| window.runtime property | window.runtime.flash.net.DatagramSocket |
| Inheritance | DatagramSocket  EventDispatcher Object |
| Runtime Versions: | 2 |
Datagram packets are individually transmitted between the source and destination. Packets can arrive in a different order than they were sent. Packets lost in transmission are not retransmitted, or even detected.
Data sent using a datagram socket is not automatically broken up into packets of transmittable size. If you send a UDP packet that exceeds the maximum transmission unit (MTU) size, network discards the packet (without warning). The limiting MTU is the smallest MTU of any interface, switch, or router in the transmission path. You can use the NetworkInterface class to determine the MTU of the local interface, but other nodes in the network can have different MTU values.
The Socket class uses TCP which provides guaranteed packet delivery and automatically divides and reassembles large packets. TCP also provides better network bandwidth management. These features mean that data sent using a TCP socket incurs higher latency, but for most uses, the benefits of TCP far outweigh the costs. Most network communication should use the Socket class rather than the DatagramSocket class.
The DatagramSocket class is useful for working with applications where a small transmission latency is important and packet loss is tolerable. For example, network operations in voice-over-IP (VoIP) applications and real-time, multiplayer games can often benefit from UDP. The DatagramSocket class is also useful for some server-side applications. Since UDP is a stateless protocol, a server can handle more requests from more clients than it can with TCP.
The DatagramSocket class can only be used in Adobe AIR applications and only in the application security sandbox.
For more information related to security, see the Flash Player Developer Center Topic: Security.
See also
Hide Inherited Public Properties
Show Inherited Properties| Property | Defined By | ||
|---|---|---|---|
| bound : Boolean [read-only]
Indicates whether this socket object is currently bound to a local address
and port. | DatagramSocket | ||
| connected : Boolean [read-only]
Indicates whether this socket object is currently connected to a remote address
and port. | DatagramSocket | ||
 | constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | |
| isSupported : Boolean [static] [read-only]
Indicates whether or not DatagramSocket features are supported in the run-time environment. | DatagramSocket | ||
| localAddress : String [read-only]
The IP address this socket is bound to on the local machine. | DatagramSocket | ||
| localPort : int [read-only]
The port this socket is bound to on the local machine. | DatagramSocket | ||
| prototype : Object [static]
A reference to the prototype object of a class or function object. | Object | |
| remoteAddress : String [read-only]
The IP address of the remote machine to which this socket is connected. | DatagramSocket | ||
| remotePort : int [read-only]
The port on the remote machine to which this socket is connected. | DatagramSocket | ||
| Method | Defined By | ||
|---|---|---|---|
Creates a DatagramSocket object. | DatagramSocket | ||
| addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener
receives notification of an event. | EventDispatcher | |
bind(localPort:int = 0, localAddress:String = "0.0.0.0"):void
Binds this socket to the specified local address and port. | DatagramSocket | ||
close():void
Closes the socket. | DatagramSocket | ||
connect(remoteAddress:String, remotePort:int):void
Connects the socket to a specified remote address and port. | DatagramSocket | ||
| dispatchEvent(event:Event):Boolean
Dispatches an event into the event flow. | EventDispatcher | |
| hasEventListener(type:String):Boolean
Checks whether the EventDispatcher object has any listeners registered for a specific type
of event. | EventDispatcher | |
| hasOwnProperty(name:String):Boolean
Indicates whether an object has a specified property defined. | Object | |
| isPrototypeOf(theClass:Object):Boolean
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | |
| propertyIsEnumerable(name:String):Boolean
Indicates whether the specified property exists and is enumerable. | Object | |
receive():void
Enables this DatagramSocket object to receive incoming packets on the bound IP address and port. | DatagramSocket | ||
| removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object. | EventDispatcher | |
Sends packet containing the bytes in the ByteArray using UDP. | DatagramSocket | ||
| setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void
Sets the availability of a dynamic property for loop operations. | Object | |
| toLocaleString():String
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | |
| toString():String
Returns the string representation of the specified object. | Object | |
| valueOf():Object
Returns the primitive value of the specified object. | Object | |
| willTrigger(type:String):Boolean
Checks whether an event listener is registered with this EventDispatcher object or any of
its ancestors for the specified event type. | EventDispatcher | |
| Event | Summary | Defined By | ||
|---|---|---|---|---|
| [broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active. | EventDispatcher | ||
| Dispatched when the operating system closes this socket. | DatagramSocket | |||
| Dispatched when this socket receives a packet of data. | DatagramSocket | |||
| [broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive. | EventDispatcher | ||
| Dispatched when this socket receives an I/O error. | DatagramSocket | |||
bound | property |
bound:Boolean [read-only] | Runtime Versions: | 2 |
Indicates whether this socket object is currently bound to a local address and port.
