What am i missing?

Question about the task

Computer

Java Core, Level 4, Lesson 8

Resolved

The constructors are created, or am i wrong? The parameters are the correct ones?

1. Create the CompItem interface.
2. Add a String getName() method to it.
3. Create Keyboard, Mouse, and Monitor classes that implement the CompItem interface.
4. The getName() method must return the class name. For example, it will return "Keyboard" for the Keyboard class.
5. Create the Computer class.
6. Add a private Keyboard field keyboard to the Computer class.
7. Add a private Mouse field mouse to the Computer class.
8. Add a private Monitor field monitor to the Computer class.
9. Use the Alt+Insert key combination (on Windows) (Constructor command) to create a Computer class constructor with three parameters.
10. Inside the constructor, use the parameters to initialize all three of the class's fields (variables).
11. Create getters for the fields in the Computer (in the class, use the Alt+Insert key combination (on Windows) and select the Getter command).
12. Each class and interface should be in a separate file.

Requirements:

The CompItem interface must be in a separate file.
The CompItem interface must define a getName() method that returns a String and has no parameters.
The Keyboard, Monitor, and Mouse classes must implement the CompItem interface, and be located in separate files.
The getName method in classes implementing the CompItem interface should return a simple class name, e.g. "Keyboard" for the Keyboard class.
The Computer class must be in a separate file and have one private field of each of the following types: Keyboard, Mouse, and Monitor.
The Computer class constructor should have 3 parameters (keyboard, mouse, monitor) and correctly initialize the corresponding fields of the class.
For the Computer class's fields keyboard, mouse, and monitor, you need to create getters (getKeyboard, getMouse, getMonitor) that return the corresponding fields of the Computer class.

package com.codegym.task.task14.task1413; /* Computer */ public class Solution { public static void main(String[] args) { Computer computer = new Computer(new Keyboard(), new Mouse(), new Monitor()); if (isWork(computer.getKeyboard()) && isWork(computer.getMonitor()) && isWork(computer.getMouse())) { System.out.println("Work!"); } } public static boolean isWork(CompItem item) { System.out.println(item.getName()); return item.getName() != null && item.getName().length() > 4; } }

Comments (2)

Popular
New
Old

You must be signed in to leave a comment

Paweł Ż

Level 18 , Warsaw, Poland

3 September 2019, 10:02

Hi, you should initialize the fields (monitor, mouse, keyboard) in constructor, not in getter, and not when you declare variables; For example: declaring fields:

private Monitor monitor;
private Keyboard keyboard;
private Mouse mouse;

constructor should look like this:

public Computer (Keyboard keyboard, Mouse mouse, Monitor monitor) {
this.keyboard = keyboard;
this.mouse = mouse;
this.monitor = monitor;
    }

and finally example of getter:

public Mouse getMouse(){
    return this.mouse;
}

ddi

Level 18 , Dortmund, Germany

3 September 2019, 10:43

Thanks, after a couple of hours i have understand the failure!