
 	}
 
 	/**
@@ -163,16 +147,19 @@ public <T extends Item> List<T> getItems(int maxItems) throws NoResponseExceptio
 	 * @throws NoResponseException if there was no response from the server.
 	 * @throws NotConnectedException 
 	 */
-	@SuppressWarnings("unchecked")
 	public <T extends Item> List<T> getItems(int maxItems, String subscriptionId) throws NoResponseException, XMPPErrorException, NotConnectedException
 	{
 		PubSub request = createPubsubPacket(Type.get, new GetItemsRequest(getId(), subscriptionId, maxItems));
-
-		PubSub result = (PubSub) con.createPacketCollectorAndSend(request).nextResultOrThrow();
-		ItemsExtension itemsElem = (ItemsExtension)result.getExtension(PubSubElementType.ITEMS);
-		return (List<T>)itemsElem.getItems();
+        return getItems(request);
 	}
-
+
+    @SuppressWarnings("unchecked")
+    private <T extends Item> List<T> getItems(PubSub request) throws NoResponseException, XMPPErrorException, NotConnectedException {
+        PubSub result = con.createPacketCollectorAndSend(request).nextResultOrThrow();
+        ItemsExtension itemsElem = result.getExtension(PubSubElementType.ITEMS);
+        return (List<T>) itemsElem.getItems();
+    }
+
 	/**
 	 * Publishes an event to the node.  This is an empty event
 	 * with no item.

smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/NodeExtension.java

@@ -28,8 +28,8 @@
  */
 public class NodeExtension implements PacketExtension
 {
-	private PubSubElementType element;
-	private String node;
+	private final PubSubElementType element;
+	private final String node;
 
 	/**
 	 * Constructs a <tt>NodeExtension</tt> with an element name specified

smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/packet/PubSub.java

@@ -18,6 +18,7 @@
 
 import org.jivesoftware.smack.packet.IQ;
 import org.jivesoftware.smack.packet.PacketExtension;
+import org.jivesoftware.smack.util.XmlStringBuilder;
 import org.jivesoftware.smackx.pubsub.PubSubElementType;
 
 /**
@@ -85,9 +86,10 @@ public void setPubSubNamespace(PubSubNamespace ns)
 		this.ns = ns;
 	}
 
-	public PacketExtension getExtension(PubSubElementType elem)
+    @SuppressWarnings("unchecked")
+    public <PE extends PacketExtension> PE getExtension(PubSubElementType elem)
 	{
-		return getExtension(elem.getElementName(), elem.getNamespace().getXmlns());
+		return (PE) getExtension(elem.getElementName(), elem.getNamespace().getXmlns());
 	}
 
 	/**
@@ -116,12 +118,13 @@ public PubSubNamespace getPubSubNamespace()
      * </pre>
      * 
      */
-    public String getChildElementXML() {
-        StringBuilder buf = new StringBuilder();
-        buf.append("<").append(getElementName()).append(" xmlns=\"").append(getNamespace()).append("\">");
-        buf.append(getExtensionsXML());
-        buf.append("</").append(getElementName()).append(">");
-        return buf.toString();
+    @Override
+    public XmlStringBuilder getChildElementXML() {
+        XmlStringBuilder xml = new XmlStringBuilder();
+        xml.halfOpenElement(getElementName()).xmlnsAttribute(getNamespace()).rightAngleBracket();
+        xml.append(getExtensionsXML());
+        xml.closeElement(getElementName());
+        return xml;
     }
 
     public static PubSub createPubsubPacket(String to, Type type, PacketExtension extension, PubSubNamespace ns) {