1 files changed, 15 insertions, 26 deletions

diff --git a/src/mongo/db/storage/mmap_v1/record_store_v1_capped_iterator.h b/src/mongo/db/storage/mmap_v1/record_store_v1_capped_iterator.h
index 99f83b20e7a..de2b6fda5e3 100644
--- a/src/mongo/db/storage/mmap_v1/record_store_v1_capped_iterator.h
+++ b/src/mongo/db/storage/mmap_v1/record_store_v1_capped_iterator.h
@@ -40,32 +40,25 @@ namespace mongo {
     /**
      * This class iterates over a capped collection identified by 'ns'.
      * The collection must exist when the constructor is called.
-     *
-     * If start is not DiskLoc(), the iteration begins at that DiskLoc.
-     *
-     * If tailable is true, getNext() can be called after isEOF.  It will use the last valid
-     * returned DiskLoc and try to find the next record from that.
      */
-    class CappedRecordStoreV1Iterator : public RecordIterator {
+    class CappedRecordStoreV1Iterator final : public RecordCursor {
     public:
         CappedRecordStoreV1Iterator( OperationContext* txn,
                                      const CappedRecordStoreV1* collection,
-                                     const RecordId& start,
-                                     bool tailable,
-                                     const CollectionScanParams::Direction& dir );
-        virtual ~CappedRecordStoreV1Iterator() { }
+                                     bool forward );
 
-        // If this is a tailable cursor, isEOF could change its mind after a call to getNext().
-        virtual bool isEOF();
-        virtual RecordId getNext();
-        virtual RecordId curr();
+        boost::optional<Record> next() final;
+        boost::optional<Record> seekExact(const RecordId& id) final;
+        void savePositioned() final;
+        bool restore(OperationContext* txn) final;
+        void invalidate(const RecordId& dl) final;
+        std::unique_ptr<RecordFetcher> fetcherForNext() const final;
+        std::unique_ptr<RecordFetcher> fetcherForId(const RecordId& id) const final;
 
-        virtual void invalidate(const RecordId& dl);
-        virtual void saveState();
-        virtual bool restoreState(OperationContext* txn);
-
-        virtual RecordData dataFor( const RecordId& loc ) const;
     private:
+        void advance();
+        bool isEOF() { return _curr.isNull(); }
+
         /**
          * Internal collection navigation helper methods.
          */
@@ -82,20 +75,16 @@ namespace mongo {
         OperationContext* _txn;
 
         // The collection we're iterating over.
-        const CappedRecordStoreV1* _recordStore;
+        const CappedRecordStoreV1* const _recordStore;
 
         // The result returned on the next call to getNext().
         DiskLoc _curr;
 
-        // If we're tailable, we try to progress from the last valid result when we hit the end.
-        DiskLoc _prev;
-        bool _tailable;
-
-        CollectionScanParams::Direction _direction;
+        const bool _forward;
 
         // If invalidate kills the DiskLoc we need to move forward, we kill the iterator.  See the
         // comment in the body of invalidate(...).
-        bool _killedByInvalidate;
+        bool _killedByInvalidate = false;
     };
 
 }  // namespace mongo