Question 1

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

Accepted Answer

The paintComponent method is intended for Swing components, while the paint method is used for other AWT components. It is recommended to override the paintComponent method for Swing components to ensure proper rendering and performance. However, for JApplet and JFrame, it is recommended to override the paint method instead.

Question 2

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

Accepted Answer

The answer of Whenever you need a component of any...

Question 3

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

Accepted Answer

Some browsers may not have the necessary Java Virtual Machine (JVM) installed or may not support the Swing classes used in creating Java applets. This can result in issues with running or displaying applets on those browsers.

Question 4

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

Accepted Answer

The Timer is set to trigger every 500 milliseconds, which is equivalent to 0.5 seconds. Therefore, the event will be generated 2 times per second (1/0.5 = 2).

Question 5

The browser creates an instance of the applet class automatically.

Accepted Answer

When the browser encounters an applet tag in an HTML page, it automatically creates an instance of the applet class and initializes the applet.

Question 6

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

Accepted Answer

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

Question 7

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

Accepted Answer

Applets can be downloaded and executed from the client's computer without being on a Web server, as long as they have the necessary Java Virtual Machine (JVM) installed.

Question 8

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

Accepted Answer

The getDocumentBase() method returns a URL object containing the location of the HTML file that invoked the applet. Therefore, in the given code, getDocumentBase() would return the location of the HTML file, and "mysound.wav" would be appended to the end of that URL to obtain the location of the sound file.

Question 9

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.

Accepted Answer

HTML is primarily used for creating the structure and content of a webpage, but cannot execute advanced functionalities like math calculations or user interaction. This is usually done with other technologies such as JavaScript or server-side languages like PHP.

Question 10

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");

Accepted Answer

The getAudioClip() method does indeed return an object that loads the sound file and assigns its location to the "clip" variable, allowing it to be used to call methods that play the sound file.

Question 11

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

Accepted Answer

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

Question 12

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.

Accepted Answer

The play method loads and plays a sound file once, while the getAudioClip method loads the sound file and may assign its location to a variable so it can be invoked multiple times.

Question 13

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

Accepted Answer

While using Swing components can help improve application functionality and aesthetics, it does not guarantee compatibility with all Java-enabled browsers. Different browsers may have different levels of support for Swing components, and it is always recommended to thoroughly test applets on different browsers to ensure compatibility.

Question 14

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

Accepted Answer

The Applet class does not require a constructor because it is typically initialized using the init() method rather than a constructor.

Quiz 14: Applets and More

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

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

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

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

The browser creates an instance of the applet class automatically.

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

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

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

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.

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");

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

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.

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

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