minor cleanup on ETS operator
diff --git a/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/algebra/operators/logical/EmptyTupleSourceOperator.java b/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/algebra/operators/logical/EmptyTupleSourceOperator.java
index 710e02f..5872e6d 100644
--- a/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/algebra/operators/logical/EmptyTupleSourceOperator.java
+++ b/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/algebra/operators/logical/EmptyTupleSourceOperator.java
@@ -29,12 +29,6 @@
 
 public class EmptyTupleSourceOperator extends AbstractLogicalOperator {
 
-    // public final static EmptyTupleSourceOperator INSTANCE = new
-    // EmptyTupleSourceOperator();
-
-    public EmptyTupleSourceOperator() {
-    }
-
     @Override
     public LogicalOperatorTag getOperatorTag() {
         return LogicalOperatorTag.EMPTYTUPLESOURCE;