Fix for ALF-2118:

- Added new method to MimetypeService to retrieve a valid mimetype given any extension, handling case and missing values
 - Updated JUnit tests for MimetypeService methods
 - Fixed callers of MimetypeService to use new method to protect against varying case of file extensions (ALF-2118 root cause)

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@19400 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/service/cmr/repository/MimetypeService.java

@@ -31,7 +31,6 @@ import org.alfresco.service.PublicService;
  * This service interface provides support for Mimetypes.
  * 
  * @author Derek Hulley
- *
  */
 @PublicService
 public interface MimetypeService
@@ -41,11 +40,19 @@ public interface MimetypeService
      * 
      * @param mimetype a valid mimetype
      * @return Returns the default extension for the mimetype
-     * @throws AlfrescoRuntimeException if the mimetype doesn't exist
      */
     @NotAuditable
     public String getExtension(String mimetype);
 
+    /**
+     * Get the mimetype for the specified extension
+     * 
+     * @param extension a valid file extension
+     * @return Returns a valid mimetype if found, or null if does not exist
+     */
+    @NotAuditable
+    public String getMimetype(String extension);
+
     /**
      * Get all human readable mimetype descriptions indexed by mimetype extension
      *