org.sourceforge.jemm.database.remote.client
Class RemoteDatabase

java.lang.Object
  org.sourceforge.jemm.database.remote.client.RemoteDatabase

All Implemented Interfaces:

Database

public class RemoteDatabase
extends java.lang.Object
implements Database

RemoteDatabase is the client side of a remote client/server pairing.

Author:

Rory Graves

Field Summary

protected ClientId	listenerClientId
protected LockAcquiredListener	lockListener

Constructor Summary

RemoteDatabase(ClientConnectionFactory clientFactory)
Create a remote database instance.

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 id) 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 id) 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() Shutdown the connection to the remote server.
ObjectSyncResp	synchroniseObject(ClientId clientId, ID jemmId, 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

listenerClientId

protected ClientId listenerClientId

lockListener

protected LockAcquiredListener lockListener

Constructor Detail

RemoteDatabase

public RemoteDatabase(ClientConnectionFactory clientFactory)
               throws ConnectionException

Create a remote database instance.

Parameters:

clientFactory - The connection factory used to connect to the remote server instance.

Throws:

ConnectionException - On error connecting to the remote server

Method Detail

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.

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.

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 id)

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.

id - 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 id)

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.

id - 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.

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.

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 jemmId,
                                        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.

jemmId - The id of the object.

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

Returns:

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

shutdown

public void shutdown()

Shutdown the connection to the remote server.

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.