Question 1

The purpose of the try and catch blocks is to:

Accepted Answer

The try and catch blocks are used to handle exceptions in a program, allowing the code to continue running even if an error occurs.

Question 2

At run time, if a non-integer is entered, the call to the parseInt method will generate a(n):

Accepted Answer

The parseInt method throws a NumberFormatException if the input string cannot be parsed into an integer.

Question 3

Melanie writes some code with the public class EmailChecker. She uses try and catch blocks to catch thrown exceptions. A user enters this email address: Javalovre@sw.com. Which of the following is a likely outcome?

Accepted Answer

The email address "Javalovre@sw.com" does not contain any obvious errors that would cause an exception to be thrown, so the program will likely continue executing inside the try block.

Question 4

What is the advantage of declaring a constant as static?

Accepted Answer

Declaring a constant as static saves memory because the constant is shared across all instances of the class, rather than each instance having its own copy.

Question 5

Which of the following is the exception thrown by void writeObject( Object o )?

Accepted Answer

The answer of Which of the following is the exception...

Question 6

ObjectOutputStream( OutputStream out ) is a:

Accepted Answer

ObjectOutputStream(OutputStream out) is a constructor for the ObjectOutputStream class in Java, which initializes a new ObjectOutputStream that writes to the specified OutputStream.

Question 7

ObjectOutputStream is a:

Accepted Answer

ObjectOutputStream is a class in Java used for writing objects to an OutputStream.

Question 8

What makes an instance variable averageGPA a good candidate for being declared as transient?

Accepted Answer

The value of averageGPA can be recalculated or reproduced from other data, making it unnecessary to serialize and store it.

Question 9

What is a token?

Accepted Answer

A token is an individual piece of data, often used in programming and data processing to represent a single unit of information.

Question 10

Which package, introduced with Java 8, provides support for aggregate sequential and parallel operations on a collection of elements?

Accepted Answer

java.util.stream package provides support for aggregate sequential and parallel operations on a collection of elements.

Question 11

PrintWriter( File f) throws a FileNotFoundException.

Accepted Answer

The PrintWriter constructor that takes a File object as an argument can throw a FileNotFoundException if the file cannot be opened or created.

Question 12

A Stream can easily be constructed from an ArrayList.

Accepted Answer

In Java, you can easily create a Stream from an ArrayList using the `stream()` method, which is available on all Collection types, including ArrayList.

Question 13

Large amounts of data reside in which of the following?

Accepted Answer

Large amounts of data can reside in both data files and databases, as both are used to store and manage data.

Question 14

Which of the following methods in the Exception classes returns void?

Accepted Answer

The method printStackTrace() in the Exception class returns void as it prints the stack trace to the standard error stream.

Question 15

To correct this segment, line 12 should be changed to int n = 1;.
10 public static void main( String [ ] args )
11 {
12 int n;
13 String s = JOptionPane.showInputDialog( null,
14 "Enter an integer" );
15 System.out.println( "You entered " + s );
16
17 try
18 {
19 n = Integer.parseInt( s );
20 System.out.println( "Conversion was successful." );
21 }

Accepted Answer

The segment already declares the variable `int n;` on line 12, and it is assigned a value on line 19. Changing line 12 to `int n = 1;` is unnecessary and would not correct any errors in the segment.

Question 16

Your program will work as long as it does not generate compiler errors.

Accepted Answer

A program may not work correctly even if it doesn't generate compiler errors, as it could still have logical errors or runtime errors.

Question 17

FileNotFoundException is related to the Exception class because FileNotFoundException is a subclass of the IOException class, which is a subclass of the Exception class.

Accepted Answer

FileNotFoundException is a subclass of IOException, which in turn is a subclass of Exception, making it related to the Exception class.

Question 18

Sydney accidentally entered .5 instead of 5 in a code asking that she input an integer. She did not get a compiler error, but the program did not run because it generated an exception, which terminated the program.

Accepted Answer

Sydney entered a floating-point number instead of an integer, which is not a compiler error but will cause an exception at runtime.

Question 19

When is it good practice to call the close method?

Accepted Answer

Closing a file is good practice in all these scenarios to free up system resources, prevent data corruption, and ensure data is properly saved.

Question 20

Professor Simmons had a text file of students in his first-year economics class last semester. This semester, he has all new students. What action should he take to create a useful file for this semester?

Accepted Answer

The answer of Professor Simmons had a text file of...

Quiz 11: Exceptions, and Input Output Operations