Unit test DAO classes with JUnit using a Connection Pool

Hi everyone i'm new here and i need your help to unit test with junit a DAO class with a connection pool. This is the ConPool:

public class ConPool {

private static DataSource datasource;

/**
 * {@return} Connection
 * {@throws} SQLException
 *     Ritorna la connessione al db.
 */

public static Connection getConnection() throws SQLException {
if (datasource == null) {
  PoolProperties p = new PoolProperties();
  p.setUrl("jdbc:mysql://localhost:3306/GameLand?serverTimezone="
          + TimeZone.getDefault().getID());
  p.setDriverClassName("com.mysql.cj.jdbc.Driver");
  p.setUsername("root");
  p.setPassword("basedidati");
  p.setMaxActive(100);
  p.setInitialSize(10);
  p.setMinIdle(10);
  p.setRemoveAbandonedTimeout(60);
  p.setRemoveAbandoned(true);
  datasource = new DataSource();
  datasource.setPoolProperties(p);
}
  return datasource.getConnection();
 }
}

and this is the DAO class that i want to test:

public class OrdineDAO {
/**
 * {@return} ArrayList of Ordine.
 */

public synchronized ArrayList<Ordine> doRetrieveAll() {

String query = "SELECT * FROM ordine";
ArrayList<Ordine> result = new ArrayList<Ordine>();

try (Connection conn = ConPool.getConnection()) {

  PreparedStatement ps = conn.prepareStatement(query);
  ResultSet rs = ps.executeQuery();
  while (rs.next()) {

    Ordine ord = new Ordine();
    ord.setConsegnato(rs.getBoolean("consegnato"));
    ord.setDataOra(rs.getString("dataOra"));
    ord.setIdOrdine(rs.getInt("idOrdine"));
    ord.setIdProdotto(rs.getInt("idProdotto"));
    ord.setPrezzoFis(rs.getDouble("prezzoFis"));
    ord.setPrezzoDig(rs.getDouble("prezzoDig"));
    ord.setIva(rs.getDouble("iva"));
    ord.setQuantitaDigitale(rs.getInt("quantitaDigitale"));
    ord.setQuantitaFisico(rs.getInt("quantitaFisico"));
    ord.setIdUtente(rs.getInt("idUtente"));
    result.add(ord);

  }

} catch (SQLException e) {

  e.printStackTrace();

}


return result;
}
/**
 * {@param} id: int.
 * {@return} ArrayList of Ordine.
 */

public synchronized ArrayList<Ordine> doRetrieveByUser(int id) {

PreparedStatement ps = null;
String query = "SELECT * FROM ordine WHERE idUtente = ?";
ArrayList<Ordine> result = new ArrayList<Ordine>();

try (Connection conn = ConPool.getConnection()) {

  ps = conn.prepareStatement(query);
  ps.setInt(1, id);
  ResultSet rs = ps.executeQuery();
  while (rs.next()) {

    Ordine ord = new Ordine();
    ord.setConsegnato(rs.getBoolean("consegnato"));
    ord.setDataOra(rs.getString("dataOra"));
    ord.setIdOrdine(rs.getInt("idOrdine"));
    ord.setIdProdotto(rs.getInt("idProdotto"));
    ord.setPrezzoFis(rs.getDouble("prezzoFis"));
    ord.setPrezzoDig(rs.getDouble("prezzoDig"));
    ord.setIva(rs.getDouble("iva"));
    ord.setQuantitaDigitale(rs.getInt("quantitaDigitale"));
    ord.setQuantitaFisico(rs.getInt("quantitaFisico"));
    ord.setIdUtente(rs.getInt("idUtente"));
    result.add(ord);

  }

} catch (SQLException e) {

  e.printStackTrace();

}

return result;
}
/**
 * {@param} data1: String.
 * {@param} data2: String.
 * {@return} ArrayList of Ordine.
 */

public synchronized ArrayList<Ordine> doRetrieveByDate(String data1, String data2) {

PreparedStatement ps = null;
String query = "SELECT * FROM ordine WHERE dataOra >= ? AND dataOra <= ?";
ArrayList<Ordine> result = new ArrayList<Ordine>();

try (Connection conn = ConPool.getConnection()) {

  ps = conn.prepareStatement(query);
  ps.setString(1, data1);
  ps.setString(2, data2);
  ResultSet rs = ps.executeQuery();
  while (rs.next()) {

    Ordine ord = new Ordine();
    ord.setConsegnato(rs.getBoolean("consegnato"));
    ord.setDataOra(rs.getString("dataOra"));
    ord.setIdOrdine(rs.getInt("idOrdine"));
    ord.setIdProdotto(rs.getInt("idProdotto"));
    ord.setPrezzoFis(rs.getDouble("prezzoFis"));
    ord.setPrezzoDig(rs.getDouble("prezzoDig"));
    ord.setIva(rs.getDouble("iva"));
    ord.setQuantitaDigitale(rs.getInt("quantitaDigitale"));
    ord.setQuantitaFisico(rs.getInt("quantitaFisico"));
    ord.setIdUtente(rs.getInt("idUtente"));
    result.add(ord);

  }

} catch (SQLException e) {

  e.printStackTrace();

}

 return result;
 }

}

starting first with doRetrieveAll method, i tried to do a

@Test
public void doRetrieveAll_Success() throws SQLException {
    assertNotNull(ordineDAO.doRetrieveAll());
}

But i need to know how to set the @BeforeAll in order to test this method. Can you please help me understanding how to set properly the test class? Thank you