code: public static void writePRJ(Connection connection, int srid, File fileName) throws SQLException, FileNotFoundException {
          if (srid != 0) {
              StringBuilder sb = new StringBuilder("SELECT SRTEXT FROM ");
              sb.append("PUBLIC.SPATIAL_REF_SYS ").append(" WHERE SRID = ?");
              PreparedStatement ps = connection.prepareStatement(sb.toString());
              ps.setInt(1, srid);
              PrintWriter printWriter = null;
              ResultSet rs = null;
              try {
                  rs = ps.executeQuery();
                  if (rs.next()) {
                      printWriter = new PrintWriter(fileName);
                      printWriter.println(rs.getString(1));
                  } else {
                      log.warn("This SRID { "+ srid +" } is not supported. \n The PRJ file won't be created.");
                  }
              } finally {
                  if (printWriter != null) {
                      printWriter.close();
                  }
                  if (rs != null) {
                      rs.close();
                  }
                  ps.close();
              }
          }
      }
docs: Write a prj file according a given SRID code.
  @param connection database connection
  @param srid srid code
  @param fileName path of the prj file
  @throws SQLException
  @throws FileNotFoundException