87 lines
3.8 KiB
HTML
87 lines
3.8 KiB
HTML
<html>
|
|
<head>
|
|
<title>Smack: Processing Incoming Packets - Jive Software</title>
|
|
<link rel="stylesheet" type="text/css" href="style.css" />
|
|
</head>
|
|
|
|
<body>
|
|
|
|
<div class="header">
|
|
Processing Incoming Packets
|
|
</div>
|
|
|
|
<div class="nav">
|
|
« <a href="index.html">Table of Contents</a>
|
|
</div>
|
|
|
|
<p>
|
|
|
|
Smack provides a flexible framework for processing incoming packets using two constructs:
|
|
<ul>
|
|
<li><tt>org.jivesoftware.smack.PacketCollector</tt> -- a class that lets you
|
|
synchronously wait for new packets.
|
|
<li><tt>org.jivesoftware.smack.PacketListener</tt> -- an interface for asynchronously
|
|
notifying you of incoming packets.
|
|
</ul>
|
|
A packet listener is used for event style programming, while a packet collector has a
|
|
result queue of packets that you can do polling and blocking operations on. So, a packet
|
|
listener is useful when you want to take some action whenever a packet happens to come in,
|
|
while a packet collector is useful when you want to wait for a specific packet to
|
|
arrive. Packet collectors and listeners can be created using an <tt>XMPPConnection</tt> instance.<p>
|
|
|
|
The <tt>org.jivesoftware.smack.filter.PacketFilter</tt> interface determines which
|
|
specific packets will be delivered to a <tt>PacketCollector</tt> or <tt>PacketListener</tt>.
|
|
Many pre-defined filters can be found in the <tt>org.jivesoftware.smack.filter</tt> package.
|
|
|
|
<p>
|
|
The following code snippet demonstrates registering both a packet collector and a packet
|
|
listener:<p>
|
|
|
|
<div class="code"><pre>
|
|
<font color="gray"><i>// Create a packet filter to listen for new messages from a particular</i></font>
|
|
<font color="gray"><i>// user. We use an AndFilter to combine two other filters.</i></font>
|
|
PacketFilter filter = new AndFilter(new PacketTypeFilter(<b>Message.class</b>),
|
|
new FromContainsFilter(<font color="green">"mary@jivesoftware.com"</font>));
|
|
<font color="gray"><i>// Assume we've created a XMPPConnection name "connection".</i></font>
|
|
|
|
<font color="gray"><i>// First, register a packet collector using the filter we created.</i></font>
|
|
PacketCollector myCollector = connection.createPacketCollector(filter);
|
|
<font color="gray"><i>// Normally, you'd do something with the collector, like wait for new packets.</i></font>
|
|
|
|
<font color="gray"><i>// Next, create a packet listener. We use an anonymous inner class for brevity.</i></font>
|
|
PacketListener myListener = new PacketListener() {
|
|
<b>public</b> <b>void</b> processPacket(Packet packet) {
|
|
<font color="gray"><i>// Do something with the incoming packet here.</i></font>
|
|
}
|
|
};
|
|
<font color="gray"><i>// Register the listener.</i></font>
|
|
connection.addPacketListener(myListener, filter);
|
|
</pre></div><p>
|
|
|
|
<p class="subheader">
|
|
Standard Packet Filters
|
|
</p>
|
|
|
|
A rich set of packet filters are included with Smack, or you can create your own filters by coding
|
|
to the <tt>PacketFilter</tt> interface. The default set of filters includes:
|
|
<ul>
|
|
<li> <tt>PacketTypeFilter</tt> -- filters for packets that are a particular Class type.
|
|
<li> <tt>PacketIDFilter</tt> -- filters for packets with a particular packet ID.
|
|
<li> <tt>ThreadFilter</tt> -- filters for message packets with a particular thread ID.
|
|
<li> <tt>ToContainsFilter</tt> -- filters for packets that are sent to a particular address.
|
|
<li> <tt>FromContainsFilter</tt> -- filters for packets that are sent to a particular address.
|
|
<li> <tt>PacketExtensionFilter</tt> -- filters for packets that have a particular packet extension.
|
|
<li> <tt>AndFilter</tt> -- implements the logical AND operation over two filters.
|
|
<li> <tt>OrFilter</tt> -- implements the logical OR operation over two filters.
|
|
<li> <tt>NotFilter</tt> -- implements the logical NOT operation on a filter.
|
|
</ul>
|
|
|
|
|
|
|
|
<br clear="all" /><br><br>
|
|
<div class="footer">
|
|
Copyright © Jive Software 2002-2008
|
|
</div>
|
|
|
|
</body>
|
|
</html> |