org.apache.directory.server.core.changelog

Class DefaultChangeLog

java.lang.Object

org.apache.directory.server.core.changelog.DefaultChangeLog

All Implemented Interfaces:

ChangeLog

public class DefaultChangeLog
extends Object
implements ChangeLog

The default ChangeLog service implementation. It stores operations in memory. Entries are stored into a dedicated partition, named ou=changelog, under which we have two other sub-entries : ou=tags and ou= revisions : ou=changelog | +-- ou=revisions | +-- ou=tags

Author:

Apache Directory Project

Constructor Summary

Constructors

Constructor and Description
DefaultChangeLog()

Method Summary

Modifier and Type	Method and Description
void	destroy() Destroy the changeLog
ChangeLogSearchEngine	getChangeLogSearchEngine() Gets the change log query engine which would be used to ask questions about what changed, when, how and by whom.
ChangeLogStore	getChangeLogStore()
long	getCurrentRevision() Gets the current revision for the server.
Tag	getLatest()
TagSearchEngine	getTagSearchEngine() Gets the tag search engine used to query the snapshots taken.
void	init(DirectoryService service) Initialize the ChangeLog system.
boolean	isEnabled() Checks whether or not the change log has been enabled to track changes.
boolean	isExposed()
boolean	isLogSearchSupported() Returns whether or not this ChangeLogService supports searching for changes.
boolean	isTagSearchSupported() Returns whether or not this ChangeLogService supports searching for snapshot tags.
boolean	isTagStorageSupported() Returns whether or not this ChangeLogService stores snapshot tags.
ChangeLogEvent	log(LdapPrincipal principal, org.apache.directory.api.ldap.model.ldif.LdifEntry forward, org.apache.directory.api.ldap.model.ldif.LdifEntry reverse) Records a change as a forward LDIF, a reverse change to revert the change and the authorized principal triggering the revertable change event.
ChangeLogEvent	log(LdapPrincipal principal, org.apache.directory.api.ldap.model.ldif.LdifEntry forward, List<org.apache.directory.api.ldap.model.ldif.LdifEntry> reverses) Records a change as a forward LDIF, some reverse changes to revert the change and the authorized principal triggering the revertable change event.
void	setChangeLogStore(ChangeLogStore store) Set the underlying storage
void	setEnabled(boolean enabled) Enable or disable the ChangeLog service
void	setExposed(boolean exposed) Exposes the contents of ChangeLog to clients if set to true.
void	setPartitionSuffix(String suffix) The prefix of the partition.
void	setRevisionsContainerName(String revContainerName) The name of the revisions container under the partition.
void	setTagsContainerName(String tagContainerName) The name of the tags container under the partition.
void	sync() Flush the changes to disk
Tag	tag() Creates a snapshot of the server at the current revision.
Tag	tag(long revision) Creates a tag for a snapshot of the server in a specific state at a revision.
Tag	tag(long revision, String description) Creates a tag for a snapshot of the server in a specific state at a revision.
Tag	tag(String description) Creates a snapshot of the server at the current revision.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultChangeLog

public DefaultChangeLog()

Method Detail

getChangeLogStore

public ChangeLogStore getChangeLogStore()

Specified by:

getChangeLogStore in interface ChangeLog

Returns:

The underlying storage

setChangeLogStore

public void setChangeLogStore(ChangeLogStore store)

Set the underlying storage If there is an existing changeLog store, we don't switch it

Specified by:

setChangeLogStore in interface ChangeLog

Parameters:

store - The storage

getCurrentRevision

public long getCurrentRevision()
                        throws org.apache.directory.api.ldap.model.exception.LdapException

Gets the current revision for the server.

Specified by:

getCurrentRevision in interface ChangeLog

Returns:

the current revision

Throws:

org.apache.directory.api.ldap.model.exception.LdapException

log

public ChangeLogEvent log(LdapPrincipal principal,
                          org.apache.directory.api.ldap.model.ldif.LdifEntry forward,
                          org.apache.directory.api.ldap.model.ldif.LdifEntry reverse)
                   throws org.apache.directory.api.ldap.model.exception.LdapException

Records a change as a forward LDIF, a reverse change to revert the change and the authorized principal triggering the revertable change event.

Specified by:

log in interface ChangeLog

Parameters:

principal - the authorized LDAP principal triggering the change

forward - LDIF of the change going to the next state

reverse - LDIF (anti-operation): the change required to revert this change

Returns:

the new revision reached after having applied the forward LDIF

Throws:

org.apache.directory.api.ldap.model.exception.LdapException

log

public ChangeLogEvent log(LdapPrincipal principal,
                          org.apache.directory.api.ldap.model.ldif.LdifEntry forward,
                          List<org.apache.directory.api.ldap.model.ldif.LdifEntry> reverses)
                   throws org.apache.directory.api.ldap.model.exception.LdapException

Records a change as a forward LDIF, some reverse changes to revert the change and the authorized principal triggering the revertable change event.

Specified by:

log in interface ChangeLog

Parameters:

principal - the authorized LDAP principal triggering the change

forward - LDIF of the change going to the next state

reverses - LDIF (anti-operation): the changes required to revert this change

Returns:

the new revision reached after having applied the forward LDIF

Throws:

org.apache.directory.api.ldap.model.exception.LdapException

isLogSearchSupported

public boolean isLogSearchSupported()

Returns whether or not this ChangeLogService supports searching for changes.

