com.antelmann.calendar
Class NTPClient

java.lang.Object
  com.antelmann.calendar.AbstractTimeSystem
      com.antelmann.calendar.NTPClient

All Implemented Interfaces:

TimeSystem

public class NTPClient
extends AbstractTimeSystem

implements a simple client for the Network Time Protocol (NTP).

Author:

Holger Antelmann

See Also:

NTPTime

Field Summary

static int	DEFAULT_PORT 123
static String	DEFAULT_SERVER_KEY key to obtain the default server via Settings.getProperty(String)
static String	DEFAULT_SERVER_LIST_KEY key to obtain the default server list via Settings.getProperty(String)
static double	TIME_OFFSET seconds between Jan-01-1990 and Jan-01-1970

Fields inherited from interface com.antelmann.calendar.TimeSystem

SYSTEM_TIME

Constructor Summary

NTPClient()

NTPClient(String serverName)

NTPClient(String serverName, int port)

Method Summary

protected long	aquireDelta() returns the current difference between system time and the time of this implementation in milliseconds.
static String	getDefaultServer()
static String[]	getDefaultServerList()
int	getPort()
String	getServer()
int	getTimeout()
static void	setDefaultServer(String server)
static void	setDefaultServerList(String... serverList)
void	setPort(int port)
void	setServer(String serverName)
void	setTimeout(int timeout)
String	toString()

Methods inherited from class com.antelmann.calendar.AbstractTimeSystem

adjustDelta, adjustedTimeMills, createTimerTask, currentTimeMillis, getDelta, getLastDeltaAdjustmentTime, getLastRoundTripDelay, setDelta, setLastRoundTripDelay

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_SERVER_KEY

public static final String DEFAULT_SERVER_KEY

key to obtain the default server via Settings.getProperty(String)

See Also:

Constant Field Values

DEFAULT_SERVER_LIST_KEY

public static final String DEFAULT_SERVER_LIST_KEY

key to obtain the default server list via Settings.getProperty(String)

See Also:

Constant Field Values

DEFAULT_PORT

public static final int DEFAULT_PORT

123

See Also:

Constant Field Values

TIME_OFFSET

public static final double TIME_OFFSET

seconds between Jan-01-1990 and Jan-01-1970

See Also:

Constant Field Values

Constructor Detail

NTPClient

public NTPClient()

NTPClient

public NTPClient(String serverName)

NTPClient

public NTPClient(String serverName,
                 int port)

Method Detail

getServer

public String getServer()

setServer

public void setServer(String serverName)

getPort

public int getPort()

setPort

public void setPort(int port)

setTimeout

public void setTimeout(int timeout)

getTimeout

public int getTimeout()

aquireDelta

protected long aquireDelta()
                    throws IOException

Description copied from class: AbstractTimeSystem

returns the current difference between system time and the time of this implementation in milliseconds. A negative number indicates that the system clock is behind. Calling this method does not affect the delta value of this instance.

Specified by:

aquireDelta in class AbstractTimeSystem

Throws:

IOException

See Also:

AbstractTimeSystem.adjustDelta()

toString

public String toString()

Overrides:

toString in class Object

getDefaultServer

public static String getDefaultServer()

See Also:

DEFAULT_SERVER_KEY

setDefaultServer

public static void setDefaultServer(String server)

getDefaultServerList

public static String[] getDefaultServerList()

See Also:

DEFAULT_SERVER_LIST_KEY

setDefaultServerList

public static void setDefaultServerList(String... serverList)