Package org.apache.commons.net.ntp

Class NtpV3Impl

  • All Implemented Interfaces:
    NtpV3Packet
    public class NtpV3Impl
extends java.lang.Object
implements NtpV3Packet
    Implements NtpV3Packet to convert Java objects to and from the Network Time Protocol (NTP) data message header format described in RFC-1305.

    • Constructor Detail

      • NtpV3Impl

        public NtpV3Impl()
        Creates a new instance of NtpV3Impl

    • Method Detail

      • ui

        protected static final int ui​(byte b)
        Convert byte to unsigned integer. Java only has signed types, so we have to do more work to get unsigned ops.
        Parameters:
        b - input byte
        Returns:
        unsigned int value of byte

      • ul

        protected static final long ul​(byte b)
        Convert byte to unsigned long. Java only has signed types, so we have to do more work to get unsigned ops
        Parameters:
        b - input byte
        Returns:
        unsigned long value of byte

      • equals

        public boolean equals​(java.lang.Object obj)
        Compares this object against the specified object. The result is true if and only if the argument is not null and is a NtpV3Impl object that contains the same values as this object.
        Overrides:
        equals in class java.lang.Object
        Parameters:
        obj - the object to compare with.
        Returns:
        true if the objects are the same; false otherwise.
        Since:
        3.4

      • getDatagramPacket

        public java.net.DatagramPacket getDatagramPacket()
        Gets the datagram packet with the NTP details already filled in.
        Specified by:
        getDatagramPacket in interface NtpV3Packet
        Returns:
        a datagram packet.

      • getInt

        private int getInt​(int index)
        Gets 4 bytes as 32-bit int.
        Returns:
        4 bytes as 32-bit int

      • getLeapIndicator

        public int getLeapIndicator()
        Gets leap indicator as defined in RFC-1305 which is a two-bit code: 0=no warning 1=last minute has 61 seconds 2=last minute has 59 seconds 3=alarm condition (clock not synchronized)
        Specified by:
        getLeapIndicator in interface NtpV3Packet
        Returns:
        leap indicator as defined in RFC-1305.

      • getLong

        private long getLong​(int index)
        Gets Long value represented by bits starting at specified index.
        Returns:
        8 bytes as 64-bit long

      • getMode

        public int getMode()
        Gets the mode as defined in RFC-1305 which is a 3-bit integer whose value is indicated by the MODE_xxx parameters.
        Specified by:
        getMode in interface NtpV3Packet
        Returns:
        mode as defined in RFC-1305.

      • getModeName

        public java.lang.String getModeName()
        Gets the human-readable name of message mode type as described in RFC 1305.
        Specified by:
        getModeName in interface NtpV3Packet
        Returns:
        mode name as string.

      • getOriginateTimeStamp

        public TimeStamp getOriginateTimeStamp()
        Gets the originate time as defined in RFC-1305.
        Specified by:
        getOriginateTimeStamp in interface NtpV3Packet
        Returns:
        the originate time. Never returns null.

      • getPoll

        public int getPoll()
        Gets the poll interval as defined in RFC-1305, which is an eight-bit signed integer indicating the maximum interval between successive messages, in seconds to the nearest power of two (e.g. value of six indicates an interval of 64 seconds). The values that can appear in this field range from NTP_MINPOLL to NTP_MAXPOLL inclusive.
        Specified by:
        getPoll in interface NtpV3Packet
        Returns:
        poll interval as defined in RFC-1305.

      • getPrecision

        public int getPrecision()
        Gets the precision as defined in RFC-1305 encoded as an 8-bit signed integer (seconds to the nearest power of two). Values normally range from -6 to -20.
        Specified by:
        getPrecision in interface NtpV3Packet
        Returns:
        precision as defined in RFC-1305.

      • getReceiveTimeStamp

        public TimeStamp getReceiveTimeStamp()
        Gets the receive timestamp as defined in RFC-1305.
        Specified by:
        getReceiveTimeStamp in interface NtpV3Packet
        Returns:
        the receive time. Never returns null.

      • getReferenceId

        public int getReferenceId()
        Gets the reference id as defined in RFC-1305, which is a 32-bit integer whose value is dependent on several criteria.
        Specified by:
        getReferenceId in interface NtpV3Packet
        Returns:
        the reference id as defined in RFC-1305.

