I have the following class: public abstract class Map { protected PriorityQueue openNodes; } My implementation currently work like this: public Map() { PriorityQueue<Node&…
Tag: oop
How to use class type of method parameter?
I have the following classes: Foo1 extends Bar and Foo2 extends Bar I would like to pass the type of either Foo1, or Foo2 in my method to create either a Foo1, or a Foo2, like this: Is there any approach to achieve this? Answer You can have some flexibility using generics, by declaring: With this all the foll…
What is a good way to implement calculations for extended classes?
I have the following classes: I would like to create a method like Where I only pass in the nodes, and the logic in either the method, or the nodes, or the map recognizes what kind of map I’m using. My current solution looks like this: When I look at this code, I think there has to be a better
Difference between CustomTextView as Parent and Textview as Parent
i created CustomTextview as below . what is the difference between This and this When i put this TextView textView = findViewbyId(R.id.view); IDE runs without throwing error. Why? Thanks! Answer A real life comparison: When you learn to drive a manual transmission car, you can drive almost any manual transmis…
How to create a ‘best fit’ comparison of several integers and an input integer in Java?
I have 3 (subject to change to more rooms in the future, but that’s irrelevant) rooms, all with a different number of seats (suppose these are ‘Room’ Objects): Room Seats 1 10 2 20 3 30 I then input a value of the number of seats I need to reserve and then my code will automatically assign t…
Java – violation of Liskov substitution principle?
I have the following code: interface Ops{ void remove(); } interface BeforeRemove{ void doBeforeRemove(); } class A implements Ops{ @Override public void remove() { System….
How would I make a new fraction if a fraction cannot be simplified?
So I’m writing an assignment for my OOP class that asks the user for a number of fractions, then randomly generates that number of fractions. Part of the assignment states that if one of the fractions cannot be simplified then skip it and create a new fraction that can be simplified. However the unreduc…
is there a preferable relationship between classes? Why? [closed]
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 2 years ago. Improve this question is there really a preferable relationship between classes ? or it depends …
How to call the method of the subclass using method of Parent class?
I have a Shape method that has two arguments first is the width and the second is the height. I have two subclasses, one is the rectangle and another is triangle. I want to call the area() the method defined in both triangle and rectangle with the help of the area() of the Shape class. I have written this pie…
using spring dependency injection for runtime generated dependencies
I am new to Spring and to better understand what I’m learning, I decide to integrate Spring into one of my projects. In the project, a collection of Events is generated at runtime, where Event is a POJO. FetcherA and FetcherB are two classes that depended on an Event instance to fetch their output, whic…