Element Factories
Identifier:
org.eclipse.ui.elementFactories
Description:
This extension point is used to add element factories
to the workbench. An element factory is used to
recreate
IAdaptable objects which are
persisted during workbench shutdown.
As an example, the element factory is used to
persist editor input. The input for an
editor must implement
org.eclipse.ui.EditorInput.
The life cycle of an IEditorInput within
an editor has a number of phases.
-
The initial input for an editor is passed in during
editor creation.
-
On shutdown the workbench state is captured.
In this process the workbench will create a memento
for each open editor and its input. The input is
saved as a two part memento containing a factory ID
and any primitive data required to recreate the
element on startup. For more information see
the documentation on
org.eclipse.ui.IPersistableElement.
-
On startup the workbench state is read and the
editors from the previous session are recreated.
In this process the workbench will recreate the input
element for each open editor. To do this it will
map the original factory ID for the input element
to a concrete factory class defined in the registry.
If a mapping exists, and the factory class is valid,
an instance of the factory class is created. Then
the workbench asks the factory to recreate the original
element from the remaining primitive data within the
memento. The resulting IAdaptable is cast
to an IEditorInput and passed to the
new editor.
Configuration Markup:
<!ELEMENT extension (
factory*)>
<!ATTLIST extension
point CDATA #REQUIRED
id CDATA #IMPLIED
name CDATA #IMPLIED
>
-
point - a fully qualified identifier of the target extension point
-
id - an optional identifier of the extension instance
-
name - an optional name of the extension instance
<!ELEMENT factory EMPTY>
<!ATTLIST factory
id CDATA #REQUIRED
class CDATA #REQUIRED
>
-
id - a unique name that will be used to identify this factory.
-
class - a fully qualified name of a class that implements
org.eclipse.ui.IElementFactory
Examples:
The following is an example of an element factory extension:
<extension
point =
"org.eclipse.ui.elementFactories"
>
<factory
id =
"com.xyz.ElementFactory"
class=
"com.xyz.ElementFactory"
>
</factory>
</extension>
Supplied Implementation:
The workbench provides an
IResource factory.
Additional factories should be added to recreate other
IAdaptable types commonly found in other
object models, such as the Java Model.
Copyright (c) 2002, 2005 IBM Corporation and others.
All rights reserved. This program and the accompanying materials are made
available under the terms of the Eclipse Public License v1.0 which accompanies
this distribution, and is available at https://www.eclipse.org/legal/epl-v10.html