      • getReferenceIdString

        public java.lang.String getReferenceIdString()
        Gets the reference id string. String cannot be null but value is dependent on the version of the NTP spec supported and stratum level. Value can be an empty string, clock type string, IP address, or a hexadecimal string.
        Specified by:
        getReferenceIdString in interface NtpV3Packet
        Returns:
        the reference id string.

      • getReferenceTimeStamp

        public TimeStamp getReferenceTimeStamp()
        Gets the reference time as defined in RFC-1305.
        Specified by:
        getReferenceTimeStamp in interface NtpV3Packet
        Returns:
        the reference time as TimeStamp object. Never returns null.

      • getRootDelay

        public int getRootDelay()
        Gets the root delay as defined in RFC-1305, which is the total roundtrip delay to the primary reference source, in seconds. Values can take positive and negative values, depending on clock precision and skew.
        Specified by:
        getRootDelay in interface NtpV3Packet
        Returns:
        root delay as defined in RFC-1305.

      • getRootDelayInMillisDouble

        public double getRootDelayInMillisDouble()
        Gets the root delay as defined in RFC-1305 in milliseconds, which is the total roundtrip delay to the primary reference source, in seconds. Values can take positive and negative values, depending on clock precision and skew.
        Specified by:
        getRootDelayInMillisDouble in interface NtpV3Packet
        Returns:
        root delay in milliseconds

      • getRootDispersion

        public int getRootDispersion()
        Gets the root dispersion as defined in RFC-1305.
        Specified by:
        getRootDispersion in interface NtpV3Packet
        Returns:
        root dispersion.

      • getRootDispersionInMillis

        public long getRootDispersionInMillis()
        Gets the root dispersion (as defined in RFC-1305) in milliseconds.
        Specified by:
        getRootDispersionInMillis in interface NtpV3Packet
        Returns:
        root dispersion in milliseconds

      • getRootDispersionInMillisDouble

        public double getRootDispersionInMillisDouble()
        Gets the root dispersion (as defined in RFC-1305) in milliseconds as double precision value.
        Specified by:
        getRootDispersionInMillisDouble in interface NtpV3Packet
        Returns:
        root dispersion in milliseconds

      • getStratum

        public int getStratum()
        Gets the Stratum as defined in RFC-1305, which indicates the stratum level of the local clock, with values defined as follows: 0=unspecified, 1=primary ref clock, and all others a secondary reference (via NTP).
        Specified by:
        getStratum in interface NtpV3Packet
        Returns:
        Stratum level as defined in RFC-1305.

      • getTimestamp

        private TimeStamp getTimestamp​(int index)
        Gets the NTP Timestamp at specified starting index.
        Parameters:
        index - index into data array
        Returns:
        TimeStamp object for 64 bits starting at index

      • getTransmitTimeStamp

        public TimeStamp getTransmitTimeStamp()
        Gets the transmit timestamp as defined in RFC-1305.
        Specified by:
        getTransmitTimeStamp in interface NtpV3Packet
        Returns:
        the transmit timestamp as defined in RFC-1305. Never returns a null object.

      • getType

        public java.lang.String getType()
        Gets the type of time packet. The values (e.g. NTP, TIME, ICMP, ...) correspond to the protocol used to obtain the timing information.
        Specified by:
        getType in interface NtpV3Packet
        Returns:
        packet type string identifier which in this case is "NTP".

      • getVersion

        public int getVersion()
        Gets the NTP version number as defined in RFC-1305.
        Specified by:
        getVersion in interface NtpV3Packet
        Returns:
        NTP version number.

      • hashCode

        public int hashCode()
        Computes a hash code for this object. The result is the exclusive OR of the values of this object stored as a byte array.
        Overrides:
        hashCode in class java.lang.Object
        Returns:
        a hash code value for this object.
        Since:
        3.4

      • idAsHex

        private java.lang.String idAsHex()

      • idAsIPAddress

        private java.lang.String idAsIPAddress()
        Returns Reference id as dotted IP address.
        Returns:
        refId as IP address string.