See also
connected | property |
connected:Boolean [read-only] | Runtime Versions: | 2 |
Indicates whether this socket object is currently connected to a remote address and port.
Note: A value of true does not mean that a remote computer
is listening on the connected address and port. It only means that this DataGramSocket object
will only send data to or receive data from that address and port.
See also
isSupported | property |
isSupported:Boolean [read-only] | Runtime Versions: | 2 |
Indicates whether or not DatagramSocket features are supported in the run-time environment.
localAddress | property |
localAddress:String [read-only] | Runtime Versions: | 2 |
The IP address this socket is bound to on the local machine.
See also
localPort | property |
localPort:int [read-only] | Runtime Versions: | 2 |
The port this socket is bound to on the local machine.
See also
remoteAddress | property |
remoteAddress:String [read-only] | Runtime Versions: | 2 |
The IP address of the remote machine to which this socket is connected.
See also
remotePort | property |
remotePort:int [read-only] | Runtime Versions: | 2 |
The port on the remote machine to which this socket is connected.
See also
DatagramSocket | () | Constructor |
public function DatagramSocket()| Runtime Versions: | 2 |
Creates a DatagramSocket object.
Throws
SecurityError — if content outside the AIR application security
sandbox attempts to create a DatagramSocket object.
|
bind | () | method |
public function bind(localPort:int = 0, localAddress:String = "0.0.0.0"):void| Runtime Versions: | 2 |
Binds this socket to the specified local address and port.
The bind() method executes synchronously. The bind operation completes
before the next line of code is executed.
Parameters
localPort:int (default = 0)localPort,
is set to 0 (the default), the next available system port is bound. Permission to connect to a port
number below 1024 is subject to the system security policy. On Mac and Linux systems, for example,
the application must be running with root privileges to connect to ports below 1024.
| |
localAddress:String (default = "0.0.0.0")localAddress is set to 0.0.0.0 (the default),
the socket listens on all available IPv4 addresses.
To listen on all available IPv6 addresses, you must specify "::" as the localAddress
argument. To use an IPv6 address, the computer and network must both be
configured to support IPv6. Furthermore, a socket bound to an IPv4 address
cannot connect to a socket with an IPv6 address. Likewise, a socket bound to an IPv6
address cannot connect to a socket with an IPv4 address. The type of address must match.
|
Throws
RangeError — This error occurs when localPort is less than 0 or greater than 65535.
| |
ArgumentError — This error occurs when localAddress is not a syntactically well-formed IP address.
| |
IOError — This error occurs if the socket cannot be bound, such as when:
| |
Error — This error occurs when localAddress is not a valid local address.
|
Example ( How to use this example )
udpSocket.bind(); //bind to any available port, listen on all IPv4 addresses udpSocket.bind( 0, "0.0.0.0" ); //same as above udpSocket.bind( 0, "127.0.0.1" ); //any available port on the localhost address udpSocket.bind( 8989, "192.168.0.1" ); //port 8989 on a particular IPv4 address udpSocket.bind( 0, "::" ); //any available port on all IPv6 address udpSocket.bind( 8989, "::1" ); //port 8989 on the IPv6 localhost address udpSocket.bind( 8989, "2001:1890:110b:1e19:f06b:72db:7026:3d7a" ); //port 8989 on a particular IPv6 address
close | () | method |
public function close():void| Runtime Versions: | 2 |
Closes the socket.
The socket is disconnected from the remote machine and unbound from the local machine. A closed socket cannot be reused.
Throws
IOError — If the socket cannot be closed (because of an internal, networking,
or operating system error), or if the socket is not open.
|
connect | () | method |
public function connect(remoteAddress:String, remotePort:int):void| Runtime Versions: | 2 |
Connects the socket to a specified remote address and port.
When a datagram socket is "connected," datagram packets can only be sent to and received from the specified target. Packets from other sources are ignored. Connecting a datagram socket is not required. Establishing a connection can remove the need to filter out extraneous packets from other sources. However, a UDP socket connection is not a persistent network connection (as it is for a TCP connection). It is possible that the remote end of the socket does not even exist.
If the bind() method has not been called, the socket is
automatically bound to the default local address and port.
Parameters
remoteAddress:String — The IP address of the remote machine with which to establish
a connection. This address can be an IPv4 or IPv6 address. If bind() has not
been called, the address family of the remoteAddress, IPv4 or IPv6, is used when calling the
default bind().
| |
remotePort:int — The port number on the remote machine used to establish a connection.
|
Throws
RangeError — This error occurs when localPort is less than 1 or greater than 65535.
| |
ArgumentError — This error occurs when localAddress is not a syntactically valid address.
Or when a default route address ('0.0.0.0' or '::') is used.
| |
IOError — This error occurs if the socket cannot be connected, such as when bind() has not
been called before the call to connect() and default binding to the remote address family is not possible.
|
receive | () | method |
public function receive():void| Runtime Versions: | 2 |
Enables this DatagramSocket object to receive incoming packets on the bound IP address and port.
