public static String getFilePath(int docId, String extention) {
        int[] split = getSplit(docId);
        return split[0] + "/" + split[1] + "/" + split[2] + "." + extention;
    }
public static String getFilePath ( int docId , String extention ) { int [ ] split = getSplit ( docId ) ; return split [ 0 ] + "/" + split [ 1 ] + "/" + split [ 2 ] + "." + extention ; }
@param docId
usually PubMed id
@param extention
e.g. "gz", or "pdf" (WITHOUT dot!)
@return a path, e.g.:
<ul>
<li>2345678, "gz" -> "2/345/678.gz"</li>
<li>78, "pdf" -> "0/0/78.pdf"</li>
</ul>