Question

 Please implement Sample string toString()method for each class and return itself a string, not the output. 
import java.util.ArrayList;

public class Customer extends User{
    private ArrayList orders;

    public Customer(String display_name, String password, String email) {
        super(display_name, password, email);
    }

    @Override
    public String getPermissionLevel() {
        return "CUSTOMER";
    }

    public void addOrder(Order order){
        this.orders.add(order);
    }

    public ArrayList listOrders(){
        return this.orders;
    };
}

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public class ElectronicProduct extends Product{
    private long SNo;
    private String warranty_period;

    public ElectronicProduct(long SNo, String warranty_period, String productId, String productName, String brandName, String Description) {
        super(productId, productName, brandName, Description);
        this.SNo = SNo;
        this.warranty_period = warranty_period;
    }

}

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public class HomeProduct extends Product{

    String location;
    public HomeProduct(String location, String productId, String productName, String brandName, String Description) {
        super(productId, productName, brandName, Description);
        this.location = location;
    }
}

----------------------

import java.util.ArrayList;
import java.util.Date;
public class Order {
    private int order_no;
    private ArrayList products;
    private String order_Status;
    private Date final_date;

    public Order(int order_no, String order_Status, Date final_date) {
        this.order_no = order_no;
        this.order_Status = order_Status;
        this.final_date = final_date;
        this.products = new ArrayList<>();
    }

    public Date getFinal_date() {
        return final_date;
    }

    public String getOrder_Status() {
        return order_Status;
    }

    public int getOrder_no() {
        return order_no;
    }

    public void setFinal_date(Date final_date) {
        this.final_date = final_date;
    }

    public void setOrder_Status(String order_Status) {
        this.order_Status = order_Status;
    }

    public void setOrder_no(int order_no) {
        this.order_no = order_no;
    }

    public ArrayList getProducts(){
        return this.products;
    }

    public void addProduct(Product product){
        this.products.add(product);
    }

}

------------------------------------------------

import java.time.LocalDate;
import java.util.ArrayList;
import java.util.Date;

public class Product {

    private String productId;
    private String productName;
    private String brandName;
    private String description;
    private ArrayList categories;
    private LocalDate dateCatalog;

    public Product(String productId, String productName, String brandName, String description) {
        this.productId = productId;
        this.productName = productName;
        this.brandName = brandName;
        this.description = description;
        this.dateCatalog = LocalDate.now();
        this.categories = new ArrayList<>();
    }

    public String getProductId() {
        return productId;
    }

    public String getDescription() {
        return description;
    }

    public String getProductName() {
        return productName;
    }

    public void addCategory(Category category){
        this.categories.add(category);
    }

    public ArrayList listCategories(){
        return this.categories;
    }
}

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Answer 1

I have added toString method for each class.

Full Java Code :

import java.util.ArrayList;

public class Customer extends User{

    private ArrayList orders;

    public Customer(String display_name, String password, String email) {

        super(display_name, password, email);

    }

//sample toString method for Customer class

public String toString()

    {

        return "this is toString method of Customer class & " +display_name + " " + password + " " + email;

    }  

    @Override

    public String getPermissionLevel() {

        return "CUSTOMER";

    }

    public void addOrder(Order order){

        this.orders.add(order);

    }

    public ArrayList listOrders(){

        return this.orders;

    };

}

public class ElectronicProduct extends Product{

    private long SNo;

    private String warranty_period;

    public ElectronicProduct(long SNo, String warranty_period, String productId, String productName, String brandName, String Description) {

        super(productId, productName, brandName, Description);

        this.SNo = SNo;

        this.warranty_period = warranty_period;

    }

//tostring method for ElectronicProduct Class

public String toString()

    {

        return productId + " " + productName + " "+ brandName + " " + description + " " +SNo + " " +warranty_period;

    }

}

--------------

public class HomeProduct extends Product{

    String location;

    public HomeProduct(String location, String productId, String productName, String brandName, String Description) {

        super(productId, productName, brandName, Description);

        this.location = location;

    }

//tostring method for HomeProduct Class

public String toString()

    {

        return productId + " " + productName + " "+ brandName + " " + description + " " +location;

    }

}

----------------------

import java.util.ArrayList;

import java.util.Date;

public class Order {

    private int order_no;

    private ArrayList products;

    private String order_Status;

    private Date final_date;

    public Order(int order_no, String order_Status, Date final_date) {

        this.order_no = order_no;

        this.order_Status = order_Status;

        this.final_date = final_date;

        this.products = new ArrayList<>();

    }

//sample toString method for Oder class

public String toString()

    {

        return order_no + " " + products + " " + order_Status + " " + final_date ;

    }

    public Date getFinal_date() {

        return final_date;

    }

    public String getOrder_Status() {

        return order_Status;

    }

    public int getOrder_no() {

        return order_no;

    }

    public void setFinal_date(Date final_date) {

        this.final_date = final_date;

    }

    public void setOrder_Status(String order_Status) {

        this.order_Status = order_Status;

    }

    public void setOrder_no(int order_no) {

        this.order_no = order_no;

    }

    public ArrayList getProducts(){

        return this.products;

    }

    public void addProduct(Product product){

        this.products.add(product);

    }

}

------------------------------------------------

import java.time.LocalDate;

import java.util.ArrayList;

import java.util.Date;

public class Product {

    private String productId;

    private String productName;

    private String brandName;

    private String description;

    private ArrayList categories;

    private LocalDate dateCatalog;

    public Product(String productId, String productName, String brandName, String description) {

        this.productId = productId;

        this.productName = productName;

        this.brandName = brandName;

        this.description = description;

        this.dateCatalog = LocalDate.now();

        this.categories = new ArrayList<>();

    }

//tostring method for Product Class

public String toString()

    {

        return productId + " " + productName + " "+ brandName + " " + description + " " + dateCatalog + " " +categories;

    }

    public String getProductId() {

        return productId;

    }

    public String getDescription() {

        return description;

    }

    public String getProductName() {

        return productName;

    }

    public void addCategory(Category category){

        this.categories.add(category);

    }

    public ArrayList listCategories(){

        return this.categories;

    }

}

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