Deck 14: Applets and More

Question 1

Applet restrictions are:

A) necessary to prevent malicious code from attacking or spying on unsuspecting users
B) determined by the Web browser
C) optional in Java 7
D) enabled only if the applet is running on a Web server

Answer 1

A

Question 2

________ is the language that Web pages are written in.

A) PHP
B) XML
C) HTML
D) JavaScript

Answer 2

C

Question 3

In the link produced by the following HTML, what word would you click to go to the linked location?
Click here to learn more about
applications.

A) Click
B) here
C) Click here to learn more about
D) applications

Answer 3

D

Question 4

When the applet viewer opens an HTML document with more than one applet tag:

A) it terminates immediately
B) it displays the first applet, and then terminates
C) it displays each applet in a separate window
D) it displays each applet in order in the same window

Question 5

Look at the following applet code:
1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 int[] xCoords = {20, 20, 60, 100, 140, 140, 100, 60};
12 int[] ycoords = {20, 100, 140, 140, 100, 60, 20, 20};
13 super.paint(g);
14 g.setColor(Color.YELLOW);
15 g.fillPolygon(xCoords, yCoords, 8);
16 g.setColor(color.BLACK);
17 g.setFont(new Font("SansSerif", Font.BOLD, 35));
18 g.drawString("SLOW", 35, 95);
19 }
20 }
What is the color of the polygon?

A) White
B) Yellow
C) Black
D) None of the above

Question 6

Which of the following will load the applet, TestApplet?

A)
B)
C)
D)

Question 7

Which of the following is NOT a valid AWT class?

A) Panel
B) Applet
C) TextArea
D) JMenu

Question 8

Which tag will produce largest text?

A)

Hello

B)

Hello

C)

Hello

D)

Hello

Question 9

What does the tag

cause to happen?

A) A double space
B) A paragraph break
C) Indentation for a paragraph
D) Plain text to be displayed

Question 10

When someone visits a Web page containing a Java applet:

A) the applet is executed on the server and displayed on the Web page
B) the applet is downloaded to the visitor's browser and executed
C) the applet is executed using a portion of the resources from each visitor's browser
D) the visitor's browser acts as the server and hosts the applet for other visitors

Question 11

An HTML document is usually saved with what file name extension?

A) )xml
B) )asp
C) )js
D) )html

Question 12

Look at the following applet code:
1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 int[] xCoords = {20, 20, 60, 100, 140, 140, 100, 60};
12 int[] ycoords = {20, 100, 140, 140, 100, 60, 20, 20};
13 super.paint(g);
14 g.setColor(Color.YELLOW);
15 g.fillPolygon(xCoords, yCoords, 8);
16 g.setColor(color.BLACK);
17 g.setFont(new Font("SansSerif", Font.BOLD, 35));
18 g.drawString("SLOW", 35, 95);
19 }
20 }
How many vertices does the polygon have?

A) 5
B) 6
C) 7
D) 8

Question 13

In the following code, which line has an error?
1 public class TestApplet extends JApplet
2 {
3 public void init()
4 {
5 super.JApplet();
6 JLabel label = new JLabel("Test label");
7 setLayout(new FlowLayout());
8 add(label);
9 }
10 }

A) 1
B) 3
C) 5
D) There are no errors

Question 14

Look at the following applet code. 1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 int[] xCoords = {20, 20, 60, 100, 140, 140, 100, 60};
12 int[] ycoords = {20, 100, 140, 140, 100, 60, 20, 20};
13 super.paint(g);
14 g.setColor(Color.YELLOW);
15 g.fillPolygon(xCoords, yCoords, 8);
16 g.setColor(color.BLACK);
17 g.setFont(new Font("SansSerif", Font.BOLD, 35));
18 g.drawString("SLOW", 35, 95);
19 }
20 }
What will be the coordinates of the third point of the polygon?

A) (60, 140)
B) (140, 60)
C) (100, 140)
D) (140, 100)

Question 15

An applet using a Swing GUI extends which class?

