setColumns(buffer.toString());
    public void setColumns(String colstring) {	if (colstring != null) {	    StringTokenizer tokens = new StringTokenizer(colstring, ",");	    String[] newcols = new String[tokens.countTokens()];	    int i=0;	    while (tokens.hasMoreTokens())		newcols[i++] = tokens.nextToken().trim();	    setColumns(newcols);	}    }