Index: org/apache/lucene/search/EmptyDocIdSet.java
===================================================================
--- org/apache/lucene/search/EmptyDocIdSet.java	(revision 0)
+++ org/apache/lucene/search/EmptyDocIdSet.java	(revision 0)
@@ -0,0 +1,47 @@
+package org.apache.lucene.search;
+
+import java.io.IOException;
+
+public final class EmptyDocIdSet extends DocIdSet {
+  private static final EmptyDocIdSet instance = new EmptyDocIdSet();
+  
+  public static EmptyDocIdSet getInstance(){
+    return instance;  
+  }
+  
+  private EmptyDocIdSet(){
+	  
+  }
+  
+  @Override
+  public DocIdSetIterator iterator() {
+    return EmptyDocIdSetIterator.instance;
+  }
+
+  public static final class EmptyDocIdSetIterator extends DocIdSetIterator
+  {
+    private static final EmptyDocIdSetIterator instance = new EmptyDocIdSetIterator();
+    
+    public static EmptyDocIdSetIterator getInstance(){
+      return instance;
+    }
+    
+    private EmptyDocIdSetIterator(){    	
+    }
+    
+    @Override
+    public int doc() {
+	  return -1;
+    }
+
+    @Override
+    public boolean next() throws IOException {
+	  return false;
+    }
+
+    @Override
+    public boolean skipTo(int target) throws IOException {
+    	return false;
+    }	  
+  }
+}