diff --git a/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsAndPositionsEnum.java b/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsAndPositionsEnum.java
index e4e89bf..683b2c3 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsAndPositionsEnum.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsAndPositionsEnum.java
@@ -53,7 +53,7 @@ public final class MappingMultiDocsAndPositionsEnum extends DocsAndPositionsEnum
   }
 
   @Override
-  public int freq() {
+  public int freq() throws IOException {
     return current.freq();
   }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsEnum.java b/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsEnum.java
index 0319e1d..8a9bb79 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsEnum.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/MappingMultiDocsEnum.java
@@ -52,7 +52,7 @@ public final class MappingMultiDocsEnum extends DocsEnum {
   }
 
   @Override
-  public int freq() {
+  public int freq() throws IOException {
     return current.freq();
   }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xFields.java b/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xFields.java
index 621fe44..3d153d6 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xFields.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xFields.java
@@ -1024,7 +1024,7 @@ class Lucene3xFields extends FieldsProducer {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return docs.freq();
     }
 
@@ -1071,7 +1071,7 @@ class Lucene3xFields extends FieldsProducer {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return pos.freq();
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xTermVectorsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xTermVectorsReader.java
index c66e058..1df5ca9 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xTermVectorsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/lucene3x/Lucene3xTermVectorsReader.java
@@ -528,7 +528,7 @@ class Lucene3xTermVectorsReader extends TermVectorsReader {
     private Bits liveDocs;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
@@ -574,7 +574,7 @@ class Lucene3xTermVectorsReader extends TermVectorsReader {
     private int[] endOffsets;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       if (positions != null) {
         return positions.length;
       } else {
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40PostingsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40PostingsReader.java
index 0eb36ae..7bf74d7 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40PostingsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40PostingsReader.java
@@ -351,7 +351,7 @@ public class Lucene40PostingsReader extends PostingsReaderBase {
     }
     
     @Override
-    public final int freq() {
+    public final int freq() throws IOException {
       assert !indexOmitsTF;
       return freq;
     }
@@ -770,7 +770,7 @@ public class Lucene40PostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
@@ -989,7 +989,7 @@ public class Lucene40PostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40TermVectorsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40TermVectorsReader.java
index c0420d1..e44713b 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40TermVectorsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40TermVectorsReader.java
@@ -549,7 +549,7 @@ public class Lucene40TermVectorsReader extends TermVectorsReader {
     private Bits liveDocs;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
@@ -595,7 +595,7 @@ public class Lucene40TermVectorsReader extends TermVectorsReader {
     private int[] endOffsets;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       if (positions != null) {
         return positions.length;
       } else {
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/memory/MemoryPostingsFormat.java b/lucene/core/src/java/org/apache/lucene/codecs/memory/MemoryPostingsFormat.java
index 8badc9b..1453252 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/memory/MemoryPostingsFormat.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/memory/MemoryPostingsFormat.java
@@ -424,7 +424,7 @@ public class MemoryPostingsFormat extends PostingsFormat {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       assert indexOptions != IndexOptions.DOCS_ONLY;
       return freq;
     }
@@ -624,7 +624,7 @@ public class MemoryPostingsFormat extends PostingsFormat {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
   }
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/pulsing/PulsingPostingsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/pulsing/PulsingPostingsReader.java
index 18bd588..644e485 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/pulsing/PulsingPostingsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/pulsing/PulsingPostingsReader.java
@@ -356,7 +356,7 @@ public class PulsingPostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       assert indexOptions != IndexOptions.DOCS_ONLY;
       return freq;
     }
@@ -462,7 +462,7 @@ public class PulsingPostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/sep/SepPostingsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/sep/SepPostingsReader.java
index 533fd2f..6424fe3 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/sep/SepPostingsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/sep/SepPostingsReader.java
@@ -423,7 +423,7 @@ public class SepPostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       assert !omitTF;
       return freq;
     }
@@ -601,7 +601,7 @@ public class SepPostingsReader extends PostingsReaderBase {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return freq;
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextFieldsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextFieldsReader.java
index c3b252d..ec04e9a 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextFieldsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextFieldsReader.java
@@ -269,7 +269,7 @@ class SimpleTextFieldsReader extends FieldsProducer {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       assert !omitTF;
       return tf;
     }
@@ -370,7 +370,7 @@ class SimpleTextFieldsReader extends FieldsProducer {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return tf;
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextTermVectorsReader.java b/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextTermVectorsReader.java
index 03d6825..c7c8dc7 100644
--- a/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextTermVectorsReader.java
+++ b/lucene/core/src/java/org/apache/lucene/codecs/simpletext/SimpleTextTermVectorsReader.java
@@ -400,7 +400,7 @@ public class SimpleTextTermVectorsReader extends TermVectorsReader {
     private Bits liveDocs;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       assert freq != -1;
       return freq;
     }
@@ -447,7 +447,7 @@ public class SimpleTextTermVectorsReader extends TermVectorsReader {
     private int[] endOffsets;
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       if (positions != null) {
         return positions.length;
       } else {
diff --git a/lucene/core/src/java/org/apache/lucene/index/DocsEnum.java b/lucene/core/src/java/org/apache/lucene/index/DocsEnum.java
index e8d97ad..c0abe19 100644
--- a/lucene/core/src/java/org/apache/lucene/index/DocsEnum.java
+++ b/lucene/core/src/java/org/apache/lucene/index/DocsEnum.java
@@ -17,6 +17,8 @@ package org.apache.lucene.index;
  * limitations under the License.
  */
 
+import java.io.IOException;
+
 import org.apache.lucene.search.DocIdSetIterator;
 import org.apache.lucene.util.AttributeSource;
 
