Model

package binh.dev.data.model;

import binh.dev.data.dao.DatabaseDao;
import java.sql.Timestamp;

public class Order {

    private int id;
    private String code;
    private String status;
    private int userId;
    private Timestamp createdAt;

    public static final String PENDING = "pending";
    public static final String FINISHED = "finish";

    public Order(String code, String status, int userId) {
        super();
        this.code = code;
        this.status = status;
        this.userId = userId;
    }

    public Order(int id, String code, String status, int userId, Timestamp createdAt) {
        super();
        this.id = id;
        this.code = code;
        this.status = status;
        this.userId = userId;
        this.createdAt = createdAt;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public int getUserId() {
        return userId;
    }

    public void setUserId(int userId) {
        this.userId = userId;
    }

    public Timestamp getCreatedAt() {
        return createdAt;
    }

    public void setCreatedAt(Timestamp createdAt) {
        this.createdAt = createdAt;
    }
    
    public User getUser(){
        return DatabaseDao.getInstance().getUserDao().find(this.userId);
    }
}

DAO Interface

package binh.dev.data.dao;

import java.util.List;

import binh.dev.data.model.Order;

public interface OrderDao {

    public boolean insert(Order order);

    public boolean update(Order order);

    public boolean delete(int id);

    public Order find(int id);

    public List<Order> findAll();

    public List<Order> findByUser(int userId);

    public Order findByCode(String code);

    public List<Order> findByStatus(String status);
    public int countOrderByDay(String date);

    public double earningOrderByDay(String date);

}

DAO Implement

package binh.dev.data.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.List;
import binh.dev.data.dao.OrderDao;
import binh.dev.data.driver.MySQLDriver;
import binh.dev.data.model.Order;
import java.util.logging.Logger;
import java.util.logging.Level;

public class OrderImpl implements OrderDao {

    Connection con = MySQLDriver.getInstance().getConnection();

    @Override
    public boolean insert(Order order) {
        String sql = "INSERT INTO ORDERS(ID, CODE, STATUS, USER_ID) VALUES(NULL, ?, ?, ?)";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, order.getCode());
            stmt.setString(2, order.getStatus());
            stmt.setInt(3, order.getUserId());

            stmt.execute();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public boolean update(Order order) {
        String sql = "UPDATE ORDERS SET code = ?, status = ?, user_id = ?, created_at = ? WHERE id = ?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, order.getCode());
            stmt.setString(2, order.getStatus());
            stmt.setInt(3, order.getUserId());
            stmt.setTimestamp(4, order.getCreatedAt());
            stmt.setInt(5, order.getId());
            return stmt.execute();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public boolean delete(int id) {
        // TODO Auto-generated method stub
        String sql = "DELETE FROM ORDERS WHERE ID = ?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setInt(1, id);

            return stmt.execute();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return false;
    }

    @Override
    public Order find(int id) {
        String sql = "SELECT * FROM ORDERS WHERE ID = ?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setInt(1, id);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                String code = rs.getString("code");
                String status = rs.getString("status");
                int userId = rs.getInt("user_id");
                Timestamp created_at = rs.getTimestamp("created_at");

                return new Order(id, code, status, userId, created_at);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public List<Order> findAll() {
        // TODO Auto-generated method stub
        List<Order> orders = new ArrayList<>();
        String sql = "SELECT * FROM ORDERS";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);

            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String code = rs.getString("code");
                String status = rs.getString("status");
                int userId = rs.getInt("user_id");
                Timestamp created_at = rs.getTimestamp("created_at");

                orders.add(new Order(id, code, status, userId, created_at));
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return orders;
    }

    @Override
    public List<Order> findByUser(int userId) {
        List<Order> orderList = new ArrayList<>();
        String sql = "SELECT * FROM ORDERS WHERE user_id = ?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setInt(1, userId);

            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String code = rs.getString("code");
                String status = rs.getString("status");
                Timestamp createdAt = rs.getTimestamp("created_at");

                orderList.add(new Order(id, code, status, userId, createdAt));
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return orderList;
    }

    @Override
    public List<Order> findByStatus(String status) {
        List<Order> orderList = new ArrayList<>();
        try {
            String sql = "SELECT * FROM ORDERS WHERE STATUS = ?";
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, status);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String code = rs.getString("code");
                int userId = rs.getInt("user_id");
                Timestamp createdAt = rs.getTimestamp("created_at");
                orderList.add(new Order(id, code, status, userId, createdAt));
            }
        } catch (SQLException ex) {
        }

        return orderList;
    }

    @Override
    public Order findByCode(String code) {
        String sql = "SELECT * FROM ORDERS WHERE CODE= ?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, code);

            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String status = rs.getString("status");
                int userId = rs.getInt("user_id");
                Timestamp createdAt = rs.getTimestamp("created_at");

                return new Order(id, code, status, userId, createdAt);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public int countOrderByDay(String date) {
        int count = 0;
        String sql = "SELECT COUNT(*) AS count FROM orders where date(created_at)=?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, date);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                count = rs.getInt("count");
            }
        } catch (SQLException ex) {
            Logger.getLogger(UserImpl.class.getName()).log(Level.SEVERE, null, ex);
        }
        return count;
    }

    @Override
    public double earningOrderByDay(String date) {
        double total = 0;
        String sql = "SELECT * FROM orders where date(created_at)=?";
        try {
            PreparedStatement stmt = con.prepareStatement(sql);
            stmt.setString(1, date);
            ResultSet rs = stmt.executeQuery();
            while (rs.next()) {
                int id = rs.getInt("id");
                String code = rs.getString("code");
                String status = rs.getString("status");
                int userId = rs.getInt("user_id");
                Timestamp createdAt = rs.getTimestamp("created_at");

                Order order = new Order(id, code, status, userId, createdAt);
//				total += order.getTotal();
            }
        } catch (SQLException ex) {
            Logger.getLogger(UserImpl.class.getName()).log(Level.SEVERE, null, ex);
        }
        return total;
    }

}