Solution to 0f05: Coloured points
See code at solutions/code/tutorialquestions/question0f05
Inspect the sample solution carefully and check you understand it. Note that in the
constructor of ColouredPoint, super(coordX, coordY, coordZ) is used to invoke
the constructor of Point, after which this.colour = colour
assigns to the additional colour field. This pattern of building subclass
constructors is standard.
Look at the toString method in ColouredPoint. Observe that
@Override has been used to indicate that this should override a superclass
method. If we accidentally mis-spelled toString, thus not overriding
the parent method, the use of @Override would generate a useful compiler error.
Look at the way super.toString() is used in the body of toString().