Письменный набор результатов в CSV

Question

Я пытаюсь написать ResultSet в файл CSV, используя следующий код,

public static String getstaffid(String var_1, Connection connection, 
     FileWriter fw) throws SQLException, Exception 
// Create a statement 
{ 
    String record = null; 
    ResultSet rs = null; 
    Statement stmt = connection.createStatement(); 
    boolean empty = true; 
    try { 
     rs = stmt 
       .executeQuery("select username, firstname, lastname, middlename, street, city, stateorprovince, ziporpostalcode, countryorregion, fax, phone, extension, mobile, pager, title, primaryemail, secondaryemail, officename, description, comments, suspendeddate, userdata, employeeid, createuser, updateuser, createdate, updatedate, employeetype, servicedeskticketnumber, startdate, enddate, manager, businessapprover, technicalapprover, delegate, location, jobcodes, customproperty1, customproperty2, customproperty3, customproperty4, customproperty5, customproperty6, customproperty7, customproperty8, customproperty9, customproperty10 from globalusers where username = '"+ var_1 + "'"); 
     ResultSetMetaData metaData = rs.getMetaData(); 
     int columns = metaData.getColumnCount(); 


      while (rs.next()) { 
      empty = false; 
      record = rs.getString(1) + " " + rs.getString(2) + " " + rs.getString(3) + " " + rs.getString(4) + " " + rs.getString(5) + " " + rs.getString(6) + " " + rs.getString(7) + " " + rs.getString(8) + " " + rs.getString(9) + " " + rs.getString(10) + " " + rs.getString(11) + " " + rs.getString(12) + " " + rs.getString(13) + " " + rs.getString(14) + " " + rs.getString(15) + " " + rs.getString(16) + " " + rs.getString(17) + " " + rs.getString(18) + " " + rs.getString(19) + " " + rs.getString(20) + " " + rs.getString(21) + " " + rs.getString(22) + " " + rs.getString(23) + " " + rs.getString(24) + " " + rs.getString(25) + " " + rs.getString(26) + " " + rs.getString(27) + " " + rs.getString(28) + " " + rs.getString(29) + " " + rs.getString(30) + " " + rs.getString(31) + " " + rs.getString(32) + " " + rs.getString(33) + " " + rs.getString(34) + " " + rs.getString(35) + " " + rs.getString(36) + " " + rs.getString(37) + " " + rs.getString(38) + " " + rs.getString(39) + " " + rs.getString(40) + " " + rs.getString(41) + " " + rs.getString(42) + " " + rs.getString(43) + " " + rs.getString(44) + " " + rs.getString(45) + " " + rs.getString(46) + " " + rs.getString(47); 
      fw.append(rs.getString(1)); 
      fw.append(','); 
      fw.append(rs.getString(2)); 
      fw.append(','); 
      fw.append(rs.getString(3)); 
      fw.append('\n'); 
      } 
      System.out.println(record); 
     } 
     finally { 
     fw.flush(); 
     rs.close(); 
     stmt.close(); 
    } 

    return record; 
} 

Это отлично работает. Но для получения строковой записи мне пришлось написать что-то вроде record = rs.getString (1) + "" + ........ + "" + rs.getString (47). Если, например, сказать завтра, если запрос запроса для большего количества атрибутов, я должен добавить больше rs.getString (48) и так далее.

Так я написал функцию как ниже,

for (int i = 1; i <= columns; i++) { 
       record = rs.getString(i) + " "; 
        } 

где значение столбцов,

ResultSetMetaData metaData = rs.getMetaData(); 
    int columns = metaData.getColumnCount(); 

Но теперь я просто получить

нуля нуля . . . null.

Также вместо добавления fw.append (rs.getString (1)) ..... fw.append (rs.getSting (n)), есть ли небольшая функция, которую я могу написать, чтобы не добавлять больше этих добавить.

Большое спасибо

Answer 1

Исправлено. Благодарю. Для кого-то, кто мог привыкнуть с ним, прилагает код

public static String getstaffid(String var_1, Connection connection, 
     FileWriter fw) throws SQLException, Exception 
// Create a statement 
{ 
    String record = null; 
    ResultSet rs = null; 
    Statement stmt = connection.createStatement(); 
    boolean empty = true; 
    try { 
      rs = stmt 
       .executeQuery("select username, firstname, lastname, middlename, street, city, stateorprovince, ziporpostalcode, countryorregion, fax, phone, extension, mobile, pager, title, primaryemail, secondaryemail, officename, description, comments, suspendeddate, userdata, employeeid, createuser, updateuser, createdate, updatedate, employeetype, servicedeskticketnumber, startdate, enddate, manager, businessapprover, technicalapprover, delegate, location, jobcodes, customproperty1, customproperty2, customproperty3, customproperty4, customproperty5, customproperty6, customproperty7, customproperty8, customproperty9, customproperty10 from globalusers where username = '"+ var_1 + "'"); 
      ResultSetMetaData metaData = rs.getMetaData(); 
      int columns = metaData.getColumnCount(); 


      while (rs.next()) 
      { 
       empty = false; 
       for (int i = 1; i <= columns; i++) 
       { 
       record = rs.getString(i); 
       fw.append(rs.getString(i)); 
       fw.append(','); 
       } 
       fw.append('\n'); 

      } 
     } 
     finally 
     { 
      fw.flush(); 
      rs.close(); 
      stmt.close(); 
     } 

    return record; 
}