Row Count in Java JDBC

package com.demo;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Demo {

    public static void main(String[] args) {
        System.out.println("count: " + count());
    }

    private static long count() {
        long result = 0;
        try {
            PreparedStatement preparedStatement = ConnectDB.connection()
                    .prepareStatement("select count(*) from mobile");
            ResultSet resultSet = preparedStatement.executeQuery();
            resultSet.next();
            result = resultSet.getLong(1);
        } catch (Exception e) {
            result = 0;
        } finally {
            ConnectDB.disconnect();
        }
        return result;
    }

    public class ConnectDB {

        private static Connection connection;

        public static Connection connection() {
            try {
                Class.forName("com.mysql.cj.jdbc.Driver");
                connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/your_database", "username",
                        "password");
            } catch (Exception e) {
                e.printStackTrace();
                connection = null;
            }
            return connection;
        }

        public static void disconnect() {
            if (connection != null) {
                try {
                    connection.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
        }

    }

}