org.opends.server.replication.common

Class CSN

java.lang.Object

org.opends.server.replication.common.CSN

All Implemented Interfaces:

Serializable, Comparable<CSN>

public class CSN
extends Object
implements Serializable, Comparable<CSN>

Class used to represent Change Sequence Numbers.

See Also:

Inspiration for this class comes from LDAPChangeSequenceNumber, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CSN.CsnVersion The version of a CSN to ask for a particular representation.

Field Summary

Fields

Modifier and Type	Field and Description
static int	BYTE_ENCODING_V1_LENGTH The number of bytes used by the byte string representation of a change number v0.
static CSN	MIN_VALUE The minimum possible value for a CSN.
static int	REPLICA_NAME_POSITION The position of the replica name in a string representation of a CSN.
static int	STRING_ENCODING_V1_LENGTH The number of characters used by the string representation of a change number v0.

Constructor Summary

Constructors

Constructor and Description
CSN(long timeStamp, int seqNum, int replicaId) Create a new CSN.
CSN(long timeStamp, int seqNum, ReplicaId replicaId) Create a new CSN.

Method Summary

Modifier and Type	Method and Description
static int	compare(CSN csn1, CSN csn2) Compares this CSN with the provided CSN for order and returns a negative number if csn1 is older than csn2, zero if they have the same age, or a positive number if csn1 is newer than csn2.
int	compareTo(CSN csn) Compares this CSN with the provided CSN for order and returns a negative number if this CSN is older than csn, zero if they have the same age, or a positive number if this CSN is newer than csn.
static int	diffSeqNum(CSN csn1, CSN csn2) Computes the difference in number of changes between 2 CSNs.
boolean	equals(Object obj)
ReplicaId	getReplicaId() Getter for the replica ID.
int	getSeqnum() Getter for the sequence number.
long	getTime() Getter for the time.
long	getTimeSec() Get the timestamp associated to this CSN in seconds.
int	hashCode()
boolean	isNewerThan(CSN csn) Returns true if this CSN is newer than the provided CSN.
boolean	isNewerThanOrEqualTo(CSN csn) Returns true if this CSN is newer than or equal to the provided CSN.
boolean	isOlderThan(CSN csn) Returns true if this CSN is older than the provided CSN.
boolean	isOlderThanOrEqualTo(CSN csn) Returns true if this CSN is older than or equal to the provided CSN.
static CSN	newestCsn(long timeStamp) Return the newest possible CSN for the given time.
static CSN	newestCsn(ReplicaId replicaId) Returns the newest possible CSN for a replica.
static CSN	oldestCsn(long timeStamp) Returns the oldest possible CSN for the given time.
static CSN	oldestCsn(ReplicaId replicaId) Returns the oldest possible CSN for a replica.
static void	skipCsn(ByteSequenceReader reader) Advances reading the provided reader to the end of the CSN representation, by skipping over it.
ByteString	toByteString() Encodes this CSN as a byte string.
void	toByteString(ByteStringBuilder builder) Encodes this CSN into the provided byte string builder.
void	toByteString(ByteStringBuilder builder, CSN.CsnVersion version) Encodes this CSN into the provided byte string builder according to the given CSN version.
ByteString	toByteString(CSN.CsnVersion version) Encodes this CSN as a byte string according to the given CSN version.
String	toString() Convert the CSN to a printable String.
String	toString(CSN.CsnVersion version) Convert the CSN to a printable String according to the given CSN version.
String	toStringUI() Convert the CSN to a printable String with a user friendly format.
static CSN	valueOf(ByteSequence bs) Decodes the provided toByteString(CsnVersion) representation of a CSN.
static CSN	valueOf(ByteSequenceReader reader) Decodes the provided toByteString(CsnVersion) representation of a CSN, possibly embedded in a larger sequence.
static CSN	valueOf(String str) Parses the provided toString() representation of a CSN.

Methods inherited from class java.lang.Object

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

Field Detail

BYTE_ENCODING_V1_LENGTH

public static final int BYTE_ENCODING_V1_LENGTH

The number of bytes used by the byte string representation of a change number v0.

See Also:

valueOf(ByteSequence), toByteString(CsnVersion), toByteString(ByteStringBuilder, CsnVersion), Constant Field Values

STRING_ENCODING_V1_LENGTH

public static final int STRING_ENCODING_V1_LENGTH

The number of characters used by the string representation of a change number v0.

See Also:

valueOf(String), toString(), Constant Field Values

MIN_VALUE

public static final CSN MIN_VALUE

The minimum possible value for a CSN.

REPLICA_NAME_POSITION

public static final int REPLICA_NAME_POSITION

The position of the replica name in a string representation of a CSN.

See Also:

Constant Field Values

Constructor Detail

CSN

public CSN(long timeStamp,
           int seqNum,
           int replicaId)

Create a new CSN.

Parameters:

timeStamp - timeStamp for the CSN

seqNum - sequence number

replicaId - identity of replica

CSN

public CSN(long timeStamp,
           int seqNum,
           ReplicaId replicaId)

Create a new CSN.

Parameters:

timeStamp - timeStamp for the CSN

seqNum - sequence number

replicaId - identity of replica

Method Detail

valueOf

public static CSN valueOf(String str)

Parses the provided toString() representation of a CSN.

Parameters:

str - The string to be parsed.

Returns:

The parsed CSN.

See Also:

toString()

valueOf

public static CSN valueOf(ByteSequence bs)

Decodes the provided toByteString(CsnVersion) representation of a CSN.

Parameters:

bs - The byte sequence to be parsed.

