SMACK-403 add support for

XEP-0297 Stanza Forwarding and XEP-0280 Message Carbons
and
XEP-0297: Stanza Forwarding implementation

This patch adds Forwarded.java, a class to wrap messages forwarded
from a different entity. A forwarded stanza contains of a Packet and
an optional timestamp.

WARNING: The current implementation only allows to forward Message
packets, as there is no universal way to parse a Packet from SMACK.

XEP-0280 Message Carbons implementation

This patch adds Carbon.java, a class to wrap the packet extension
defined in XEP-0280 to store copies of messages sent to or received
by a user to his other client(s).

The CarbonManager allows to register XEP-0280 support with the SDM,
to enable and disable the feature and to manipulate messages
accordingly.

Signed-Off-By: Georg Lukas <georg@op-co.de>

git-svn-id: http://svn.igniterealtime.org/svn/repos/smack/trunk@13411 b35dd754-fafc-0310-a699-88a17e54d16e

source/org/jivesoftware/smackx/carbons/Carbon.java

@@ -0,0 +1,139 @@
+/**
+ * Copyright 2013 Georg Lukas
+ *
+ * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jivesoftware.smackx.carbons;
+
+import org.jivesoftware.smack.packet.Packet;
+import org.jivesoftware.smack.packet.PacketExtension;
+import org.jivesoftware.smack.provider.PacketExtensionProvider;
+import org.jivesoftware.smack.util.PacketParserUtils;
+import org.jivesoftware.smackx.forward.Forwarded;
+import org.jivesoftware.smackx.packet.DelayInfo;
+import org.jivesoftware.smackx.provider.DelayInfoProvider;
+import org.xmlpull.v1.XmlPullParser;
+
+/**
+ * Packet extension for XEP-0280: Message Carbons. This class implements
+ * the packet extension and a {@link PacketExtensionProvider} to parse
+ * message carbon copies from a packet. The extension
+ * <a href="http://xmpp.org/extensions/xep-0280.html">XEP-0280</a> is
+ * meant to synchronize a message flow to multiple presences of a user.
+ *
+ * <p>The {@link Carbon.Provider} must be registered in the
+ * <b>smack.properties</b> file for the elements <b>sent</b> and
+ * <b>received</b> with namespace <b>urn:xmpp:carbons:2</b></p> to be used.
+ *
+ * @author Georg Lukas
+ */
+public class Carbon implements PacketExtension {
+    public static final String NAMESPACE = "urn:xmpp:carbons:2";
+
+    private Direction dir;
+    private Forwarded fwd;
+
+    public Carbon(Direction dir, Forwarded fwd) {
+        this.dir = dir;
+        this.fwd = fwd;
+    }
+
+    /**
+     * get the direction (sent or received) of the carbon.
+     *
+     * @return the {@link Direction} of the carbon.
+     */
+    public Direction getDirection() {
+        return dir;
+    }
+
+    /**
+     * get the forwarded packet.
+     *
+     * @return the {@link Forwarded} message contained in this Carbon.
+     */
+    public Forwarded getForwarded() {
+        return fwd;
+    }
+
+    @Override
+    public String getElementName() {
+        return dir.toString();
+    }
+
+    @Override
+    public String getNamespace() {
+        return NAMESPACE;
+    }
+
+    @Override
+    public String toXML() {
+        StringBuilder buf = new StringBuilder();
+        buf.append("<").append(getElementName()).append(" xmlns=\"")
+                .append(getNamespace()).append("\">");
+
+        buf.append(fwd.toXML());
+
+        buf.append("</").append(getElementName()).append(">");
+        return buf.toString();
+    }
+
+    /**
+     * An enum to display the direction of a {@link Carbon} message.
+     */
+    public static enum Direction {
+        received,
+        sent
+    }
+
+    public static class Provider implements PacketExtensionProvider {
+
+        public PacketExtension parseExtension(XmlPullParser parser) throws Exception {
+            Direction dir = Direction.valueOf(parser.getName());
+            Forwarded fwd = null;
+
+            boolean done = false;
+            while (!done) {
+                int eventType = parser.next();
+                if (eventType == XmlPullParser.START_TAG && parser.getName().equals("forwarded")) {
+                    fwd = (Forwarded)new Forwarded.Provider().parseExtension(parser);
+                }
+                else if (eventType == XmlPullParser.END_TAG && dir == Direction.valueOf(parser.getName()))
+                    done = true;
+            }
+            if (fwd == null)
+                throw new Exception("sent/received must contain exactly one <forwarded> tag");
+            return new Carbon(dir, fwd);
+        }
+    }
+
+    /**
+     * Packet extension indicating that a message may not be carbon-copied.
+     */
+    public static class Private implements PacketExtension {
+        public static final String ELEMENT = "private";
+
+        public String getElementName() {
+            return ELEMENT;
+        }
+
+        public String getNamespace() {
+            return Carbon.NAMESPACE;
+        }
+
+        public String toXML() {
+            return "<" + ELEMENT + " xmlns=\"" + Carbon.NAMESPACE + "\"/>";
+        }
+    }
+}