platform-vcm-home/docs/online/team3.1/logical-physical-mappings.html

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  some revision before the end of the Eclipse 3.1 development cycle.
  <h3>The Basic Resource Mapping API</h3>
  <p>This solution involves adding API to the Resources plugin that maps logical
-   elements to physical ones. The API is purposely simple with logical model manipulations
+   models elements to workspace (i.e. file system) resources. The API is purposely
-   omitted. A client can't use this interface to display logical models or gain
+   simple with logical model manipulations omitted. A client can't use this interface
-   any interesting additional knowledge about it. The API consists of the following
+   to display logical models or gain any interesting additional knowledge about
-   classes: </p>
+   it. It's purpose is simply to map one or more model elements to workspace resources.
+ </p>
+ <p>The API consists of the following classes: </p>
  <ul>
-   <li><strong>ResourceMapping</strong>: class to which logical model elements
+   <li><strong>ResourceMapping</strong>: The Class to which logical model elements
      adapt to indicate that the model corresponds to a set of resources in the
      workspace. The complete <code>ResourceMapping</code> class can be viewed <a href="http://dev.eclipse.org/viewcvs/index.cgi/org.eclipse.core.resources/src/org/eclipse/core/resources/mapping/ResourceMapping.java?rev=HEAD&content-type=text/vnd.viewcvs-markup">here</a>.
      The methods of interest are:
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+Line 47
      to which the resources in the traversal are associated with the originating
      model object. Resource traversals are provided to a client by a resource mapping
      in order to describe the contents of a model in sich a way that a repository
-     provider can perform its operations in as efficient a means as possible.</li>
+     provider can perform its operations in as efficient a means as possible. Methods
+     of interest are:
+     <ul>
+       <li><code>getResources()</code></li>
+       <li><code>getDepth()</code></li>
+     </ul>
+   </li>
    <li><strong>ResourceMappingContext</strong>: a context that is provided to the
-     resource mapping by the client. This context allows the logical model to determine
+     resource mapping by the client when obtaining traversals. This context allows
-     what the remote state of the model is so that the proper resources can be
+     the logical model to determine what the remote state of the model is so that
-     covered by the resource traversals returned by the resource mapping. The use
+     the proper resources can be covered by the resource traversals returned by
-     of the<code> <a href="http://dev.eclipse.org/viewcvs/index.cgi/org.eclipse.core.resources/src/org/eclipse/core/resources/mapping/ResourceMappingContext.java?rev=HEAD&content-type=text/vnd.viewcvs-markup">ResourceMappingContext</a></code>
+     the resource mapping. The use of the<code> <a href="http://dev.eclipse.org/viewcvs/index.cgi/org.eclipse.core.resources/src/org/eclipse/core/resources/mapping/ResourceMappingContext.java?rev=HEAD&content-type=text/vnd.viewcvs-markup">ResourceMappingContext</a></code>
      is a bit more complicated and is described <a href="#ResourceMappingContext">later</a>.</li>
  </ul>
  <p>There are two types of plugins that should be interested in resource mappings.
-   Those who provide a model that consists of or is persisted in resources in the
+   Those who provide a model that consists of, or is persisted in, resources in
-   workspace and those that want to perform operations of resources. The following
+   the workspace and those that want to perform operations on resources. The following
    two sections describe how to associate a resource mapping with a model object
    and how to contribute menus to objects that adapt to resource mappings.</p>
  <h4>Adapting a Model to a ResourceMapping</h4>
  <p>Plugins that adapted their model objects to <code>IResource</code> in order
-   to get resource specific object contributions shown in the context menu can
+   to get resource specific actions shown in the context menu can now adapt to
-   now adapt to <code>ResourceMapping</code> if a richer description of how the
+   <code>ResourceMapping</code> if a richer description of how the object adapts
-   object adapts to resources is benefitial. However, they are not required to
+   to resources is benefitial. However, they are not required to do so if there
-   do so if there is no benefit. For instance a Java class that now currently adapts
+   is no benefit. For instance a Java class that now currently adapts to <code>IFile</code>
-   to <code>IFile</code> need no adapt to <code>ResourceMapping</code> since nothing
+   need not adapt to <code>ResourceMapping</code> since nothing is gained. However,
-   is gained. However, a Java package shoudl adapt to <code>ResourceMapping</code>
+   a Java package should adapt to <code>ResourceMapping</code> in order to indicate
-   in order to indicate that the package is only the files in the corresponding
+   that the package is only the files in the corresponding folder and not the subfolders.</p>
-   folder and not the subfolders.</p>
+ <p>The preferred way to adapt model elements to a resource mapping is to use an
- <p>An adapter factory can be used to adapt model objects into resource mappings.
+   adapter factory. The following is the XML markup for contributing an adapter
-   The following is the XML markup for contributing an adapter factory in a plugin
+   factory in a plugin manifest. </p>
-   manifest. </p>
  <pre style="background-color: rgb(204, 204, 255);">   &lt;extension<br>         point=&quot;org.eclipse.core.runtime.adapters&quot;&gt;<br>      &lt;factory<br>            class=&quot;org.eclipse.example.library.logical.AdapterFactory&quot;<br>            adaptableType=&quot;org.eclipse.example.library.Book&quot;&gt;<br>         &lt;adapter type=&quot;org.eclipse.core.resources.mapping.ResourceMapping&quot;/&gt;<br>      &lt;/factory&gt;<br>      &lt;factory<br>            class=&quot;org.eclipse.example.library.logical.AdapterFactory&quot;<br>            adaptableType=&quot;org.eclipse.example.library.Library&quot;&gt;<br>         &lt;adapter type=&quot;org.eclipse.core.resources.mapping.ResourceMapping&quot;/&gt;<br>      &lt;/factory&gt;<br>      ...<br>   &lt;/extension&gt;</pre>
+ <p>The adapter factory implementation would look something like this:</p>
+ <pre style="background-color: rgb(204, 204, 255);">public class AdapterFactory implements IAdapterFactory {
+    public Object getAdapter(Object adaptableObject, Class adapterType) {
+       if((adaptableObject instanceof EObject) && adapterType == ResourceMapping.class) {
+          return new EMFResourceMapping((EObject)adaptableObject);
+       }
+       return null;
+    }
+    public Class[] getAdapterList() {
+       return new Class[] {ResourceMapping.class};
+    }
+ }</pre>
  <p>For popup menu contribuions, it is not required that the model objects implement
    the <code>IAdaptable</code> interface. However, if they do they must ensure
    that the Platform adapter manager is consulted. This can be done by either subclassing
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+Line 187
    file from a repository, the user would expect that any new images would be included.
    The getTraversals method for a ResourceMapping for the HTML file model would
    look something like this:</p>
- <pre style="background-color: rgb(204, 204, 255);">public class HTNLResourceMapping extends ResourceMapping {
+ <pre style="background-color: rgb(204, 204, 255);">public class HTMLResourceMapping extends ResourceMapping {
     private HTMLFile htmlFile;
     getTraversals(ResourceMappingContext context, IPorgressMonitor monitor) {
        IResource[] resources = htmlFile.getRsources();

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