wt.eff
Class UpdateEffsTask

java.lang.Object
  wt.eff.UpdateEffsTask

class UpdateEffsTask

extends Object

This class encapsulates the logic for updating the effectivity vector of one or more EffManagedVersion objects, recording the history of effectivity changes as appropriate.

Field Summary

private EffChangeAudit	audit
private ChangeActivityIfc	authorizedBy
private static EffSet	EMPTY_SET
private HashMap	emvMap
private WTHashSet	modifiedVersions
private static Boolean	recordHistory
private static String	RESOURCE

Constructor Summary

UpdateEffsTask(EffManagedVersion[] emvs, ChangeActivityIfc authorizedBy)
Constructs a new UpdateEffsTask object for a particular batch of effectivity updates.

Method Summary

private void	advanceCreation(EffSet effSet) Advances the creation audits of the specified Eff objects.
private void	advanceDeletion(EffSet effSet) Advances the factual deletion audits of the specified Eff objects.
private void	delete(EffSet effSet) Factually deletes specified Eff objects.
private EffSet	difference(EffSet a, EffSet b)
private EffChangeAudit	getAudit() Returns a previously cached EffChangeAudit object, or a new one if none has been previously cached.
private static boolean	historyExists() Returns true if and only if any effectivity history has been recorded in the system.
private EffSet	intersection(EffSet a, EffSet b)
private static boolean	isRecordHistory() Returns true if and only if history should be recorded in general.
private boolean	isRecordHistory(EffManagedVersion emv, int hSize, int phSize) Returns true if and only if effectivity history should be recorded for the specified EffManagedVersion object.
private void	remove(EffSet effSet) Properly deletes (i.e., removes from persistence) the specified Eff objects.
private void	restore(EffSet effSet) Restores from factual deletion the specified Eff objects.
private void	store(EffSet effSet) Persist the specified new Eff objects.
private EffSet	union(EffSet a, EffSet b)
void	updateEffs(long emvBID, EffSet newEffs, EffHistoryMap antiHistoryMap, int predHistSize) Updates the effectivities of the specified EffManagedVersion.
void	updateVersions() Nominally updates (i.e.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

RESOURCE

private static final String RESOURCE

See Also:

Constant Field Values

EMPTY_SET

private static final EffSet EMPTY_SET

recordHistory

private static Boolean recordHistory

emvMap

private HashMap emvMap

authorizedBy

private ChangeActivityIfc authorizedBy

audit

private EffChangeAudit audit

modifiedVersions

private WTHashSet modifiedVersions

Constructor Detail

UpdateEffsTask

public UpdateEffsTask(EffManagedVersion[] emvs,
                      ChangeActivityIfc authorizedBy)

Constructs a new UpdateEffsTask object for a particular batch of effectivity updates.

Parameters:

emvs - array of EffManagedVersions whose effectivity vectors will possibly be updated by this UpdateEffsTask authorizedBy change activity object via which the effectivity update is being performed (for audit purposes); may be null

Method Detail

updateEffs

public void updateEffs(long emvBID,
                       EffSet newEffs,
                       EffHistoryMap antiHistoryMap,
                       int predHistSize)
                throws WTPropertyVetoException,
                       WTException

Updates the effectivities of the specified EffManagedVersion.

Parameters:

emvBID - branch identifier of the EffManagedVersion whose effectivity is being updated newEffs Set of Eff objects defining the new (cumulative) effectivity value for an implicitly given EffContext and Eff type antiHistoryMap EffHistoryMap of the effectivity history for the specified EffManagedVersion for the same implicitly given EffContext and Eff type, in anti-chronological order (i.e. the first element of the map represents the current effectivity) predHistSize the cardinality of the specified EffManagedVersion's predecessor's effectivity history (or zero if no such history exists) for the same implicitly given EffContext and Eff type

Throws:

WTPropertyVetoException

WTException

updateVersions

public void updateVersions()
                    throws WTException

Nominally updates (i.e. updates the update count of) EffManagedVersion objects whose effectivities have been updated by this UpdateEffsTask.

