Some comparisons between Java O-O and F# O-O

AbstractClass.fsx

[<AbstractClass>]
type Vehicle() =

    member val Color = Unknown with get, set
    member val Position = {longitude = 0.0; latitude = 0.0} with get, set
    member val Speed = 0.0 with get, set

    member this.Accelerate increment =
        // your logic goes here
        this.Speed <- this.Speed + increment
        this.Speed

AbstractClass.java

public abstract class Vehicle {
	private Color color;
	private Position position;
	private double speed;
	
	public Color getColor() {
		return color;
	}
	public void setColor(Color color) {
		this.color = color;
	}
	public Position getPosition() {
		return position;
	}
	public void setPosition(Position position) {
		this.position = position;
	}
	public double getSpeed() {
		return speed;
	}
	public void setSpeed(double speed) {
		this.speed = speed;
	}
	
	public Vehicle()
	{
		this.setColor(Color.UNKNOWN);
		this.setPosition(new Position(0, 0));
	}
	
	public double Accelerate(double increment) {
		// your logic here
		this.setSpeed(this.getSpeed() + increment);
		return this.getSpeed();
	}
}

EnumAndImmutableClass.java

public enum Color { UNKNOWN, RED, WHITE, BLACK, SILVER }

public final class Position {
	public final double longitude;
	public final double latitude;
	
	public Position(double longitude, double latitude) {
		this.longitude = longitude;
		this.latitude = latitude;
	}
}

EnumAndImmutableTypes.fsx

type Color = Unknown | Red | White | Black | Silver

// A record: a simple immutable properties-only object
type Position = { longitude : float; latitude : double }

InheritedClass.fsx

type Car(brand, color) =
    inherit Vehicle()

    do 
        base.Color <- color

    member val Brand : string = brand with get

    member this.PullHandBrake() =
        // your logic goes here
        this.Accelerate -this.Speed

InheritedClass.java

public class Car extends Vehicle {
	private final String brand;
	
	public String getBrand() {
		return brand;
	}

	public Car(String brand, Color color) {
		super();
		this.brand = brand;
		this.setColor(color);
	}
	
	public double PullHandBrake() {
		// your logic goes here
		return this.Accelerate(-this.getSpeed());
	}
}