A) Applet
B) JApplet
C) JSwing
D) JFrame

Question 16

If a frame component is 200 pixels wide and 300 pixels high, the lower, left-hand corner has (X, Y) coordinates of:

A) (0, 299)
B) (0, 300)
C) (200, 0)
D) (0, 0)

Question 17

Applets are important because the can be used to:

A) extend the capabilities of a web page
B) process large data files
C) run other programs on the user's system
D) convert machine language into HTML

Question 18

In an HTML document, the tags:

A) instruct the Web browser how to format the text
B) instruct the Web browser where to place images
C) instruct the Web browser what to do when the user clicks on a link
D) all of the above

Question 19

Which of the following is NOT a restriction placed on applets?

A) Applets cannot create files on the user's system.
B) Applets cannot execute operating system procedures on the user's system.
C) Applets cannot display a window.
D) Applets cannot retrieve the user's identity.

Question 20

Due to security restrictions, applets cannot:

A) Delete files
B) Read the contents of files
C) Create files on the user's system
D) All of the above

Question 21

These are Java programs that are usually part of a Web site.

A) Applications
B) Applets
C) Classes
D) Web services

Question 22

A mouse motion listener class can respond to:

A) The mouse button is clicked on
B) The mouse cursor exits a component's screen space
C) The mouse moved
D) The mouse button is released

Question 23

If a frame component is 300 pixels wide and 200 pixels high, the upper, right-hand corner has (X, Y) coordinates of:

A) (0, 0)
B) (300, 0)
C) (200, 300)
D) (299, 0)

Question 24

What will happen if you use instead of in an HTML document?

A) The tag will be ignored.
B) The text inside the tag will be centered just the same.
C) The text inside the tag will be centered and appear in all uppercase letters.
D) An exception will be thrown.

Question 25

Look at the following applet code:
1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 super.paint(g);
12 g.setColor(Color.YELLOW);
13 g.fillOval(100, 100, 50, 50);
14 g.setColor(Color.BLACK);
15 g.setFont(new Font("SansSerif", Font.BOLD, 35));
16 g.drawString("SLOW", 110, 110);
17 }
18 }
What shape will the oval have?

A) Oblong, width greater than height
B) Oblong, width less than height
C) Circle
D) Cannot tell

Question 26

An applet using a Swing GUI is extended from this class.

A) JFrame
B) JLabel
C) JSwing
D) JApplet

Question 27

What does the HTML tag

---

cause to happen?

A) A header routine is created.
B) A horizontal line will be displayed.
C) A default header reference will be linked to.
D) The window will be blanked out before the remainder of the text is displayed.

Question 28

To support the Swing classes in applets, some browsers require a ________, which is software that extends or enhances another program.

A) extension
B) plug-in
C) booster
D) widget

Question 29

Look at the following applet code:
1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 super.paint(g);
12 g.setColor(Color.YELLOW);
13 g.fillOval(100, 100, 50, 50);
14 g.setColor(Color.BLACK);
15 g.setFont(new Font("SansSerif", Font.BOLD, 35));
16 g.drawString("SLOW", 110, 110);
17 }
18 }
Which line sets the color that will be used to draw "SLOW"?

A) 7
B) 12
C) 14
D) 16

Question 30

Which of the following can a mouse listener respond to?

A) The mouse button is pressed.
B) The mouse button is clicked.
C) The mouse cursor enters a component's screen space.
D) All of the above

Question 31

When you extend an interface, you must implement all the methods defined in the interface. If you are interested in only one or two mouse events, you can extend the ________ class which implements the MouseListener interface, but does not require you to write all the functions in the interface.

