ALF-10980 CLONE - Opening and closing (not save) MS Project file via CIFS adds new version

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@32444 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/filesys/repo/ContentComparator.java

@@ -0,0 +1,21 @@
+package org.alfresco.filesys.repo;
+
+import java.io.File;
+import java.io.InputStream;
+
+import org.alfresco.service.cmr.repository.ContentReader;
+
+public interface ContentComparator
+{
+    /**
+     * Are the two content items equal?
+     * <p>
+     * For most cases a simple binary comparison is sufficient but some mimetypes 
+     * trivial changes need to be discarded.
+     * <p>
+     * @param existingContent
+     * @param newFile
+     * @return true content is equal, false content is different.
+     */
+    boolean isContentEqual(ContentReader existingContent, File file);
+}