org.sourceforge.jemm.database.components
Class BaseDatabase

java.lang.Object
  org.sourceforge.jemm.database.components.BaseDatabase

All Implemented Interfaces:

Database

Direct Known Subclasses:

BDbDatabase, MemoryDatabase

public abstract class BaseDatabase
extends java.lang.Object
implements Database

Field Summary

protected DefaultDBAtomicIntTypeHandler	atomicIntHandler
protected DBClassHandler	classHandler
protected DBClientRefHandler	clientRefHandler
protected DatabaseDebugIF	debugHandler
protected DBEnumHandler	enumHandler
protected DBGarbageSweeper	gcHandler
protected DefaultDBListTypeHandler	listHandler
protected DefaultDBMapTypeHandler	mapHandler
protected DBObjectHandler	objectHandler
protected ObjectStatusListener	objectStatusListener
protected DBRootHandler	rootHandler
protected DefaultDBSetTypeHandler	setHandler
protected StorageEngine	storageEngine
protected java.util.Map<ClassId,TypeHandler>	typeHandlers
protected DBUserLockHandler	userLockHandler

Constructor Summary

BaseDatabase(StorageEngine storageEngine, GCMode gcMode)

Method Summary

void	acquireLock(ClientThreadId threadId, ID jemmId) Asynchronous request to acquire a lock.
void	clientDisconnect(ClientId clientId) Notification that the given client has disconnected, this call is only used on multi-client servers, allowing the server to free up resources associated with the client.
ClassInfo	getClassInfo(ClientId clientId, ClassId classId) Returns the class information for the given class id.
DatabaseDebugIF	getDebugInterface() Returns a debug interface for this database, or null if not available.
EnumInfo	getEnumInfo(ClientId clientId, EnumId enumId) Returns the information about the given enumeration.
GetObjectResp	getObject(ClientId clientId, ID jemmId) Retrieves an object's information from the database.
ID	getRoot(ClientId clientId, java.lang.String rootName) Returns the object stored in the persistent root called 'rootName'
ID	newObject(ClientId clientId, ClassId classId) Notification of a new user object creation by the client.
TypeResponse<?>	processTypeRequest(ClientId clientId, ClassId classId, ID objId, TypeRequest<?> request) Process a request from a jemm type implementation.
void	referenceCleared(ClientId clientId, ID... ids) Asynchronous notification that the client has de-referenced the given id.
ClassId	registerClass(ClientId clientId, ClassInfo classInfo) Register a user class.
EnumId	registerEnum(ClientId clientId, EnumInfo enumInfo) Register an enumerated type.
void	releaseLock(ClientThreadId threadId, ID jemmId) Release the given lock held by the thread.
void	removeLockAcquiredListener(ClientId clientId) Remove a lock listener
void	setClientLockAcquiredListener(ClientId clientId, LockAcquiredListener listener) Register a lock listener
void	setRoot(ClientId clientId, java.lang.String rootName, ID newValue) Set the persistent root reference to the given object.
ID	setRootIfNull(ClientId clientId, java.lang.String rootName, ID newValue) Sets the persistent root reference to the given object, if the root is currently null.
void	shutdown()
ObjectSyncResp	synchroniseObject(ClientId clientId, ID objectId, ObjectSyncData syncData) Synchronise a client held object with the server.

Methods inherited from class java.lang.Object

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

Field Detail

classHandler

protected final DBClassHandler classHandler

enumHandler

protected final DBEnumHandler enumHandler

objectHandler

protected final DBObjectHandler objectHandler

userLockHandler

protected final DBUserLockHandler userLockHandler

rootHandler

protected final DBRootHandler rootHandler

debugHandler

protected final DatabaseDebugIF debugHandler

clientRefHandler

protected final DBClientRefHandler clientRefHandler

gcHandler

protected final DBGarbageSweeper gcHandler

listHandler

protected DefaultDBListTypeHandler listHandler

setHandler

protected DefaultDBSetTypeHandler setHandler

mapHandler

protected DefaultDBMapTypeHandler mapHandler

atomicIntHandler

protected DefaultDBAtomicIntTypeHandler atomicIntHandler

objectStatusListener

protected final ObjectStatusListener objectStatusListener

storageEngine

protected StorageEngine storageEngine

typeHandlers

protected java.util.Map<ClassId,TypeHandler> typeHandlers

Constructor Detail

BaseDatabase

public BaseDatabase(StorageEngine storageEngine,
                    GCMode gcMode)

Method Detail

setClientLockAcquiredListener

public void setClientLockAcquiredListener(ClientId clientId,
                                          LockAcquiredListener listener)

Description copied from interface: Database

Register a lock listener

Specified by:

setClientLockAcquiredListener in interface Database

Parameters:

clientId - The id of the client registering for lock notifications.

listener - The listener to register.

acquireLock

public void acquireLock(ClientThreadId threadId,
                        ID jemmId)

Description copied from interface: Database

Asynchronous request to acquire a lock. This method will return immediately, but the caller should wait until notified by the LockAcquiredListener callback.

Specified by:

acquireLock in interface Database

Parameters:

threadId - The requesting thread.

jemmId - The id of the object to lock.

getClassInfo

public ClassInfo getClassInfo(ClientId clientId,
                              ClassId classId)

Description copied from interface: Database

Returns the class information for the given class id.

Specified by:

getClassInfo in interface Database

Parameters:

clientId - The id of the requesting client.

classId - The id of the held class.

