jdbc

import java.sql.*;

public class App {
    private Connection c;

    public App() {
        try {
            Class.forName("org.postgresql.Driver");
            System.out.println("carregou");
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        }
    }

    public void setConnection() throws SQLException {
        String host = "https://database-1.cceebyyef1n1.us-east-1.rds.amazonaws.com/";
        String db = "bd_aula";
        String url = "jdbc:postgresql://" + host + "/" + db;
        String user = "aluno";
        String senha = "aluno";
        c = DriverManager.getConnection(url, user, senha);
    }

    public void executarConsulta() throws SQLException {
        Statement st = c.createStatement();
        String sql = "SELECT * FROM universidade.professor";
        ResultSet rs = st.executeQuery(sql);
        while (rs.next()) {
            System.out.println(rs.getRow() + " ");
            String col1 = rs.getString(1);
            String col2 = rs.getString(2);
            String data = rs.getString("data_nascimento");
            System.out.println(col1 + "\t" + col2 + "\t" + data);

        }
    }

    public static void main(String[] args) {
        App t = new App();
        try {
            t.setConnection();
            System.out.println("conexão ok...");
            t.executarConsulta();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

}