try

try {
            String sql ="UPDATE murid SET nis = '"+nis.getText()+"', nama = '"+nama.getText()+"', jk = '"+jk.getText()+"', alamat = '"+al.getText()+"', kelas = '"+kelas.getText()+"', jurusan = '"+jurusan.getText()+"', agama = '"+agama.getText()+"', ortu = '"+ortu.getText()+"' WHERE nis = '"+nis.getText()+"'";
            java.sql.Connection con=(Connection)Db_Connection.configDB();
            java.sql.PreparedStatement pst=con.prepareStatement(sql);
            pst.execute();
            JOptionPane.showMessageDialog(this, "data berhasil di edit");
        } catch (Exception e) {
            JOptionPane.showMessageDialog(null, "Perubahan Data Gagal"+e.getMessage());
        }
        TampilData();
        kosong();
    }