@@ -29,8 +31,9 @@ public abstract class DocsEnum extends DocIdSetIterator {
 
   /** Returns term frequency in the current document.  Do
    *  not call this before {@link #nextDoc} is first called,
-   *  nor after {@link #nextDoc} returns NO_MORE_DOCS. */
-  public abstract int freq();
+   *  nor after {@link #nextDoc} returns NO_MORE_DOCS. 
+   * @throws IOException TODO*/
+  public abstract int freq() throws IOException;
   
   /** Returns the related attributes. */
   public AttributeSource attributes() {
diff --git a/lucene/core/src/java/org/apache/lucene/index/FilterAtomicReader.java b/lucene/core/src/java/org/apache/lucene/index/FilterAtomicReader.java
index cc67c40..e0c4b58 100644
--- a/lucene/core/src/java/org/apache/lucene/index/FilterAtomicReader.java
+++ b/lucene/core/src/java/org/apache/lucene/index/FilterAtomicReader.java
@@ -225,7 +225,7 @@ public class FilterAtomicReader extends AtomicReader {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return in.freq();
     }
 
@@ -259,7 +259,7 @@ public class FilterAtomicReader extends AtomicReader {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return in.freq();
     }
 
diff --git a/lucene/core/src/java/org/apache/lucene/index/MultiDocsAndPositionsEnum.java b/lucene/core/src/java/org/apache/lucene/index/MultiDocsAndPositionsEnum.java
index dd6f263..e515a2d 100644
--- a/lucene/core/src/java/org/apache/lucene/index/MultiDocsAndPositionsEnum.java
+++ b/lucene/core/src/java/org/apache/lucene/index/MultiDocsAndPositionsEnum.java
@@ -69,7 +69,7 @@ public final class MultiDocsAndPositionsEnum extends DocsAndPositionsEnum {
   }
 
   @Override
-  public int freq() {
+  public int freq() throws IOException {
     return current.freq();
   }
 
diff --git a/lucene/core/src/java/org/apache/lucene/index/MultiDocsEnum.java b/lucene/core/src/java/org/apache/lucene/index/MultiDocsEnum.java
index c90ab1d..2597c7c 100644
--- a/lucene/core/src/java/org/apache/lucene/index/MultiDocsEnum.java
+++ b/lucene/core/src/java/org/apache/lucene/index/MultiDocsEnum.java
@@ -69,7 +69,7 @@ public final class MultiDocsEnum extends DocsEnum {
   }
 
   @Override
-  public int freq() {
+  public int freq() throws IOException {
     return current.freq();
   }
 
diff --git a/lucene/core/src/java/org/apache/lucene/search/MultiPhraseQuery.java b/lucene/core/src/java/org/apache/lucene/search/MultiPhraseQuery.java
index 2dbc77e..e008c19 100644
--- a/lucene/core/src/java/org/apache/lucene/search/MultiPhraseQuery.java
+++ b/lucene/core/src/java/org/apache/lucene/search/MultiPhraseQuery.java
@@ -568,7 +568,7 @@ class UnionDocsAndPositionsEnum extends DocsAndPositionsEnum {
   }
 
   @Override
-  public final int freq() {
+  public final int freq() throws IOException {
     return _freq;
   }
 
diff --git a/lucene/core/src/java/org/apache/lucene/search/TermScorer.java b/lucene/core/src/java/org/apache/lucene/search/TermScorer.java
index e5f93d1..ba638a5 100644
--- a/lucene/core/src/java/org/apache/lucene/search/TermScorer.java
+++ b/lucene/core/src/java/org/apache/lucene/search/TermScorer.java
@@ -51,7 +51,7 @@ final class TermScorer extends Scorer {
   }
 
   @Override
-  public float freq() {
+  public float freq() throws IOException {
     return docsEnum.freq();
   }
 
@@ -66,7 +66,7 @@ final class TermScorer extends Scorer {
   }
   
   @Override
-  public float score() {
+  public float score() throws IOException {
     assert docID() != NO_MORE_DOCS;
     return docScorer.score(docsEnum.docID(), docsEnum.freq());  
   }
diff --git a/lucene/memory/src/java/org/apache/lucene/index/memory/MemoryIndex.java b/lucene/memory/src/java/org/apache/lucene/index/memory/MemoryIndex.java
index d6615bc..977a87d 100644
--- a/lucene/memory/src/java/org/apache/lucene/index/memory/MemoryIndex.java
+++ b/lucene/memory/src/java/org/apache/lucene/index/memory/MemoryIndex.java
@@ -945,7 +945,7 @@ public class MemoryIndex {
       }
 
       @Override
-      public int freq() {
+      public int freq() throws IOException {
         return positions.size();
       }
     }
@@ -987,7 +987,7 @@ public class MemoryIndex {
       }
 
       @Override
-      public int freq() {
+      public int freq() throws IOException {
         return positions.size() / stride;
       }
 
diff --git a/lucene/test-framework/src/java/org/apache/lucene/codecs/ramonly/RAMOnlyPostingsFormat.java b/lucene/test-framework/src/java/org/apache/lucene/codecs/ramonly/RAMOnlyPostingsFormat.java
index f23d0fc..896f72a 100644
--- a/lucene/test-framework/src/java/org/apache/lucene/codecs/ramonly/RAMOnlyPostingsFormat.java
+++ b/lucene/test-framework/src/java/org/apache/lucene/codecs/ramonly/RAMOnlyPostingsFormat.java
@@ -439,7 +439,7 @@ public class RAMOnlyPostingsFormat extends PostingsFormat {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return current.positions.length;
     }
 
@@ -487,7 +487,7 @@ public class RAMOnlyPostingsFormat extends PostingsFormat {
     }
 
     @Override
-    public int freq() {
+    public int freq() throws IOException {
       return current.positions.length;
     }