Composition in Java

package anote;

public class Main {
    public static void main(String[] args) {
        Dimensions dimensions = new Dimensions(20, 20, 7);
        Case theCase = new Case("220B", "Samsung", "240", dimensions);
        Monitor theMonitor = new Monitor("27inch ", "LG", 27, new Resolution(2540, 1440));
        Motherboard theMotherboard = new Motherboard("BJ-200", "Samsung", 4, 6, "v2.44");

        PC thePC = new PC(theCase, theMonitor, theMotherboard);
        thePC.powerUp();
        // So, the PC has a monitor, a motherboard, and a case.
    }
}

class PC {

    private Case theCase;
    private Monitor monitor;
    private Motherboard motherboard;

    public PC(Case theCase, Monitor monitor, Motherboard motherboard) {
        this.theCase = theCase;
        this.monitor = monitor;
        this.motherboard = motherboard;
    }

    public void powerUp() {
        theCase.pressPowerButton();
        drawLogo();
    }

    private void drawLogo() {
        monitor.drawPixelAt(1000, 50, "red");
    }
}

class Monitor {
    // Monitor has a Resolution
    private String model;
    private String manufacturer;
    private int size;
    private Resolution nativaResolution;

    public String getModel() {
        return this.model;
    }

    public String getManufacturer() {
        return this.manufacturer;
    }

    public int getSize() {
        return this.size;
    }

    public Resolution getNativaResolution() {
        return this.nativaResolution;
    }

    public Monitor(String model, String manufacturer, int size, Resolution nativaResolution) {
        this.model = model;
        this.manufacturer = manufacturer;
        this.size = size;
        this.nativaResolution = nativaResolution;
    }

    public void drawPixelAt(int x, int y, String color) {
        System.out.println("Drawing pixel at " + x + "," + y + " in color " + color);
    }
}

class Motherboard {
    private String model;
    private String manufacturer;
    private int ramSlots;
    private int cardSlots;
    private String bios;

    public void loadProgram(String programName) {
        System.out.println("Program " + programName + " is now loading...");
    }

    public String getModel() {
        return this.model;
    }

    public String getManufacturer() {
        return this.manufacturer;
    }

    public int getRamSlots() {
        return this.ramSlots;
    }

    public int getCardSlots() {
        return this.cardSlots;
    }

    public String getBios() {
        return this.bios;
    }

    public Motherboard(String model, String manufacturer, int ramSlots, int cardSlots, String bios) {
        this.model = model;
        this.manufacturer = manufacturer;
        this.ramSlots = ramSlots;
        this.cardSlots = cardSlots;
        this.bios = bios;
    }
}

class Case {
    // Case has a dimensions
    private String model;
    private String manufacturer;
    private String powerSupply;
    private Dimensions dimensions;

    public Case(String model, String manufacturer, String powerSupply, Dimensions dimensions) {
        this.model = model;
        this.manufacturer = manufacturer;
        this.powerSupply = powerSupply;
        this.dimensions = dimensions;
    }

    public void pressPowerButton() {
        System.out.println("Power button pressed");
    }

    public String getModel() {
        return model;
    }

    public String getManufacturer() {
        return manufacturer;
    }

    public String getPowerSupply() {
        return powerSupply;
    }

    public Dimensions getDimensions() {
        return dimensions;
    }

}

class Dimensions {

    private int width;
    private int height;
    private int depth;

    public Dimensions(int width, int height, int depth) {
        this.width = width;
        this.height = height;
        this.depth = depth;
    }

    public int getWidth() {
        return width;
    }

    public int getHeight() {
        return height;
    }

    public int getDepth() {
        return depth;
    }
}

class Resolution {

    private int width;
    private int height;

    public int getWidth() {
        return this.width;
    }

    public void setWidth(int width) {
        this.width = width;
    }

    public int getHeight() {
        return this.height;
    }

    public void setHeight(int height) {
        this.height = height;
    }

    public Resolution(int width, int height) {
        this.width = width;
        this.height = height;
    }
}