Java inheritance method with return type

Is it correct to write such a course? The problem is the method getprice () in the item class Each item needs a getprice() But I can't actually reply to something So I fired this Getprice(), get the price of productitem Is there a stronger / better design solution?

class Item {
    String description;

    public Item(String description) {
        this.description = description;
    }

    double getPrice(){return this.getPrice();} //TODO Correct like this?
}

class ProductItem extends Item {
    int amount;
    double pricePerUnit;

    public ProductItem(String description,int amount,double pricePerUnit)         {
        super(description);
        this.amount = amount;
        this.pricePerUnit = pricePerUnit;
    }

    @Override
    double getPrice(){
        return amount * pricePerUnit;
    }
}

Solution

It sounds like item should be an abstract class, and getprice () is an abstract method:

public abstract class Item {
    private final String description;

    public Item(String description) {
        this.description = description;
    }

    public abstract double getPrice();

    public String getDescription() {
        return description;
    }
}

That means you won't be able to write

Item item = new Item("foo"); // Invalid,because Item is abstract

But you can write this:

Item item = new ProductItem("foo",10,2.0);
double p = item.getPrice(); // 20.0

Each concrete (non Abstract) subclass you declare must override getprice () and provide an implementation

For details, see abstract classes and methods section of the java tutorial