@ Override public void beforeFirst ( ) { currentScan = null ; s1 . beforeFirst ( ) ; hasMore1 = s1 . next ( ) ; if ( s2 != null ) { s2 . beforeFirst ( ) ; hasMore2 = s2 . next ( ) ; } }
Positions the scan before the first record in sorted order . Internally it moves to the first record of each underlying scan . The variable currentScan is set to null indicating that there is no current scan .