Throws:

WTException

isRecordHistory

private boolean isRecordHistory(EffManagedVersion emv,
                                int hSize,
                                int phSize)
                         throws WTException,
                                WTPropertyVetoException

Returns true if and only if effectivity history should be recorded for the specified EffManagedVersion object. This depends upon whether effectivity history is generally recorded, whether the version is private, and if so, on the relative sizes of the version's effectivity history and its predecessor's.

Parameters:

emv - EffManagedVersion for which effectivity history recording is to be determined hSize the size of the argument EffManagedVersion's effectivity history for an implicitly given EffContext and Eff type phSize the size of the argument EffManagedVersion's predecessor version's effectivity history for the same implicitly given EffContext and Eff type

Throws:

WTException

WTPropertyVetoException

isRecordHistory

private static boolean isRecordHistory()
                                throws WTException,
                                       WTPropertyVetoException

Returns true if and only if history should be recorded in general. This depends on the value of the wt.eff.recordHistory property setting. If this setting is false, but history has already been recorded, then a WTException is thrown.

Returns:

true if and only if history should be recorded in general

Throws:

WTException

WTPropertyVetoException

historyExists

private static boolean historyExists()
                              throws WTException

Returns true if and only if any effectivity history has been recorded in the system. This is the case if either of the following conditions is met: (1) at least one persistent Eff object has a valid deletion reference, or (2) at least one group of relevant Eff objects (i.e. those Eff objects of the same type associated with the same version and context, if any) has at least two members with differing valid creation references.

Returns:

true if and only if any effetivity history has been recorded in the system

Throws:

WTException

union

private EffSet union(EffSet a,
                     EffSet b)

intersection

private EffSet intersection(EffSet a,
                            EffSet b)

difference

private EffSet difference(EffSet a,
                          EffSet b)

restore

private void restore(EffSet effSet)
              throws WTPropertyVetoException,
                     WTException

Restores from factual deletion the specified Eff objects. This is appropriate when an Eff value is 'recreated' immediately following its factual deletion and history recording has been suspended (say, for a modified working copy of an EffManagedVersion).

Parameters:

effSet - EffSet of Eff objects that have previously been factually deleted, that are to be restored

Throws:

WTPropertyVetoException

WTException

advanceCreation

private void advanceCreation(EffSet effSet)
                      throws WTPropertyVetoException,
                             WTException

Advances the creation audits of the specified Eff objects. This is appropriate when an Eff value is 'carried forward' immediately following its creation and the suspension of history recording (say, for a modified working copy of an EffManagedVersion).

Parameters:

effSet - EffSet of Eff objects whose creation is to be advanced

Throws:

WTPropertyVetoException

WTException

advanceDeletion

private void advanceDeletion(EffSet effSet)
                      throws WTPropertyVetoException,
                             WTException

Advances the factual deletion audits of the specified Eff objects. This is appropriate when a factually deleted Eff value is to remain so immediately following its factual deletion and the suspension of history recording (say, for a modified working copy of an EffManagedVersion).

Parameters:

effSet - EffSet of Eff objects whose factual deletion is to be advanced

Throws:

WTPropertyVetoException

WTException

delete

private void delete(EffSet effSet)
             throws WTPropertyVetoException,
                    WTException

Factually deletes specified Eff objects. This is appropriate when effectivity history is being recorded.

Parameters:

effSet - EffSet of Eff objects to be factually deleted

Throws:

WTPropertyVetoException

WTException

store

private void store(EffSet effSet)
            throws WTPropertyVetoException,
                   WTException

Persist the specified new Eff objects.

Parameters:

effSet - EffSet of new (non-persistent) Eff objects to be persisted

Throws:

WTPropertyVetoException

WTException

remove

private void remove(EffSet effSet)
             throws WTException

Properly deletes (i.e., removes from persistence) the specified Eff objects. This is appropriate when history recording has been suspended (say, for a modified working copy of an EffManagedVersion).

Parameters:

effSet - EffSet of existing (persistent) Eff objects to be properly deleted

Throws:

WTException

getAudit

private EffChangeAudit getAudit()
                         throws WTException,
                                WTPropertyVetoException

Returns a previously cached EffChangeAudit object, or a new one if none has been previously cached. The same EffChangeAudit object is meant to apply to all effectivity modifications effected by this UpdateEffsTask object, hence the caching.

Throws:

WTException

WTPropertyVetoException