try {
    String req = "INSERT INTO nouvelle_installation" +
      "values('" + ref + "','" + today + "','" + check + "','" + nbligne +
      "','" + tligne + "','" + categorie + "','" + instal + "','" + cin +
      "','" + user + "','" + prenom+"','" + numC + "','" + num + "','" + voie +
      "','" + tvoie + "','" + imm + "','" + app + "','" + etage +
      "','" + codep + "')"; 
    Statement m = s.getCon().createStatement();  
    m.executeUpdate(req);
} catch (SQLException e1) {
    e1.printStackTrace();
}
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Erreur de syntaxe près de ''aaa','2012-04-10',' ','-----','------- --------','-------', 'Nouvelle Installati' à la ligne 1