JDBC怎么读写B/CLOB

        Statement stmt = connection.createStatement();        ResultSet rs = stmt.executeQuery("SELECT col_blob FROM mysql_all_table");            if (rs.next()) {            // Get the BLOB from the result set            Blob blob = rs.getBlob("col_blob");                // Get the number bytes in the BLOB            long blobLength = blob.length();                // Get bytes from the BLOB in a byte array            int pos = 1;   // position is 1-based            int len = 10;            byte[] bytes = blob.getBytes(pos, len);                // Get bytes from the BLOB using a stream            InputStream is = blob.getBinaryStream();            int b = is.read();