# Consider the elevator class as defined below public

• Notes
• UltraLightningCobra8457
• 30

This preview shows page 13 - 20 out of 30 pages.

18) Consider the Elevator class as defined below: public class Elevator { private int numFloors; private int currentFloor; public Elevator(int height) { numFloors = height; currentFloor = 0; } public void moveUp() { if (currentFloor < numFloors - 1) { currentFloor++; } } public String toString() { return "[" + currentFloor + "]"; } } What output would be produced by the following code that creates two Elevator objects? Elevator e1, e2; e1 = new Elevator(5); e2 = new Elevator(2); e1.moveUp(); e1.moveUp(); e1.moveUp(); e2.moveUp(); e2.moveUp(); e2.moveUp(); System.out.println(e1 + " " + e2); (a) [3] [3] (b) [3] [1] (c) [3] [2] (d) [0] [0] (e) [5] [2]

Subscribe to view the full document.

VERSION 00000001 - 14 - COMPSCI 101 CONTINUED 19) What is the output of the following code? Point[] pts = new Point[3]; pts[0] = new Point(100, 200); pts[1] = new Point(300, 400); pts[2] = new Point(500, 600); Point temp = pts[1]; pts[1] = pts[0]; pts[2].x = pts[1].y; pts[1].x = pts[0].y; pts[0] = temp; System.out.println(pts[0].x + " , " + pts[0].y); System.out.println(pts[1].x + " , " + pts[1].y); System.out.println(pts[2].x + " , " + pts[2].y);
VERSION 00000001 - 15 - COMPSCI 101 CONTINUED 20) The following program creates a Timer object and draws a circle on the window. import java.awt.*; import java.awt.event.*; import javax.swing.*; public class MyJPanel extends JPanel implements ActionListener { private Timer t; private Point pos; private int xSpeed, ySpeed; public MyJPanel() { t = new Timer(25, this); t.start(); pos = new Point(100, 100); xSpeed = -4; ySpeed = 4; } public void actionPerformed(ActionEvent e) { pos.x = pos.x + xSpeed; pos.y = pos.y + ySpeed; repaint(); } public void paintComponent(Graphics g){ super.paintComponent(g); g.fillOval(pos.x-25, pos.y-25, 50, 50); } } Which direction would the circle start to move in when this program is executed?

Subscribe to view the full document.

VERSION 00000001 - 16 - COMPSCI 101 QUESTION/ANSWER SHEET FOLLOWS THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.
VERSION 00000001 - 17 - COMPSCI 101 Question/Answer Sheet ID ……….………… CONTINUED THE UNIVERSITY OF AUCKLAND FIRST SEMESTER, 2011 Campus: City Computer Science Principles of Programming (Time Allowed: TWO HOURS) SECTION B Question/Answer Booklet Answer all questions in this section in the space provided. If you run out of space then please use the Overflow Sheet and indicate in the allotted space that you have used the Overflow Sheet. Surname: First Name(s): Student ID: Login Name (UPI): MARKERS ONLY Q1-20 (/40) Q21 (/20) Q22 (/14) Q23 (/8) Q24 (/8) Q25 (/10) TOTAL (/100)

Subscribe to view the full document.

VERSION 00000001 - 18 - COMPSCI 101 Question/Answer Sheet ID ……….………… CONTINUED Question 21 [20 marks] a) Complete the code by making TWO calls to the isCorrect() method so that the output produced by the program is: 1. true 2. false public class Exam { public void start() { boolean result1 = isCorrect(4, 2, 6); //any numbers where the first //two add up to the third System.out.println("1. " + result1); boolean result2 = isCorrect(4, 2, 5); //any numbers where the first //two do not add up to the third System.out.println("2. " + result2); } private boolean isCorrect(int n1, int n2, int result) { int sum = n1 + n2; if (sum == result) { return true; } return false; } } (4 marks)
VERSION 00000001 - 19 - COMPSCI 101

Subscribe to view the full document.

You've reached the end of this preview.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern