//Unable to get the value of an object in hashmap after overriding its hashcode
//This is the item class where i generate hascode based on the item name
public class Item {
private String name;
private Long id;
private double price;
//Constructor
public Item(String name, Long id, double price) {
this.name = name;
this.id = id;
this.price = price;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
//Generating hashcode based on name comparing if item id are //same
@Override
public int hashCode() {
return name.hashCode();
}
@Override
public boolean equals(Object obj) {
return ((Item) obj).id ==(id);
}
@Override
public String toString() {
return "Item {" +
" name='" + name + '\'' +
", id=" + id +
", price=" + price +
'}';
}
//Here there are items but when i pass the exact same item with exact //credentials i get null while checking how many items are there using Hashmap.
public class Warehouse {
Map<Item, Integer> itemList = new HashMap<>();
List<Drone> drones = new ArrayList<>();
private Drone drone;
private String sourceAddress;
private Address address;
public Warehouse(Address address) {
this.address = address;
Item item = new Item("PlayStation 4 pro", (long) 100, 42000);
Item item1 = new Item("X box one S", (long) 200, 40000);
Item item2 = new Item("Apple Macbook Pro", (long) 500, 82000);
Item item3 = new Item("Dell Xps Laptop", (long) 1000, 92000);
Item item4 = new Item("iPhone 7 plus", (long) 2000, 72000);
itemList.put(item, 10);
itemList.put(item1, 20);
itemList.put(item2, 40);
itemList.put(item3, 50);
itemList.put(item4, 20);
}
public Drone getDrone() {
return new Drone();
}
public void setDrone(Drone drone) {
this.drone = drone;
System.out.println("Drone # " + drone.getDroneID() + " has arrived at the warehouse " + address);
}
public Address getAddress() {
return address;
}
public ArrayList<Item> getItemList() {
return (ArrayList<Item>) itemList;
}
//Setting the item
public void setItem(Item item) {
Integer num = itemList.get(item);
if (num == null) {
num = 0;
}
this.itemList.put(item, ++num);
}
//This is where i'm facing the issue, if i query the hashmap for the same item it returns me null, Item even returns the same hashcode
public Item removeItem(Item item) {
Integer num = itemList.get(item);
//## Issue is i get null in num
if(null!= num||num!=0 ){
itemList.put(item,num-1);
}
System.out.println(item);
return item;
}
}