# EMF Model Transaction Workspace Integration Overview

As a second part of the transaction framework there is a support layer for using the `TransactionalEditingDomain` in the context of an eclipse `IOperationHistory`. This support layer can be found in the `org.eclipse.emf.workspace` plugin and has the following main classes that can be used by clients:

1. The `WorkspaceEditingDomainFactory` can be used to create a new transactional editing domain that delegates it command execution, undo and redo to an `IOperationHistory` that is either provided by the client or retrieved from the `OperationHistoryFactory`. Any EMF-style commands executed on this special transactional editing domain's command stack will be wrapped and executed on the operation history.
2. All `IOperation`s that will be making changes to a workspace transactional editing domain can subclass the `AbstractEMFOperation` class in order to obtain the necessary write lock. Note that undo and redo is handled automatically because the changes made during the operation's execution are recorded. The `CompositeEMFOperation` allows clients to compose operations that change their editing domain and those that make changes to non-EMF objects. Client must not make changes to non-EMF objects within an AbstractEMFOperation because undo/redo is expected to be handled automatically by recording changes to EMF objects.
3. Clients can determine if an operation affects their EMF resource(s) by calling `ResourceUndoContext.getAffectedResources()`. This is particularly useful for `IOperationHistoryListener`s to determine whether or not a completed operation should be tagged with their own `IUndoContext` to signal that this operation should show up on their undo/redo menus.
4. A `WorkspaceSynchronizer` is provided to help clients keep their editing domains synchronized with changes that are being made to files in the eclipse workspace.

Please refer to the tutorial Workspace Integration Tutorial.

Copyright (c) 2006 IBM Corporation and others. All Rights Reserved.