this Keyword Practice Test

What problem does this solve in the provided Rectangle class definition?

class Rectangle {

    private int length;

    private int width;

    public Rectangle(int length, int width) {

        this.length = length;

        this.width = width;

        this.printArea();

    }

    public void printArea() {

        System.out.println(this.length * this.width);

    }

}

In the code snippet below, what problem does 'this' solve in the provided class definition?

class Rectangle {

    private int length;

    private int width;

    public Rectangle(int length, int width) {

        // 'this' distinguishes instance variables from parameters

        this.length = length;

        this.width = width;

    }

    public int area() {

        // method call on the current object

        return this.computeArea();

    }

    private int computeArea() {

        return length * width;

    }

}