MyClass cannot be cast to java.lang.Comparable: java.lang.ClassCastException
- by user2234225
I am doing a java project and I got this problem and don't know how to fix it.
The classes in my project (simplified):
public class Item {
private String itemID;
private Integer price;
public Integer getPrice() {
return this.price;
}
}
public class Store {
private String storeID;
private String address;
}
public class Stock {
private Item item;
private Store store;
private Integer itemCount;
public Integer getInventoryValue() {
return this.item.getPrice() * this.itemCount;
}
}
Then I try to sort an ArrayList of Stock so I create another class called CompareByValue
public class CompareByValue implements Comparator<Stock> {
@Override
public int compare(Stock stock1, Stock stock2) {
return (stock1.getInventoryValue() - stock2.getInventoryValue());
}
}
When I try to run the program, it gives the error:
Exception in thread "main" java.lang.ClassCastException: Stock cannot be cast to java.lang.Comparable
Anyone know what's wrong?