      • idAsString

        private java.lang.String idAsString()

      • setDatagramPacket

        public void setDatagramPacket​(java.net.DatagramPacket srcDp)
        Sets the contents of this object from source datagram packet.
        Specified by:
        setDatagramPacket in interface NtpV3Packet
        Parameters:
        srcDp - source DatagramPacket to copy contents from, never null.
        Throws:
        java.lang.IllegalArgumentException - if srcDp is null or byte length is less than minimum length of 48 bytes

      • setInt

        private void setInt​(int idx,
                    int value)
        Sets integer value at index position.
        Parameters:
        idx - index position
        value - 32-bit int value

      • setLeapIndicator

        public void setLeapIndicator​(int li)
        Sets leap indicator as defined in RFC-1305.
        Specified by:
        setLeapIndicator in interface NtpV3Packet
        Parameters:
        li - leap indicator.

      • setMode

        public void setMode​(int mode)
        Sets mode as defined in RFC-1305.
        Specified by:
        setMode in interface NtpV3Packet
        Parameters:
        mode - the mode to set

      • setOriginateTimeStamp

        public void setOriginateTimeStamp​(TimeStamp ts)
        Sets originate timestamp given NTP TimeStamp object. If ts is null then zero time is used.
        Specified by:
        setOriginateTimeStamp in interface NtpV3Packet
        Parameters:
        ts - NTP timestamp

      • setPoll

        public void setPoll​(int poll)
        Sets poll interval as defined in RFC-1305.
        Specified by:
        setPoll in interface NtpV3Packet
        Parameters:
        poll - poll interval.

      • setPrecision

        public void setPrecision​(int precision)
        Sets precision as defined in RFC-1305.
        Specified by:
        setPrecision in interface NtpV3Packet
        Parameters:
        precision - the precision to set
        Since:
        3.4

      • setReceiveTimeStamp

        public void setReceiveTimeStamp​(TimeStamp ts)
        Sets receive timestamp given NTP TimeStamp object. If ts is null then zero time is used.
        Specified by:
        setReceiveTimeStamp in interface NtpV3Packet
        Parameters:
        ts - timestamp

      • setReferenceId

        public void setReferenceId​(int refId)
        Sets reference clock identifier field with 32-bit unsigned integer value. See RFC-1305 for description.
        Specified by:
        setReferenceId in interface NtpV3Packet
        Parameters:
        refId - reference clock identifier.

      • setReferenceTime

        public void setReferenceTime​(TimeStamp ts)
        Sets Reference time with NTP timestamp. If ts is null then zero time is used.
        Specified by:
        setReferenceTime in interface NtpV3Packet
        Parameters:
        ts - NTP timestamp

      • setRootDelay

        public void setRootDelay​(int delay)
        Sets root delay as defined in RFC-1305.
        Specified by:
        setRootDelay in interface NtpV3Packet
        Parameters:
        delay - root delay
        Since:
        3.4

      • setRootDispersion

        public void setRootDispersion​(int dispersion)
        Sets root dispersion as defined in RFC-1305.
        Specified by:
        setRootDispersion in interface NtpV3Packet
        Parameters:
        dispersion - root dispersion
        Since:
        3.4

      • setStratum

        public void setStratum​(int stratum)
        Sets stratum level as defined in RFC-1305.
        Specified by:
        setStratum in interface NtpV3Packet
        Parameters:
        stratum - stratum level.

      • setTimestamp

        private void setTimestamp​(int index,
                          TimeStamp t)
        Sets the NTP timestamp at the given array index.
        Parameters:
        index - index into the byte array.
        t - TimeStamp.

      • setTransmitTime

        public void setTransmitTime​(TimeStamp ts)
        Sets transmit time with NTP timestamp. If ts is null then zero time is used.
        Specified by:
        setTransmitTime in interface NtpV3Packet
        Parameters:
        ts - NTP timestamp

      • setVersion

        public void setVersion​(int version)
        Sets NTP version as defined in RFC-1305.
        Specified by:
        setVersion in interface NtpV3Packet
        Parameters:
        version - NTP version.

      • toString

        public java.lang.String toString()
        Returns details of NTP packet as a string.
        Overrides:
        toString in class java.lang.Object
        Returns:
        details of NTP packet as a string.