question: private static String padString ( final String rawVal , final int maxLen ) { final int length = rawVal . length ( ) ; if ( maxLen == length ) { return rawVal ; } else if ( maxLen < length ) { return rawVal ; } else { final StringBuilder paddedString = new StringBuilder ( ) ; final int extraChars = maxLen - length ; for ( int jj = 0 ; jj < extraChars ; jj ++ ) { paddedString . append ( '0' ) ; } paddedString . append ( rawVal ) ; return paddedString . toString ( ) ; } }
target:  ensure any empty slots at start filled