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Class com.oroinc.net.CharGenUDPClient
java.lang.Object
|
+----com.oroinc.net.DatagramSocketClient
|
+----com.oroinc.net.CharGenUDPClient
- public final class CharGenUDPClient
- extends DatagramSocketClient
The CharGenUDPClient class is a UDP implementation of a client for the
character generator protocol described in RFC 864. It can also be
used for Systat (RFC 866), Quote of the Day (RFC 865), and netstat
(port 15). All of these protocols involve sending a datagram to the
appropriate port, and reading data contained in one or more reply
datagrams. The chargen and quote of the day protocols only send
one reply datagram containing 512 bytes or less of data. The other
protocols may reply with more than one datagram, in which case you
must wait for a timeout to determine that all reply datagrams have
been sent.
To use the CharGenUDPClient class, just open a local UDP port
with open
and call send to send the datagram that will
initiate the data reply. For chargen or quote of the day, just
call receive , and you're done. For netstat and
systat, call receive in a while loop, and catch a SocketException and
InterruptedIOException to detect a timeout (don't forget to set the
timeout duration beforehand). Don't forget to call
close()
to clean up properly.
Copyright © 1997 Original Reusable Objects, Inc.
All rights reserved.
- See Also:
- CharGenTCPClient
-
CHARGEN_PORT
- The character generator port value of 19 according to RFC 864.
-
DEFAULT_PORT
- The default chargen port.
-
NETSTAT_PORT
- The netstat port value of 19.
-
QUOTE_OF_DAY_PORT
- The quote of the day port value of 17 according to RFC 865.
-
SYSTAT_PORT
- The systat port value of 11 according to RFC 866.
-
CharGenUDPClient()
- The default CharGenUDPClient constructor.
-
receive()
- Receive the reply data from the server.
-
send(InetAddress)
- Same as
send(host, CharGenUDPClient.DEFAULT_PORT);
-
send(InetAddress, int)
- Sends the data initiation datagram.
SYSTAT_PORT
public static final int SYSTAT_PORT
- The systat port value of 11 according to RFC 866.
NETSTAT_PORT
public static final int NETSTAT_PORT
- The netstat port value of 19.
QUOTE_OF_DAY_PORT
public static final int QUOTE_OF_DAY_PORT
- The quote of the day port value of 17 according to RFC 865.
CHARGEN_PORT
public static final int CHARGEN_PORT
- The character generator port value of 19 according to RFC 864.
DEFAULT_PORT
public static final int DEFAULT_PORT
- The default chargen port. It is set to 19 according to RFC 864.
CharGenUDPClient
public CharGenUDPClient()
- The default CharGenUDPClient constructor. It initializes some internal
data structures for sending and receiving the necessary datagrams for
the chargen and related protocols.
send
public void send(InetAddress host,
int port) throws IOException
- Sends the data initiation datagram. This data in the packet is ignored
by the server, and merely serves to signal that the server should send
its reply.
- Parameters:
- host - The address of the server.
- port - The port of the service.
- Throws: IOException
- If an error occurs while sending the datagram.
send
public void send(InetAddress host) throws IOException
- Same as
send(host, CharGenUDPClient.DEFAULT_PORT);
receive
public byte[] receive() throws IOException
- Receive the reply data from the server. This will always be 512 bytes
or less. Chargen and quote of the day only return one packet. Netstat
and systat require multiple calls to receive() with timeout detection.
- Returns:
- The reply data from the server.
- Throws: IOException
- If an error occurs while receiving the datagram.
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