interface or abstract class when making two seperate java beans

Question

I have two types of materials for my web project, where I want to make orders of garages for users.

So far I have one class:

public class OrderLine {

private int materialId;
private String name;
private int length;
private int amount;
private String description;
private int price;
private int materialgroup;

public OrderLine(int materialId, String name, int length, int amount, String description, int price, int materialgroup) {
    this.materialId = materialId;
    this.name = name;
    this.length = length;
    this.amount = amount;
    this.description = description;
    this.price = price;
    this.materialgroup = materialgroup;
}

public int getMaterialId() {
    return materialId;
}

public void setMaterialId(int materialId) {
    this.materialId = materialId;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public int getLength() {
    return length;
}

public void setLength(int length) {
    this.length = length;
}

public int getAmount() {
    return amount;
}

public void setAmount(int amount) {
    this.amount = amount;
}

public String getDescription() {
    return description;
}

public void setDescription(String description) {
    this.description = description;
}

public int getPrice() {
    return price;
}

public void setPrice(int price) {
    this.price = price;
}

public int getMaterialgroup() {
    return materialgroup;
}

public void setMaterialgroup(int materialgroup) {
    this.materialgroup = materialgroup;
}

@Override
public String toString() {
    return name + "" + length + "" + amount + "" + description;
}

}

So far this is only a java bean because I have all my calculation method in a separate class. But I want to make two different classes one with and one without amount, how can I do this the easiest way

Answer 1

You can just use java inheritance

class Super {
   int a;
}
class Sub extends Super {
  int b; 
}

Sub will inherit all the attributes and methods of Super.