Index: DisjunctionMaxQuery.java
===================================================================
--- DisjunctionMaxQuery.java	(revision 391800)
+++ DisjunctionMaxQuery.java	(working copy)
@@ -22,6 +22,7 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.Collection;
+import java.util.Set;
 
 /**
  * A query that generates the union of the documents produced by its subqueries, and that scores each document as the maximum
@@ -242,5 +243,18 @@
             + Float.floatToIntBits(tieBreakerMultiplier)
             + disjuncts.hashCode();
   }
+  
+  /**
+   * Expert: adds all terms occuring in this query to the terms set. Only
+   * works if this query is in its {@link #rewrite rewritten} form.
+   * 
+   * @throws UnsupportedOperationException if this query is not yet rewritten
+   */  
+  public void extractTerms(Set terms) {
+      for (int i = 0; i < disjuncts.size(); i++) {
+          ((Query)disjuncts.get(i)).extractTerms(terms);
+      }
+  }
+}
 
-}
+