Returns:

The decoded CSN.

See Also:

toByteString(CsnVersion)

skipCsn

public static void skipCsn(ByteSequenceReader reader)

Advances reading the provided reader to the end of the CSN representation, by skipping over it.

Parameters:

reader - The reader to advance

valueOf

public static CSN valueOf(ByteSequenceReader reader)

Decodes the provided toByteString(CsnVersion) representation of a CSN, possibly embedded in a larger sequence.

Parameters:

reader - The reader of the byte sequence to be parsed.

Returns:

The decoded CSN.

getTime

public long getTime()

Getter for the time.

Returns:

the time

getTimeSec

public long getTimeSec()

Get the timestamp associated to this CSN in seconds.

Returns:

timestamp associated to this CSN in seconds

getSeqnum

public int getSeqnum()

Getter for the sequence number.

Returns:

the sequence number

getReplicaId

public ReplicaId getReplicaId()

Getter for the replica ID.

Returns:

the replica ID

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toByteString

public ByteString toByteString()

Encodes this CSN as a byte string.

The returned representation is according to the most recent CSN version. Use toByteString(CsnVersion) to get a representation compatible with earlier protocol versions.

Returns:

The encoded representation of this CSN.

See Also:

valueOf(ByteSequence)

toByteString

public void toByteString(ByteStringBuilder builder)

Encodes this CSN into the provided byte string builder.

The returned representation is according to the most recent CSN version. Use toByteString(ByteStringBuilder, CsnVersion) to get a representation compatible with earlier protocol versions.

Parameters:

builder - The byte string builder.

See Also:

valueOf(ByteSequence)

toByteString

public ByteString toByteString(CSN.CsnVersion version)

Encodes this CSN as a byte string according to the given CSN version.

Parameters:

version - The required representation version

Returns:

The encoded representation of this CSN.

toByteString

public void toByteString(ByteStringBuilder builder,
                         CSN.CsnVersion version)

Encodes this CSN into the provided byte string builder according to the given CSN version.

Parameters:

builder - The byte string builder.

version - The required representation version

See Also:

valueOf(ByteSequence)

toString

public String toString()

Convert the CSN to a printable String.

The returned representation is according to the most recent CSN version. Use toString(CsnVersion) to get a representation compatible with earlier protocol versions.

Overrides:

toString in class Object

Returns:

the string

toString

public String toString(CSN.CsnVersion version)

Convert the CSN to a printable String according to the given CSN version.

Parameters:

version - The required representation version

Returns:

the string

toStringUI

public String toStringUI()

Convert the CSN to a printable String with a user friendly format.

Returns:

the string

compare

public static int compare(CSN csn1,
                          CSN csn2)

Compares this CSN with the provided CSN for order and returns a negative number if csn1 is older than csn2, zero if they have the same age, or a positive number if csn1 is newer than csn2.

Parameters:

csn1 - The first CSN to be compared, which may be null.

csn2 - The second CSN to be compared, which may be null.

Returns:

A negative number if csn1 is older than csn2, zero if they have the same age, or a positive number if csn1 is newer than csn2.

diffSeqNum

public static int diffSeqNum(CSN csn1,
                             CSN csn2)

Computes the difference in number of changes between 2 CSNs. First one is expected to be newer than second one. If this is not the case, 0 will be returned.

Parameters:

csn1 - the first CSN

csn2 - the second CSN

Returns:

the difference

isOlderThan

public boolean isOlderThan(CSN csn)

Returns true if this CSN is older than the provided CSN.

Parameters:

csn - The CSN to be compared.

Returns:

true if this CSN is older than the provided CSN.

isOlderThanOrEqualTo

public boolean isOlderThanOrEqualTo(CSN csn)

Returns true if this CSN is older than or equal to the provided CSN.

Parameters:

csn - The CSN to be compared.

Returns:

true if this CSN is older than or equal to the provided CSN.

isNewerThanOrEqualTo

public boolean isNewerThanOrEqualTo(CSN csn)

Returns true if this CSN is newer than or equal to the provided CSN.

Parameters:

csn - The CSN to be compared.

Returns:

true if this CSN is newer than or equal to the provided CSN.

isNewerThan

public boolean isNewerThan(CSN csn)

Returns true if this CSN is newer than the provided CSN.

Parameters:

csn - The CSN to be compared.

Returns:

true if this CSN is newer than the provided CSN.

compareTo

public int compareTo(CSN csn)

Compares this CSN with the provided CSN for order and returns a negative number if this CSN is older than csn, zero if they have the same age, or a positive number if this CSN is newer than csn.

Specified by:

compareTo in interface Comparable<CSN>

Parameters:

csn - The CSN to be compared.

Returns:

A negative number if this CSN is older than csn, zero if they have the same age, or a positive number if this CSN is newer than csn.

oldestCsn

public static CSN oldestCsn(long timeStamp)

Returns the oldest possible CSN for the given time.

Parameters:

timeStamp - the time of the CSN

Returns:

the oldest possible CSN for the given time

oldestCsn

public static CSN oldestCsn(ReplicaId replicaId)

Returns the oldest possible CSN for a replica.

Parameters:

replicaId - the replica

Returns:

the oldest possible CSN for a replica

newestCsn

public static CSN newestCsn(long timeStamp)

Return the newest possible CSN for the given time.

Parameters:

timeStamp - the time of the CSN

Returns:

the newest possible CSN for the given time

newestCsn

public static CSN newestCsn(ReplicaId replicaId)

Returns the newest possible CSN for a replica.

Parameters:

replicaId - the replica

Returns:

the newest possible CSN for a replica