cgl.narada.service.time.ntptime
Class NtpHeader

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

public class NtpHeader
extends Object

This class encapsulates the header of a NtpDatagram. See rfc2030 for more details. 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |LI | VN |Mode | Stratum | Poll | Precision | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Root Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Root Dispersion | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reference Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Field Summary

static NtpHeader	defaultHeader The default header for a client datagram.
static byte[]	defaultHeaderData The default header data for a client datagram.

Constructor Summary

NtpHeader(byte[] data)
Construct a NtpHeader from a 16 byte array.

NtpHeader(int offset, byte[] data)
Construct a NtpHeader from a byte array and offset

Method Summary

byte[]	getHeaderData() Gets the 16 byte array constituting the header.
int	getLeapIndicator() Gets leap indicator
int	getMode() Gets mode
int	getPollInterval() Gets poll interval
double	getPrecision() Gets precision in milliseconds
String	getReferenceID() Gets ReferenceID using the stratum and version number of the packet.
String	getReferenceID(int stratumVal, int versionVal) Gets ReferenceID with the given stratum and version number.
double	getRootDelay() Gets root delay in milliseconds.
double	getRootDispersion() Gets root dispersion.
int	getStratum() Gets stratum
int	getVersionNumber() Gets version number

Methods inherited from class java.lang.Object

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

Field Detail

defaultHeaderData

public static final byte[] defaultHeaderData

The default header data for a client datagram. Version=3, Mode=client.

defaultHeader

public static final NtpHeader defaultHeader

The default header for a client datagram. This is a wrapper around defaultHeaderData

Constructor Detail

NtpHeader

public NtpHeader(byte[] data)

Construct a NtpHeader from a 16 byte array.

NtpHeader

public NtpHeader(int offset,
                 byte[] data)

Construct a NtpHeader from a byte array and offset

Method Detail

getHeaderData

public byte[] getHeaderData()

Gets the 16 byte array constituting the header.

Returns:

byte [] - header data

getLeapIndicator

public int getLeapIndicator()

Gets leap indicator

Returns:

int - leap indicator

getMode

public int getMode()

Gets mode

Returns:

int - mode

getPollInterval

public int getPollInterval()

Gets poll interval

Returns:

int - poll interval

getPrecision

public double getPrecision()

Gets precision in milliseconds

Returns:

double - precision

getReferenceID

public String getReferenceID(int stratumVal,
                             int versionVal)

Gets ReferenceID with the given stratum and version number.

Parameters:

stratumVal - stratum value of the server

versionVal - version number of the packet

Returns:

String - reference ID

getReferenceID

public String getReferenceID()

Gets ReferenceID using the stratum and version number of the packet.

Returns:

String - reference ID

getRootDelay

public double getRootDelay()

Gets root delay in milliseconds.

Returns:

double - root delay

getRootDispersion

public double getRootDispersion()

Gets root dispersion.

Returns:

double - root dispersion

getStratum

public int getStratum()

Gets stratum

Returns:

int - stratum

getVersionNumber

public int getVersionNumber()

Gets version number

Returns:

int - version number