Item.java

import java.util.*;
import java.io.*;

class ItemSorterByPrice implements Comparator<Item> {
    public int compare(Item i1, Item i2){
        return Double.compare(i1.getPrice(), i2.getPrice());
    }
}

public class Item implements Comparable<Item> {
    private String name;
    private double price;

    public Item(String name, double price){
        setName(name);
        setPrice(price);
    }
    public Item(Item item){
        setName(item.getName());
        setPrice(item.getPrice());
    }

    public int compareTo(Item item){
        int temp = this.name.compareTo(item.name);
        if (temp == 0){
            return Double.compare(this.price, item.price);
        } else
            return temp;
    }
    private void setName(String name){
        this.name = name;
    }
    public String getName(){
        return name;
    }

    public void setPrice(double price){
        if (price >= 0)
            this.price = price;
        else
            throw new IllegalArgumentException("Price cannot be negative");
    }
    public double getPrice(){
        return price;
    }

    public String toString(){
        return getName() + " @ " + getPrice();
    }
    /*
    public static void main(String [] args){
        ArrayList<Item> list = new ArrayList<>();

        Item item1 = new Item("saldainis", 1.1);
        Item item2 = new Item("saldainis", 2.1);
        Item item3 = new Item("sultys", 3.1);
        Item item4 = new Item("saldainis", 4.1);

        list.add(item4);
        list.add(item3);
        list.add(item2);
        list.add(item2);
        list.add(item1);
        list.add(item1);
        list.add(item3);
        list.add(item1);

        Collections.sort(list, new ItemSorterByPrice());

        for(int i = 0; i < list.size(); ++i){
            System.out.println(list.get(i));
        }
    }
    */
}