question: private String splitNameWithoutGzipExtension ( String split ) throws IOException { if ( split == null ) { throw new IOException ( "Path is not a split" ) ; } if ( split . endsWith ( ".gz" ) ) { return split . substring ( 0 , split . length ( ) - 3 ) ; } return split ; }
target:  Since we appended a gzip extension to the split file name we need to take it off to get the actual split.