Returns:

The class information for the held class.

getEnumInfo

public EnumInfo getEnumInfo(ClientId clientId,
                            EnumId enumId)

Description copied from interface: Database

Returns the information about the given enumeration.

Specified by:

getEnumInfo in interface Database

Parameters:

clientId - The id of the requesting client.

enumId - The id of the enumerated type.

Returns:

The classname of the registered enum type.

getObject

public GetObjectResp getObject(ClientId clientId,
                               ID jemmId)

Description copied from interface: Database

Retrieves an object's information from the database.

Specified by:

getObject in interface Database

Parameters:

clientId - The id of the requesting client.

jemmId - The id of the object to retrieve.

Returns:

The object information (class type, field values etc.).

getRoot

public ID getRoot(ClientId clientId,
                  java.lang.String rootName)

Description copied from interface: Database

Returns the object stored in the persistent root called 'rootName'

Specified by:

getRoot in interface Database

Parameters:

clientId - The id of the requesting client.

rootName - The name of the persistent root.

Returns:

The ID of the object stored in the persistent root, or null if none.

newObject

public ID newObject(ClientId clientId,
                    ClassId classId)

Description copied from interface: Database

Notification of a new user object creation by the client.

Specified by:

newObject in interface Database

Parameters:

clientId - The id of the requesting client.

classId - The class id of the new object (must be previously registered).

Returns:

The ID assigned to the new object.

referenceCleared

public void referenceCleared(ClientId clientId,
                             ID... ids)

Description copied from interface: Database

Asynchronous notification that the client has de-referenced the given id.

Specified by:

referenceCleared in interface Database

Parameters:

clientId - The client who is no longer referencing 'id'

ids - The ID that has been de-referenced.

registerClass

public ClassId registerClass(ClientId clientId,
                             ClassInfo classInfo)
                      throws StructureModifiedException

Description copied from interface: Database

Register a user class.

Specified by:

registerClass in interface Database

Parameters:

clientId - The registering client.

classInfo - The information about the loaded user class (name/fields).

Returns:

The class id of the registered class.

Throws:

StructureModifiedException - if the class has been modified and the Database does not accept the change

registerEnum

public EnumId registerEnum(ClientId clientId,
                           EnumInfo enumInfo)
                    throws StructureModifiedException

Description copied from interface: Database

Register an enumerated type.

Specified by:

registerEnum in interface Database

Parameters:

clientId - The identity of the registering client.

enumInfo - The EnumInfo describing the enumerated type.

Returns:

Returns the id of the registered enum type.

Throws:

StructureModifiedException - If a modification to the enum is detected.

releaseLock

public void releaseLock(ClientThreadId threadId,
                        ID jemmId)

Description copied from interface: Database

Release the given lock held by the thread.

Specified by:

releaseLock in interface Database

Parameters:

threadId - The thread currently holding the lock.

jemmId - The id of the object to release.

removeLockAcquiredListener

public void removeLockAcquiredListener(ClientId clientId)

Description copied from interface: Database

Remove a lock listener

Specified by:

removeLockAcquiredListener in interface Database

Parameters:

clientId - The lock listener to remove.

setRoot

public void setRoot(ClientId clientId,
                    java.lang.String rootName,
                    ID newValue)

Description copied from interface: Database

Set the persistent root reference to the given object.

Specified by:

setRoot in interface Database

Parameters:

clientId - The id of the requesting client.

rootName - The name of the persistent root.

newValue - The new value of the root.

setRootIfNull

public ID setRootIfNull(ClientId clientId,
                        java.lang.String rootName,
                        ID newValue)

Description copied from interface: Database

Sets the persistent root reference to the given object, if the root is currently null. This is an atomic operation.

Specified by:

setRootIfNull in interface Database

Parameters:

clientId - The id of the requesting client.

rootName - The name of the persistent root.

newValue - The new value of the root.

Returns:

The old value if it was not null, or the recently set value.

synchroniseObject

public ObjectSyncResp synchroniseObject(ClientId clientId,
                                        ID objectId,
                                        ObjectSyncData syncData)

Description copied from interface: Database

Synchronise a client held object with the server. Passing in the current client version and any updated fields this method returns the new version number of the object and any fields updated remotely (by another client).

Specified by:

synchroniseObject in interface Database

Parameters:

clientId - The id of the requesting client.

objectId - The id of the object.

syncData - The object synchronisation data (client version, updated fields)

Returns:

Returned synchronisation information, (new version number and updated fields).

getDebugInterface

public DatabaseDebugIF getDebugInterface()

Description copied from interface: Database

Returns a debug interface for this database, or null if not available.

Specified by:

getDebugInterface in interface Database

Returns:

The debug interface for this database, or null if not available.

shutdown

public void shutdown()

clientDisconnect

public void clientDisconnect(ClientId clientId)

Description copied from interface: Database

Notification that the given client has disconnected, this call is only used on multi-client servers, allowing the server to free up resources associated with the client.

Specified by:

clientDisconnect in interface Database

Parameters:

clientId - The id of the client that has disconnected.

processTypeRequest

public TypeResponse<?> processTypeRequest(ClientId clientId,
                                          ClassId classId,
                                          ID objId,
                                          TypeRequest<?> request)

Description copied from interface: Database

Process a request from a jemm type implementation. This is a generic call where a package of data is passed to database the type handler and a response is returned.

Specified by:

processTypeRequest in interface Database

Parameters:

clientId - The id of the requesting client.

classId - The id of the class making the request.

objId - The target object.

request - The request data.

Returns:

The response data supplied by the type handler.