minor fixes to remove warnings

git-svn-id: https://hyracks.googlecode.com/svn/trunk/hyracks@180 123451ca-8445-de46-9d55-352943316053
diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java
index 3b3c94e..6874f30 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDropOperatorNodePushable.java
@@ -10,8 +10,7 @@
 import edu.uci.ics.hyracks.storage.common.file.FileManager;
 
 public class BTreeDropOperatorNodePushable extends AbstractOperatorNodePushable {
-
-    private String btreeFileName;
+	
     private IBTreeRegistryProvider btreeRegistryProvider;
     private IBufferCacheProvider bufferCacheProvider;
     private IFileMappingProviderProvider fileMappingProviderProvider;