Question 1

When reading words with a Scanner object, a word is defined as ____.
A)any sequence of characters consisting of letters only.
B)any sequence of characters consisting of letters, numbers, and punctuation symbols only.
C)any sequence of characters consisting of letters and numbers only.
D)any sequence of characters that is not white space.

Accepted Answer

A word is defined as any sequence of characters that is not white space. This means that punctuation symbols, numbers, and letters can all be included in a word as long as there are no spaces in between the characters.

Question 2

Consider the following code snippet.
File hoursFile = new File("hoursWorked.txt");
Your program must read the contents of this file using a Scanner object.Which of the following is the correct syntax for doing this?
A)Scanner in = new Scanner("hoursWorked.txt");
B)Scanner in = new Scanner(hoursFile);
C)Scanner in = Scanner.open(hoursFile);
D)Scanner in = Scanner("hoursWorked.txt");

Accepted Answer

The correct syntax for creating a Scanner object to read the contents of a file is to pass in a File object as the parameter, as shown in choice B. Choice A creates a Scanner object that reads from a string rather than a file. Choice C is not a valid syntax for creating a Scanner object. Choice D is missing the "new" keyword for creating a new object.

Question 3

Which method of the JFileChooser object will return the file object that describes the file chosen by the user at runtime?
A)getSelectedFilePath()
B)getSelectedFile()
C)getFilePath()
D)getFile()

Accepted Answer

The getSelectedFile() method returns the file object that describes the file chosen by the user at runtime, so it is the best choice for this scenario. The other methods listed do not exist in the JFileChooser class and will produce errors if attempted to be used.

Question 4

Insert the missing code in the following code fragment.This fragment is intended to write an output file named dataOut.txt that resides in a folder named reports on the C: drive of a Windows system.  
A)new PrintWriter("c:\reports\dataOut.txt")
B)new PrintWriter("c:/reports/dataOut.txt")
C)new PrintWriter("c://reports//dataOut.txt")
D)new PrintWriter("c:eports\dataOut.txt")

Accepted Answer

The answer of Insert the missing code in the following...

Question 5

Which of the following statements about using a PrintWriter object is NOT true?
A)PrintWriter is an enhancement of the PrintStream class.
B)A program can write to a PrintWriter using println.
C)A PrintWriter will be automatically closed when the program exits.
D)Data loss may occur if a program fails to close a PrintWriter object before exiting.

Accepted Answer

A PrintWriter will not be automatically closed when the program exits. It is important to manually close the PrintWriter in order to prevent potential data loss.

Question 6

Insert the missing code in the following code fragment.This fragment is intended to read a web page.  
A)new Scanner(pageLocation.openStream())
B)new Scanner(new File(pageLocation))
C)new Scanner("http://horstmann.com/index.html")
D)new Scanner(pageLocation)

Accepted Answer

The answer of Insert the missing code in the following...

Question 7

Insert the missing code in the following code fragment.This fragment is intended to read an input file named hoursWorked.txt.You want the program to terminate if the file does not exist.  
A)throws FileMissingException
B)catch FileNotFoundException
C)catch FileMissingException
D)throws FileNotFoundException

Accepted Answer

The answer of Insert the missing code in the following...

Question 8

Insert the missing code in the following code fragment.This fragment is intended to read an input file named dataIn.txt that resides in a folder named payroll on the C: drive of a Windows system.  
A)new File(c://payroll//"dataIn.txt")
B)new File("c:\payroll\dataIn.txt")
C)new File("c:\payroll\dataIn.txt")
D)new File(c:/payroll/"dataIn.txt")

Accepted Answer

The correct format for specifying a file path on a Windows system is to use double backslashes to separate the directory names. Therefore, option C is the correct choice, which specifies the correct file path of "c:\payroll\dataIn.txt". Option A is incorrect because it uses forward slashes instead of backslashes. Option B is incorrect because it only uses one backslash to separate directory names. Option D is incorrect because it uses a mixture of forward slashes and quotes, which is not a valid file path format.

Question 9

Consider the following code snippet.
Scanner inputFile = new Scanner("hoursWorked.txt");
Which of the following statements is correct?
A)This code will open an existing file named "hoursWorked.txt" for reading.
B)This code will create a new file named "hoursWorked.txt".
C)This code will treat the string "hoursWorked.txt" as an input value.
D)This code will open a file named "hoursWorked.txt" for writing.

Accepted Answer

The code snippet incorrectly uses the Scanner constructor with a string literal, which means it will treat "hoursWorked.txt" as the actual data to scan, not as a filename to open.

Question 10

Insert the missing code in the following code fragment.This fragment is intended to allow the user to select a file to be opened.  
A)chooser.getFileName()
B)chooser.getSelectedFileName()
C)chooser.getSelectedFile()
D)chooser.getFilePath()

Accepted Answer

The method getSelectedFile() returns the selected file as a File object, which can then be used to read the contents of the file.

Question 11

Assuming that inputFile is a Scanner object used to read words from a text file, select an expression to complete the following code segment, which counts the number of words in the input file.  
A)inputFile.nextString()
B)inputFile.nextDouble()
C)inputFile.next()
D)inputFile.nextInt()

Accepted Answer

The method .next() of the Scanner class reads the next complete token from the input file, which by default is any sequence of characters separated by whitespace (spaces, newlines, tabs, etc.). Therefore, using .next() will correctly count the number of words in the input file. None of the other choices would work in this case, as they would either skip over some of the words or throw an exception if the input file contains non-numeric characters.

