Index: src/org/eclipse/core/internal/content/ContentTypeMatcher.java
===================================================================
RCS file: /home/eclipse/org.eclipse.core.runtime/src/org/eclipse/core/internal/content/ContentTypeMatcher.java,v
retrieving revision 1.1
diff -u -r1.1 ContentTypeMatcher.java
--- src/org/eclipse/core/internal/content/ContentTypeMatcher.java	4 Mar 2005 22:18:54 -0000	1.1
+++ src/org/eclipse/core/internal/content/ContentTypeMatcher.java	8 Mar 2005 16:04:53 -0000
@@ -11,6 +11,8 @@
 package org.eclipse.core.internal.content;
 
 import java.io.*;
+import java.util.ArrayList;
+import java.util.List;
 import org.eclipse.core.runtime.QualifiedName;
 import org.eclipse.core.runtime.content.*;
 
@@ -54,6 +56,31 @@
 	 */
 	public IContentType[] findContentTypesFor(String fileName) {
 		return getCatalog().findContentTypesFor(fileName, policy);
+	}
+
+	public Object[] findRelatedObjects(IContentType type, String fileName, IRelatedRegistry registry) {
+		List allRelated = new ArrayList();
+		// first add any objects directly related to the content type
+		Object[] related = registry.getRelatedObjects(type);
+		for (int i = 0; i < related.length; i++)
+			allRelated.add(related[i]);
+		// backward compatibility requested - add any objects related to the file name
+		if (fileName != null) {
+			related = registry.getRelatedObjects(fileName);
+			for (int i = 0; i < related.length; i++)
+				if (!allRelated.contains(related[i]))
+					// we don't want to return duplicates
+					allRelated.add(related[i]);
+		}
+		// now add any indirectly related objects, walking up the content type hierarchy 
+		while ((type = type.getBaseType()) != null) {
+			related = registry.getRelatedObjects(type);
+			for (int i = 0; i < related.length; i++)
+				if (!allRelated.contains(related[i]))
+					// we don't want to return duplicates					
+					allRelated.add(related[i]);
+		}
+		return allRelated.toArray();
 	}
 
 	private ContentTypeCatalog getCatalog() {
Index: src/org/eclipse/core/runtime/content/IContentTypeMatcher.java
===================================================================
RCS file: /home/eclipse/org.eclipse.core.runtime/src/org/eclipse/core/runtime/content/IContentTypeMatcher.java,v
retrieving revision 1.1
diff -u -r1.1 IContentTypeMatcher.java
--- src/org/eclipse/core/runtime/content/IContentTypeMatcher.java	4 Mar 2005 22:18:54 -0000	1.1
+++ src/org/eclipse/core/runtime/content/IContentTypeMatcher.java	8 Mar 2005 16:04:53 -0000
@@ -23,6 +23,44 @@
  * @since 3.1
  */
 public interface IContentTypeMatcher {
+
+	/**
+	 * A client-provided registry containing objects that are related to content types. Implementations
+	 * of this interface collaborate with the content type infrastructure in order to support lookup 
+	 * of content type related objects. 
+	 * <p>
+	 * Clients may implement this interface.
+	 * </p>
+	 * 
+	 * @see IContentTypeMatcher#findRelatedObjects(IContentType, String, IRelatedRegistry)
+	 */
+	interface IRelatedRegistry {
+		/**
+		 * Returns all objects in this client-provided registry that are directly related to the given
+		 * content type.
+		 * 
+		 * @param type a content type
+		 * @return an array containing all objects directly related to the given content type
+		 */
+		Object[] getRelatedObjects(IContentType type);
+
+		/**
+		 * Returns all objects in this client-provided registry that are directly related to the given
+		 * file name.
+		 * <p>
+		 * This method is optional. It only has to be implemented if this registry supports 
+		 * file name based association in addition to content type based association. 
+		 * Otherwise, it can throw <code>UnsupportedOperationException</code>.
+		 * </p>
+		 * 
+		 * @param fileName a file name
+		 * @return an array containing all objects directly related to the given file name
+		 * @throws UnsupportedOperationException if this registry does not support file
+		 * name based association
+		 */
+		Object[] getRelatedObjects(String fileName);
+	}
+
 	/**
 	 * Returns the preferred content type for the given contents and file name.
 	 * <p>
@@ -90,6 +128,24 @@
 	 * @return all content types associated to the given file spec
 	 */
 	public IContentType[] findContentTypesFor(String fileName);
+
+	/**
+	 * Returns all objects in the given content type-related registry  that are 
+	 * related to the content type and file name specified. This method will walk 
+	 * the content type hierarchy tree up to a root content type, collecting all related
+	 * objects from the given registry. 
+	 * <p>
+	 * The file name is optional, and has to be omitted if the given registry 
+	 * does not support file name based associations.  
+	 * </p>
+	 * 
+	 * @param type a content type
+	 * @param fileName the name of the file, or <code>null</code> 
+	 * @param registry a related registry
+	 * @return all objects in the related registry that are associated to the 
+	 * content type
+	 */
+	public Object[] findRelatedObjects(IContentType type, String fileName, IRelatedRegistry registry);
 
 	/**
 	 * Tries to obtain a description for the given contents and file name.