siena.comm
Class UDPPacketReceiver

java.lang.Object
  siena.comm.UDPPacketReceiver

All Implemented Interfaces:

PacketReceiver

public class UDPPacketReceiver
extends java.lang.Object
implements PacketReceiver

receives packets through a UDP port.

Field Summary

static int	AcceptPollingInterval controls the accept-close workaround.
static int	DefaultPort
static java.lang.String	Schema

Constructor Summary

UDPPacketReceiver(java.net.DatagramSocket s)

UDPPacketReceiver(int port_number)
create a receiver listening to the given UDP port.

Method Summary

byte[]	address() external address of this packet receiver.
protected static java.net.InetAddress	guessMyIPAddress()
protected static java.net.InetAddress	guessMyIPAddress(java.net.DatagramSocket s)
protected static java.net.InetAddress	guessMyIPAddress(java.net.ServerSocket s)
int	receive(byte[] buf) receives a packet in the given buffer.
int	receive(byte[] buf, long timeout) not yet implemented.
void	setHostName(java.lang.String hostname) explicitly set the address of this packet receiver.
void	shutdown() closes the receiver.
byte[]	uri() Deprecated. since 1.4.0. Please use address() instead.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface siena.comm.PacketReceiver

address, uri

Field Detail

Schema

public static final java.lang.String Schema

See Also:

Constant Field Values

DefaultPort

public static final int DefaultPort

See Also:

Constant Field Values

AcceptPollingInterval

public static int AcceptPollingInterval

controls the accept-close workaround. See TCPPacketReceiver.AcceptPollingInterval for an explanation of this parameter.

Constructor Detail

UDPPacketReceiver

public UDPPacketReceiver(int port_number)
                  throws java.io.IOException

create a receiver listening to the given UDP port.

Parameters:

port_number - must be a valid UDP port number, or it can be 0 in which case a random port is used

Throws:

java.io.IOException

UDPPacketReceiver

public UDPPacketReceiver(java.net.DatagramSocket s)
                  throws java.net.UnknownHostException,
                         java.io.IOException

Throws:

java.net.UnknownHostException

java.io.IOException

Method Detail

setHostName

public void setHostName(java.lang.String hostname)

explicitly set the address of this packet receiver. This method allows to set the host name or IP address explicitly. This might be necessary in the cases in which the java VM can not figure that out reliably.

shutdown

public void shutdown()

Description copied from interface: PacketReceiver

closes the receiver.

Specified by:

shutdown in interface PacketReceiver

receive

public int receive(byte[] buf)
            throws PacketReceiverException

Description copied from interface: PacketReceiver

receives a packet in the given buffer. This method must be reentrant. Siena clients and servers must be able to use several threads to receive packets from the same receiver.

Specified by:

receive in interface PacketReceiver

Returns:

the number of bytes read into the buffer. The return value must not be negative. On error conditions, this method must throw an exception.

Throws:

PacketReceiverException - in case an error occurrs while reading.

receive

public int receive(byte[] buf,
                   long timeout)

not yet implemented.

Specified by:

receive in interface PacketReceiver

Returns:

the number of bytes read into the buffer. The return value must not be negative. On error conditions, this method must throw an exception.

uri

public byte[] uri()

Deprecated. since 1.4.0. Please use address() instead.

This method has been replaced by address(). The reason for this change is more conceptual than practical: the term "address" is more appropriate than the term "uri" because it provides a way to reach a PacketReceiver, rather than an identifier.

address

public byte[] address()

external address of this packet receiver. Uses the following schema syntax:
schema:host:port

See Also:

PacketReceiver.address()

guessMyIPAddress

protected static java.net.InetAddress guessMyIPAddress()
                                                throws java.net.UnknownHostException

Throws:

java.net.UnknownHostException

guessMyIPAddress

protected static java.net.InetAddress guessMyIPAddress(java.net.ServerSocket s)
                                                throws java.net.UnknownHostException

Throws:

java.net.UnknownHostException

guessMyIPAddress

protected static java.net.InetAddress guessMyIPAddress(java.net.DatagramSocket s)
                                                throws java.net.UnknownHostException

Throws:

java.net.UnknownHostException