Grid Element Creator

Identifier:

eu.geclipse.core.gridElementCreator

Since:

0.5

Description:

This extension point is the entry point into the g-Eclipse model. It defines element creators that are able to create Grid model elements from arbitrary Objects like IResources or URIs. These element creators are used to both create elements and to insert them into the model hierarchy.

Configuration Markup:

<!ELEMENT extension (creator+)>

<!ATTLIST extension

point CDATA #REQUIRED

id CDATA #IMPLIED

name CDATA #IMPLIED>

<!ELEMENT creator (source+ , target)>

<!ATTLIST creator

id CDATA #REQUIRED

name CDATA #REQUIRED

class CDATA #REQUIRED

wizard CDATA #IMPLIED>

id - A unique ID that is used to reference to this element creator extension.
name - A name of the creator that may be used to represent the creator in the UI, e.g. in wizard pages.
class - Implementation of the eu.geclipse.core.model.IGridElementCreator interface that is used to create Grid elements and to insert them into the Grid model hierarchy.
wizard - An optional wizard ID that may be used by the UI to specify initial arguments for a new Grid element.

<!ELEMENT source EMPTY>

<!ATTLIST source

class CDATA #REQUIRED

pattern CDATA #IMPLIED

priority CDATA #IMPLIED

default (true | false)

matcher CDATA #IMPLIED>

Specifies the source of the creator. The source of a creator is an arbitrary class (inheriting from java.lang.Object from which a Grid element can be created. Furthermore an optional pattern can be defined that will be matched against toString() of the source. As last step a matcher may be defined that may have a final look at the specified object. Only if all defined matching rules hold for the specified source object it is assumed that this creator potentially can create an IGridElement from the source object.

class - An arbitrary java.lang.Object from which this creator can create a Grid element.
pattern - An optional regular expression that may be used to further restrict the sources. If the source itself is for instance a java.io.File the pattern may be used to match the filename of the file. The pattern therefore is applied to the toString() method of the source. If this source element is declared to be the default source the pattern attribute may be interpreted as default value of the source, e.g. if this is a String or URI source.
priority - If more than one creator matches the requirements this field is used to decide which creator should be taken to create a grid model element. Values from 1 to 99 are supported. Values less than 1 will be treated as 1, values greater than 99 will be treated as 99. The default value is 50.
default - A boolean element determining if this is the default source for the element creator. There should either be no default source or exactly one default source. Specifying more than one default sources may result in undetermined behaviour. If this is the default resource the pattern attribute may be interpreted as default value, e.g. for a URI source.
matcher - This implementation of eu.geclipse.core.model.ICreatorSourceMatcher is used to match the source object against the element creator. A matcher is defined in addition to the class and pattern attributes. Only if both class and pattern do already match the object the matcher is also invoked. Only if all matching methods succeed this creator is assumed to be appropriate to create an element from the source.

<!ELEMENT target EMPTY>

<!ATTLIST target

name CDATA #REQUIRED

class CDATA #REQUIRED>

Specifies the target of the creator. The target of a creator is a class that implements eu.geclipse.core.model.IGridElement and that is created by a specific creator.

name -
class - A eu.geclipse.core.model.IGridElement that denotes the types of elements that are created by an element creator.

Examples:


<extension point="eu.geclipse.core.gridElementCreator">
  <creator
    class="eu.geclipse.core.model.impl.GenericVoCreator"
    name="Generic VO"
    wizard="eu.geclipse.ui.wizards.GenericVoWizard">
    <source
      class="org.eclipse.core.filesystem.IFileStore">
    </source>
    <target
      class="eu.geclipse.core.model.impl.GenericVirtualOrganization">
    </target>
  </creator>
</extension>

Supplied Implementation:

A core implementation of this extension point is for instance used for the Generic Virtual Organization.

Copyright (c) 2006, 2007 g-Eclipse Consortium

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 http://www.eclipse.org/legal/epl-v10.html.

Initial development of the original code was made for the g-Eclipse project founded by European Union project number: FP6-IST-034327 http://www.geclipse.eu.