Index: DataObjectPool.java
===================================================================
RCS file: /cvs/openide/src/org/openide/loaders/DataObjectPool.java,v
--- DataObjectPool.java		1.74
+++ DataObjectPool.java	
@@ -873,0 +873,8 @@ 
+                
+                // attempt to fix #30559
+                if (reenterCount>0 && s.size() == 1) {
+                    if (files != null && files.contains(s.iterator().next())) {
+                        return new HashSet();
+                    }
+                }
+