org.apache.isis.core.metamodel.adapter.version

Class Version

java.lang.Object

org.apache.isis.core.metamodel.adapter.version.Version

All Implemented Interfaces:

Serializable, Encodable

public class Version
extends Object
implements Serializable, Encodable

An instance of this class is held by each ObjectAdapter and is used to represent a particular version (at a point in time) of domain object wrapped by that adapter.

This is normally done using some form of incrementing number or timestamp, which would be held within the implementing class. The numbers, timestamps, etc should change for each changed object, and the different() method should indicate that the two Version objects are different.

The user's name and a timestamp should alos be kept so that when an message is passed to the user it can be of the form "user has change object at time"

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Version(DataInputExtended input)

Method Summary

Methods

Modifier and Type	Method and Description
static Version	create(Long sequence)
static Version	create(Long sequence, String user, Date time)
static Version	create(Long sequence, String user, Long utcTimestamp)
static Version	create(String sequence, String user, String utcTimestamp)
boolean	different(Version version) Compares this version against the specified version and returns true if they are different versions (by checking getSequence()).
void	encode(DataOutputExtended output) Returns the domain object's value as an encoded byte array via the encoder.
String	enString(OidMarshaller oidMarshaller)
boolean	equals(Object obj)
long	getSequence() The internal, strictly monotonically increasing, version number.
Date	getTime() Returns the time of the last change (used for display/reporting only, not comparison)
String	getUser() Returns the user who made the last change (used for display/reporting only)
Long	getUtcTimestamp() The time of the last change, as UTC milliseconds.
int	hashCode()
String	sequence() Returns the sequence for printing/display
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Version

public Version(DataInputExtended input)
        throws IOException

Throws:

IOException

Method Detail

create

public static Version create(Long sequence)

create

public static Version create(String sequence,
             String user,
             String utcTimestamp)

create

public static Version create(Long sequence,
             String user,
             Date time)

create

public static Version create(Long sequence,
             String user,
             Long utcTimestamp)

encode

public void encode(DataOutputExtended output)
            throws IOException

Description copied from interface: Encodable

Returns the domain object's value as an encoded byte array via the encoder.

Specified by:

encode in interface Encodable

Throws:

IOException

getSequence

public long getSequence()

The internal, strictly monotonically increasing, version number.

This might be the timestamp of the change, or it might be simply a number incrementing 1,2,3...

getUser

public String getUser()

Returns the user who made the last change (used for display/reporting only)

May be null.

getUtcTimestamp

public Long getUtcTimestamp()

The time of the last change, as UTC milliseconds.

May be null.

See Also:

getTime()

getTime

public Date getTime()

Returns the time of the last change (used for display/reporting only, not comparison)

May be null.

See Also:

getUtcTimestamp()

enString

public String enString(OidMarshaller oidMarshaller)

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

different

public boolean different(Version version)

Compares this version against the specified version and returns true if they are different versions (by checking getSequence()).

This is use for optimistic checking, where the existence of a different version will normally cause a concurrency exception.

toString

public String toString()

Overrides:

toString in class Object

sequence

public String sequence()

Returns the sequence for printing/display