A) MouseAdapter
B) MouseExtender
C) MouseMotionAdapter
D) MouseMotionExtender

Question 32

In an applet, events are handled:

A) with special applet event listeners
B) differently, depending upon which computer is running the applet
C) with event listeners, exactly as they are in GUI applications
D) by always terminating the applet

Question 33

If an applet attempts to violate one of the JVM restrictions:

A) the program has a fatal error.
B) it will display a window stating that it has violated the restriction.
C) an exception is thrown.
D) it automatically notifies the Web server of the violation.

Question 34

Given the following code, how many times per second will the TimerListener event be generated?
Timer timer = new Timer(1000, new TimerListener());

A) 1
B) 10
C) 100
D) 1000

Question 35

Which of the following sound file formats does Java not support?

A) )wav
B) )au
C) )mid
D) Java supports all of the above.

Question 36

One way of viewing the results of the applet which is invoked in the HTML document TestApplet.html is to enter the following at the command prompt.

A) appletviewer TestApplet.html
B) appleviewer TestApplet
C) viewapplet TestApplet.html
D) view TestApplet

Question 37

In the following code that uses a Swing GUI, which line has an error?
1 public class TestApplet extends Applet
2 {
3 public void init()
4 {
5 JLabel label = new JLabel("Test label");
6 setLayout(new FlowLayout());
7 add(label);
8 }
9 }

A) 1
B) 3
C) 5
D) There are no errors.

Question 38

Look at the following applet code:
1 import javax.swing.*;
2 import java.awt.*;
3 public class GraphicsTest extends JApplet
4 {
5 public void init()
6 {
7 getContentPane().setBackground(Color.WHITE);
8 }
9 public void paint(Graphics g)
10 {
11 super.paint(g);
12 g.setColor(Color.YELLOW);
13 g.fillOval(100, 100, 50, 50);
14 g.setColor(Color.BLACK);
15 g.setFont(new Font("SansSerif", Font.BOLD, 35));
16 g.drawString("SLOW", 110, 110);
17 }
18 }
What will be the coordinates of the center of the oval?

A) (100, 100)
B) (50, 50)
C) (100, 50)
D) (125, 125)

Question 39

The ________ object is responsible for drawing the entire applet window.

A) Graphics
B) Applet
C) SuperClass
D) JFrame

Question 40

Hypertext can contain:

A) a Java application program
B) exception methods
C) executable code
D) a link to another Web page

Question 41

For all Swing components EXCEPT JApplet and JFrame, you should override the paintComponent method instead of the paint method.

Question 42

Whenever you need a component of any type to be painted, call the paint method.

Question 43

Some browsers do not directly support the Swing classes of applets.

Question 44

Given the following code, how many times per second will the TimerListener event be generated?
Timer timer = new Timer(500, new TimerListener());

A) 5
B) 50
C) 2
D) 500

Question 45

The browser creates an instance of the applet class automatically.

Question 46

The delay parameter in the Timer constructor is the amount of time between action events, measured in microseconds.

Question 47

An applet does not have to be on a Web server in order to be executed.

Question 48

In the following code, what does getDocumentBase()return?
Play(getDocumentBase(), "mysound.wav");

A) A URL object containing the location of the applet's .class file
B) A URL object containing the location of the HTML file that invoked the applet
C) The HTML location "mysound.wav"
D) The sound file itself

Question 49

HTML describes the content and layout of a Web page, and creates links to other files and Web pages, but does not have sophisticated abilities such as performing math calculations and interacting with the user.

Question 50

The following getAudioClip() method returns an object that will load the sound file and assign the location of that file to clip which can then be used to call methods that may play the sound file one or more times:
Audioclip clip = getAudioClip(getDocumentBase(), "mysound.wav");

Question 51

The delay parameter in the Timer constructor is the amount of time between action events, measured in milliseconds.

Question 52

The play method will load and play a sound file once, then release it for garbage collection. The getAudioClip method will load the sound file and may assign the location of the sound file to a variable so it may be invoked many times.

Question 53

If you want to make sure that an applet is compatible with all Java-enabled browsers, use Swing components instead of AWT.

Question 54

The Applet class requires that you write a constructor to create an object of the class.