cgl.narada.service.time.ntptime
Class NtpConnection

java.lang.Object
  cgl.narada.service.time.ntptime.NtpConnection

public class NtpConnection
extends Object

This class provides some methods to make UDP connection, send/receive NTP packets

Field Summary

static int

defaultNtpPort

Constructor Summary

NtpConnection(InetAddress iaddr)
Generates a UDP connection and sets the timeout to the default timeout value.

NtpConnection(InetAddress iaddr, int iport)
Generates a UDP connection and sets timeout to the socket

Method Summary

void	close() Closes the connection.
NtpInfo	getInfo() Exchanges NtpDatagramPacket with the server and generates NtpInfo object.
int	getTimeout() Gets the timeout of the connection.
NtpInfo	getTSInfo() This method is intended to be used with ClientDiscrepancy class.
void	receive(NtpDatagramPacket ntpDatagramPacket) Waits for a reply from the server.
void	receiveTS(NtpDatagramPacket ntpDatagramPacket, long offset11) This method is intended to be used with ClientDiscrepancy class.
void	send(NtpDatagramPacket ntpDatagramPacket) Sends NtpDatagramPacket to the server.
void	setBuffer(int start, int end, byte[] tbuffer, byte[] data) Sets buffer entries from start to end-1 with the given data array
void	setTimeout(int timeout) Sets the timeout of the asociated connection.

Methods inherited from class java.lang.Object

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

Field Detail

defaultNtpPort

public static final int defaultNtpPort

See Also:

Constant Field Values

Constructor Detail

NtpConnection

public NtpConnection(InetAddress iaddr,
                     int iport)
              throws SocketException

Generates a UDP connection and sets timeout to the socket

Parameters:

iaddr - InetAddress - InetAddress of the server

iport - int - port number of the server

Throws:

SocketException - - SocketException is thrown in case of failure

NtpConnection

public NtpConnection(InetAddress iaddr)
              throws SocketException

Generates a UDP connection and sets the timeout to the default timeout value.

Parameters:

iaddr - InetAddress - InetAddress of the server

Throws:

SocketException - - SocketException is thrown in case of failure

Method Detail

setBuffer

public void setBuffer(int start,
                      int end,
                      byte[] tbuffer,
                      byte[] data)

Sets buffer entries from start to end-1 with the given data array

Parameters:

start - int - start value

end - int - end value

tbuffer - byte[] - buffer

data - byte[] - data array to be copied

getInfo

public NtpInfo getInfo()
                throws IOException

Exchanges NtpDatagramPacket with the server and generates NtpInfo object.

Returns:

NtpInfo - NtpInfo object obtained from NTPDatagramPacket

Throws:

IOException - - IOException is thrown in case of socket timeout or connection failure

getTSInfo

public NtpInfo getTSInfo()
                  throws IOException

This method is intended to be used with ClientDiscrepancy class. Please do not use for other purposes. Returns NtpInfo.

Returns:

NtpInfo

Throws:

IOException

setTimeout

public void setTimeout(int timeout)
                throws SocketException

Sets the timeout of the asociated connection.

Parameters:

timeout - int - value of the timeout

Throws:

SocketException - - SocketException is thrown in case of connection failure

getTimeout

public int getTimeout()

Gets the timeout of the connection. The default timeout is 500 ms.

Returns:

int - timeout value

close

public void close()

Closes the connection.

receive

public void receive(NtpDatagramPacket ntpDatagramPacket)
             throws IOException

Waits for a reply from the server.

Parameters:

ntpDatagramPacket - NtpDatagramPacket - NtpDatagramPacket that will be set to the NtpDatagramPacket received from the server.

Throws:

IOException - - IOException is thrown in case of socket timeout or connection failure

receiveTS

public void receiveTS(NtpDatagramPacket ntpDatagramPacket,
                      long offset11)
               throws IOException

This method is intended to be used with ClientDiscrepancy class. Please do not use for other purposes. Receives NtpDatagramPacket and timestamps it with the adjusted time value.

Parameters:

ntpDatagramPacket -

offset11 - long - offset

Throws:

IOException

send

public void send(NtpDatagramPacket ntpDatagramPacket)
          throws IOException

Sends NtpDatagramPacket to the server.

Parameters:

ntpDatagramPacket - NtpDatagramPacket - NtpDatagramPacket that will be sent to the server.

Throws:

IOException - - IOException is thrown in case of connection failure