package org.apache.commons.net.ntp;
/*
* Copyright 2001-2005 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/***
* Common NtpUtils Helper class.
*
* @author Jason Mathews, MITRE Corp
*
* @version $Revision: 165675 $ $Date: 2005-05-02 15:09:55 -0500 (Mon, 02 May 2005) $
*/
public final class NtpUtils {
/***
* Returns 32-bit integer address to IPv4 address string "%d.%d.%d.%d" format.
*
* @param address the 32-bit address
* @return the raw IP address in a string format.
*/
public static String getHostAddress(int address)
{
return ((address >>> 24) & 0xFF) + "." +
((address >>> 16) & 0xFF) + "." +
((address >>> 8) & 0xFF) + "." +
((address >>> 0) & 0xFF);
}
/***
* Returns NTP packet reference identifier as IP address.
*
* @param packet NTP packet
* @return the packet reference id (as IP address) in "%d.%d.%d.%d" format.
*/
public static String getRefAddress(NtpV3Packet packet)
{
int address = (packet == null) ? 0 : packet.getReferenceId();
return getHostAddress(address);
}
/***
* Get refId as reference clock string (e.g. GPS, WWV, LCL). If string is
* invalid (non-ASCII character) then returns empty string "".
* For details refer to the <A HREF="http://www.eecis.udel.edu/~mills/ntp/html/refclock.html#list">Comprehensive
* List of Clock Drivers</A>.
*
* @param message
* @return reference clock string if primary NTP server
*/
public static String getReferenceClock(NtpV3Packet message) {
if (message == null)
return "";
int refId = message.getReferenceId();
if (refId == 0)
return "";
StringBuffer buf = new StringBuffer(4);
// start at highest-order byte (0x4c434c00 -> LCL)
for (int shiftBits = 24; shiftBits >= 0; shiftBits -= 8)
{
char c = (char) ((refId >>> shiftBits) & 0xff);
if (c == 0) break; // 0-terminated ASCII string
if (!Character.isLetterOrDigit(c))
return "";
buf.append(c);
}
return buf.toString();
}
/***
* Return human-readable name of message mode type (RFC 1305).
*
* @param mode
* @return mode name
*/
public static String getModeName(int mode)
{
switch (mode) {
case NtpV3Packet.MODE_RESERVED:
return "Reserved";
case NtpV3Packet.MODE_SYMMETRIC_ACTIVE:
return "Symmetric Active";
case NtpV3Packet.MODE_SYMMETRIC_PASSIVE:
return "Symmetric Passive";
case NtpV3Packet.MODE_CLIENT:
return "Client";
case NtpV3Packet.MODE_SERVER:
return "Server";
case NtpV3Packet.MODE_BROADCAST:
return "Broadcast";
case NtpV3Packet.MODE_CONTROL_MESSAGE:
return "Control";
case NtpV3Packet.MODE_PRIVATE:
return "Private";
default:
return "Unknown";
}
}
}
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