org.radix.common.ID

Class EUID

java.lang.Object

org.radix.common.ID.EUID

All Implemented Interfaces:

java.lang.Comparable<EUID>

public final class EUID
extends java.lang.Object
implements java.lang.Comparable<EUID>

Field Summary

Fields

Modifier and Type	Field and Description
static int	BYTES Size in bytes.
static EUID	ONE
static EUID	TWO
static EUID	ZERO

Constructor Summary

Constructors

Constructor and Description
EUID(byte[] bytes) Constructor for creating an EUID from an array of bytes.
EUID(byte[] bytes, int offset) Constructor for creating an EUID from an array of bytes.
EUID(int value)
EUID(Int128 value)
EUID(long value)
EUID(java.lang.String s) Construct EUID from a String value.

Method Summary

Modifier and Type	Method and Description
int	compareDistances(EUID first, EUID second) Compare the distances of first and second from this, treating our unsigned 128-bit number system as a ring with values 0 and 2128-1 adjacent.
int	compareTo(EUID euid)
boolean	equals(java.lang.Object o)
long	getLow() Retrieve the lower 64-bit word of this EUID.
long	getShard() Retrieve the shard number of this EUID.
int	hashCode()
int	routingDistanceFrom(EUID other) Calculate the routing difference between this EUID and the specified EUID.
byte[]	toByteArray()
byte[]	toByteArray(byte[] bytes, int offset)
java.lang.String	toHexString()
java.lang.String	toString()
static EUID	valueOf(java.lang.String string)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

ZERO

public static final EUID ZERO

ONE

public static final EUID ONE

TWO

public static final EUID TWO

BYTES

public static final int BYTES

Size in bytes.

See Also:

Constant Field Values

Constructor Detail

EUID

public EUID(java.lang.String s)

Construct EUID from a String value. Hex conversion is performed.

Parameters:

s - The string to convert to an EUID.

Throws:

java.lang.IllegalArgumentException - If s does not contain a valid EUID.

EUID

public EUID(int value)

EUID

public EUID(long value)

EUID

public EUID(Int128 value)

EUID

public EUID(byte[] bytes)

Constructor for creating an EUID from an array of bytes. The array is most-significant byte first, and must not be zero length.

If the array is smaller than BYTES, then it is effectively padded with leading bytes with the correct sign.

If the array is longer than BYTES, then values at index BYTES and beyond are ignored.

Parameters:

bytes - The array of bytes to be used.

Throws:

java.lang.IllegalArgumentException - if bytes is 0 bytes in length.

See Also:

toByteArray()

EUID

public EUID(byte[] bytes,
            int offset)

Constructor for creating an EUID from an array of bytes. The array is most-significant byte first.

Parameters:

bytes - The array of bytes to be used.

offset - The offset of the bytes to be used.

See Also:

toByteArray()

Method Detail

valueOf

public static EUID valueOf(java.lang.String string)

getShard

public long getShard()

Retrieve the shard number of this EUID.

Returns:

The shard number of this EUID.

getLow

public long getLow()

Retrieve the lower 64-bit word of this EUID.

Returns:

The lower 64-bit word of this EUID.

routingDistanceFrom

public int routingDistanceFrom(EUID other)

Calculate the routing difference between this EUID and the specified EUID.

Currently the algorithm is numberOfLeadingZeros(this ^ other).

Parameters:

other - The EUID for which to calculate the routing distance from.

Returns:

The routing distance.

compareDistances

public int compareDistances(EUID first,
                            EUID second)

Compare the distances of first and second from this, treating our unsigned 128-bit number system as a ring with values 0 and 2¹²⁸-1 adjacent.

The algorithm for calculating distance between two nodes is:

distance = min_unsigned((a - b) mod 2¹²⁸, (b - a) mod 2¹²⁸)

Parameters:

first - The first ID to calculate distance

second - The second ID to calculate the distance

Returns:

0 if both distances are equal, 1 if first is further away and -1 if first is closer.

toByteArray

public byte[] toByteArray()

toByteArray

public byte[] toByteArray(byte[] bytes,
                          int offset)

compareTo

public int compareTo(EUID euid)

Specified by:

compareTo in interface java.lang.Comparable<EUID>

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toHexString

public java.lang.String toHexString()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object