The function returns immediately. The DatagramSocket object dispatches a data event
when a data packet is received.
Events
data: — when a UDP packet is received. |
send | () | method |
public function send(bytes:ByteArray, offset:uint = 0, length:uint = 0, address:String = null, port:int = 0):void| Runtime Versions: | 2 |
Sends packet containing the bytes in the ByteArray using UDP.
If the socket is connected, the packet
is sent to the remote address and port specified in the connect()
method and no destination IP address and port can be specified. If the socket is
not connected, the packet is sent to the specified address and port
and you must supply valid values for address and port.
If the bind() method has not been called, the socket is
automatically bound to the default local address and port.
Note: Sending data to a broadcast address is not supported.
Parameters
bytes:ByteArray — a ByteArray containing the packet data.
| |
offset:uint (default = 0)bytes ByteArray
object at which the packet begins.
| |
length:uint (default = 0)offset parameter.
| |
address:String (default = null)connect() method.
| |
port:int (default = 0)connect() method.
|
Throws
RangeError — This error occurs when port is less than 1 or greater than 65535.
| |
ArgumentError — If the socket is not connected and address is not a well-formed IP address.
| |
IOError — This error occurs:
| |
Error — when the bytes parameter is null.
| |
RangeError — If offset is greater than the length of the ByteArray specified in
bytes or if the amount of data specified to be written by offset plus
length exceeds the data available.
| |
IllegalOperationError — If the address or port parameters are specified
when the socket has already been connected.
|
close | Event |
flash.events.Eventproperty Event.type =
flash.events.Event.CLOSE| Runtime Versions: | 2 |
Dispatched when the operating system closes this socket.
The close event is not dispatched when the DatagramSocket close()
method is called.
Event.CLOSE constant defines the value of the type property of a close event object.
This event has the following properties:
| Property | Value |
|---|---|
bubbles | false |
cancelable | false; there is no default behavior to cancel. |
currentTarget | The object that is actively processing the Event object with an event listener. |
target | The object whose connection has been closed. |
data | Event |
flash.events.DatagramSocketDataEventproperty DatagramSocketDataEvent.type =
flash.events.DatagramSocketDataEvent.DATA| Runtime Versions: | 2 |
Dispatched when this socket receives a packet of data.
Defines the value of thetype property of a data event object.
ioError | Event |
flash.events.IOErrorEventproperty IOErrorEvent.type =
flash.events.IOErrorEvent.IOERROR| Runtime Versions: | 2.5 |
Dispatched when this socket receives an I/O error.
<html>
<head>
<title>DNSResolver Example</title>
<script src="AIRAliases.js"></script>
<script>
var datagramSocket = new air.DatagramSocket();
var localIP;
var localPort;
var logField;
var targetIP;
var targetPort;
var message;
function init()
{
localIP = document.getElementById("localIP");
localPort = document.getElementById("localPort");
targetIP = document.getElementById("targetIP");
targetPort = document.getElementById("targetPort");
message = document.getElementById("message");
logField = document.getElementById("logField");
}
function bind( event )
{
if( datagramSocket.bound )
{
datagramSocket.close();
datagramSocket = new air.DatagramSocket();
}
datagramSocket.bind( parseInt( localPort.text ), localIP.text );
datagramSocket.addEventListener( air.DatagramSocketDataEvent.DATA, dataReceived );
datagramSocket.receive();
log( "Bound to: " + datagramSocket.localAddress + ":" + datagramSocket.localPort );
}
function dataReceived( event )
{
//Read the data from the datagram
log("Received from " + event.srcAddress + ":" + event.srcPort + "> " +
event.data.readUTFBytes( event.data.bytesAvailable ) );
}
function send( event )
{
//Send a datagram to the target
try
{
//Create a message in a ByteArray
var data = new air.ByteArray();
data.writeUTFBytes( message.value );
datagramSocket.send( data, 0, 0, targetIP.value, targetPort.value );
log( "Sent message to " + targetIP.value + ":" + targetPort.value );
}
catch ( error )
{
log( error.message );
}
}
function log( text )
{
logField.value += text + "\n";
air.trace( text );
}
</script>
<body onload="init()">
Local IP <input type="text" id="localIP" value="0.0.0.0"/>
Port <input type="text" id="localPort" size="5" value="0"/>
<button onclick="bind()">Bind</button><br/>
<hr/>
Remote IP <input type="text" id="targetIP" value="127.0.0.1"/>
Port <input type="text" id="targetPort" size="5" value="8989"/> <br/>
Message <input type="text" id="message" size="30" value="Lucy can't drink milk."/>
<button onclick="send()">Send</button><br/>
<textarea id="logField" cols="80" rows="40" title="Log"></textarea>
</body>
</html>Thu Sep 29 2011, 02:34 AM -07:00