这是基于OP提供的内容的初步响应.

This is an initial response based on what little the OP provided.

您不会在派生类中覆盖获取器(并且基本的基本实现无法编译):

You are not overriding your getters in your deriving classes (and the basic implementation in the base can not compile) :

public abstract class Commodity {

    public double getProductionCost() {
       // no return value!
    }

    public double getRetailPrice() {
       // no return value!         
    }
}

public abstract class TimsProduct extends Commodity{
    private String name;
    private double cost;
    private double price;


    public TimsProduct(String name, double cost, double price){
        this.name = name;
        this.cost = cost;
        this.price = price;

    } 

    public String getName(){
        return name;
    }
    // no @Override!
    public double getProductionCost(){
        return cost;
}
    // no @Override!
    public double getRetailPrice(){
        return price;
    }

    public String toString(){
        return ("Name is:  " + name + "cost is: " + cost + "price is: " + price );
    }
}