Specified by:

isLogSearchSupported in interface ChangeLog

Returns:

true if log searching is supported, false otherwise

isTagSearchSupported

public boolean isTagSearchSupported()

Returns whether or not this ChangeLogService supports searching for snapshot tags.

Specified by:

isTagSearchSupported in interface ChangeLog

Returns:

true if snapshot tag searching is supported, false otherwise

isTagStorageSupported

public boolean isTagStorageSupported()

Returns whether or not this ChangeLogService stores snapshot tags.

Specified by:

isTagStorageSupported in interface ChangeLog

Returns:

true if this ChangeLogService supports tag storage, false otherwise

getChangeLogSearchEngine

public ChangeLogSearchEngine getChangeLogSearchEngine()

Gets the change log query engine which would be used to ask questions about what changed, when, how and by whom. It may not be supported by all implementations. Some implementations may simply log changes without direct access to those changes from within the server.

Specified by:

getChangeLogSearchEngine in interface ChangeLog

Returns:

the change log query engine

getTagSearchEngine

public TagSearchEngine getTagSearchEngine()

Gets the tag search engine used to query the snapshots taken. If this ChangeLogService does not support a taggable and searchable store then an UnsupportedOperationException will result.

Specified by:

getTagSearchEngine in interface ChangeLog

Returns:

the snapshot query engine for this store

tag

public Tag tag(long revision,
               String description)
        throws Exception

Creates a tag for a snapshot of the server in a specific state at a revision. If the ChangeLog has a TaggableChangeLogStore then the tag is stored. If it does not then it's up to callers to track this tag since it will not be stored by this service.

Specified by:

tag in interface ChangeLog

Parameters:

revision - the revision to tag the snapshot

description - some information about what the snapshot tag represents

Returns:

the Tag associated with the revision

Throws:

Exception - if there is a problem taking a tag

IllegalArgumentException - if the revision is out of range (less than 0 and greater than the current revision)

tag

public Tag tag(long revision)
        throws Exception

Creates a tag for a snapshot of the server in a specific state at a revision. If the ChangeLog has a TaggableChangeLogStore then the tag is stored. If it does not then it's up to callers to track this tag since it will not be stored by this service.

Specified by:

tag in interface ChangeLog

Parameters:

revision - the revision to tag the snapshot

Returns:

the Tag associated with the revision

Throws:

Exception - if there is a problem taking a tag

IllegalArgumentException - if the revision is out of range (less than 0 and greater than the current revision)

tag

public Tag tag(String description)
        throws Exception

Creates a snapshot of the server at the current revision.

Specified by:

tag in interface ChangeLog

Parameters:

description - some information about what the snapshot tag represents

Returns:

the revision at which the tag is created

Throws:

Exception - if there is a problem taking a tag

tag

public Tag tag()
        throws Exception

Creates a snapshot of the server at the current revision.

Specified by:

tag in interface ChangeLog

Returns:

the revision at which the tag is created

Throws:

Exception - if there is a problem taking a tag

setEnabled

public void setEnabled(boolean enabled)

Enable or disable the ChangeLog service

Specified by:

setEnabled in interface ChangeLog

Parameters:

enabled - true to enable the service, flase to disable it

isEnabled

public boolean isEnabled()

Checks whether or not the change log has been enabled to track changes.

Specified by:

isEnabled in interface ChangeLog

Returns:

true if the change log is tracking changes, false otherwise

getLatest

public Tag getLatest()
              throws org.apache.directory.api.ldap.model.exception.LdapException

Specified by:

getLatest in interface ChangeLog

Returns:

The latest tag

Throws:

org.apache.directory.api.ldap.model.exception.LdapException

init

public void init(DirectoryService service)
          throws Exception

Initialize the ChangeLog system. We will initialize the associated store.

Specified by:

init in interface ChangeLog

Parameters:

service - The associated DirectoryService

Throws:

Exception

sync

public void sync()
          throws Exception

Flush the changes to disk

Specified by:

sync in interface ChangeLog

Throws:

Exception - If the flush failed

destroy

public void destroy()
             throws Exception

Destroy the changeLog

Specified by:

destroy in interface ChangeLog

Throws:

Exception

isExposed

public boolean isExposed()

Specified by:

isExposed in interface ChangeLog

Returns:

true if the changeLog system is visible by clients

setExposed

public void setExposed(boolean exposed)

Exposes the contents of ChangeLog to clients if set to true. Default setting is false.

Specified by:

setExposed in interface ChangeLog

Parameters:

exposed - true to expose the contents, false to not expose.

setPartitionSuffix

public void setPartitionSuffix(String suffix)

The prefix of the partition. Default value is ou=changelog.

Specified by:

setPartitionSuffix in interface ChangeLog

Parameters:

suffix - suffix value to be set for the changelog partition

setRevisionsContainerName

public void setRevisionsContainerName(String revContainerName)

The name of the revisions container under the partition. Default value is ou=revisions

Specified by:

setRevisionsContainerName in interface ChangeLog

Parameters:

revContainerName - the name of the revisions container

setTagsContainerName

public void setTagsContainerName(String tagContainerName)

The name of the tags container under the partition. Default value is ou=tags

Specified by:

setTagsContainerName in interface ChangeLog

Parameters:

tagContainerName - the name of the revisions container

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()