Question 12

Which of the following statements about character encodings is NOT true?
A)It is recommended to specify the UTF-8 encoding when processing files with special symbols or characters in multiple languages.
B)Java assumes the UTF-8 encoding.
C)A character is encoded as a sequence of bytes, each having a value between 0 and 255.
D)Java supports the reading and writing of files in the UTF-8 encoding.

Accepted Answer

Java does not assume UTF-8 encoding by default; it uses the platform's default character encoding if not specified otherwise. UTF-8 must be explicitly specified when needed.

Question 13

Your program wishes to open a file named C:\java\myProg\input.txt on a Windows system.Which of the following is the correct code to do this?
A)inputFile = new File("c:\java\myProg\input.txt");
B)inputFile = new File.open("c:\java\myProg\input.txt");
C)inputFile = new File("c:\java\myProg\input.txt");
D)inputFile = new File.open("c:\java\myProg\input.txt");

Accepted Answer

Option C is the correct code to open a file named input.txt located in the directory C:\java\myProg\ on a Windows system. In Java, to represent a backslash character in a path, we need to use two backslashes (\) instead of a single one (\). Hence, option C uses the correct syntax to represent the path C:\java\myProg\input.txt. Option A is incorrect because it uses a single backslash instead of two backslashes to represent the path. Option B is incorrect because there is no method called "open()" in the File class. Option D is incorrect because it uses a single backslash instead of two backslashes and it also uses the non-existent "open()" method.

Question 14

Which return value of the JFileChooser object's showOpenDialog method indicates that a file was chosen by the user at run time?
A)OK_OPTION
B)SELECTED_OPTION
C)CANCEL_OPTION
D)APPROVE_OPTION

Accepted Answer

The JFileChooser object's showOpenDialog method returns APPROVE_OPTION when the user selects a file and clicks on the "Open" button. This is the option that indicates that a file was chosen by the user at run time. The other options are CANCEL_OPTION, which indicates that the user clicked on the "Cancel" button, and OK_OPTION and SELECTED_OPTION, which are not valid return values for the showOpenDialog method.

Question 15

Consider the following code snippet.
PrintWriter outputFile = new PrintWriter("payrollReport.txt");
Which of the following statements about the PrintWriter object is correct?
A)If a file named "payrollReport.txt" already exists, a new file named "payrollReport_1.txt" will be created and used.
B)If a file named "payrollReport.txt" already exists, an exception will occur.
C)If a file named "payrollReport.txt" already exists, existing data will be deleted before new data are added to the file.
D)If a file named "payrollReport.txt" already exists, new data will be added to the end of the file.

Accepted Answer

When a PrintWriter object is created with the name of a file, if the file already exists, its existing data will be deleted, and the file will be used as if it were a new file. This means any existing content in "payrollReport.txt" will be erased before new data is written to it.

Question 16

Consider the following code snippet.
Scanner inputFile = new Scanner("dataIn.txt");
Which of the following statements is correct?
A)This code will not open a file named "dataIn.txt", but will treat the string "dataIn.txt" as an input value.
B)This code will open a file named "dataIn.txt" for writing.
C)This code will create a new file named "dataIn.txt".
D)This code will open an existing file named "dataIn.txt" for reading.

Accepted Answer

The provided code snippet initializes a Scanner object with a string literal, which means the Scanner will treat the string "dataIn.txt" as the actual data to be scanned, not as a file path. To open a file, a File object or similar would need to be passed to the Scanner.

Question 17

Your program must read in an existing text file.You want the program to terminate if any exception related to the file occurs.Which of the following indicates the correct code for the header of the main method?
A)public static void main(String[] args) throws FileNotFoundException
B)public static void main(String[] args)
C)public static void main(String[] args) throws IOException
D)public static void main(String[] args) throws UnknownFileException

Accepted Answer

Option C is correct because IOException is a broader exception that encompasses FileNotFoundException and other types of I/O related exceptions, making it suitable for a program that wants to terminate upon encountering any file-related issues.

Question 18

Which of the following statements about reading web pages is true?
A)A Scanner object cannot be used to read a web page.
B)You must create a URL object to use with a Scanner object to read a web page.
C)You must use the openStream() method of a Scanner object to read a web page.
D)You must create a File object to use with a Scanner object to read a web page.

Accepted Answer

To read a web page using a Scanner object, you need to create a URL object and pass it as a parameter to the Scanner constructor. The Scanner object will then use this URL object to read the web page.

Question 19

Which Java class implements a file dialog box for selecting a file by a program with a graphical user interface?
A)JOptionPane
B)JFileChooser
C)JFilePane
D)JFileOption

Accepted Answer

JFileChooser is the Java class that implements a file dialog box for selecting a file by a program with a graphical user interface. This class provides a customizable file selection dialog as a modal dialog or as an internal panel within a parent component.

Question 20

Consider the following code snippet.  Which of the following statements about this code is correct? 
A)This code will read in a word at a time from the input file.
B)This code will read in a line at a time from the input file.
C)This code will read in the entire input file in one operation.
D)This code will read in a character at a time from the input file.

Accepted Answer

The answer of Consider the following code snippet.  Which...

Quiz 11: Input/Output and Exception Handling

When reading words with a Scanner object, a word is defined as ____.

Consider the following code snippet. File hoursFile = new File("hoursWorked.txt") ; Your program must read the contents of this file using a Scanner object.Which of the following is the correct syntax for doing this?

Which method of the JFileChooser object will return the file object that describes the file chosen by the user at runtime?

Which of the following statements about using a PrintWriter object is NOT true?

Insert the missing code in the following code fragment.This fragment is intended to read a web page.

Insert the missing code in the following code fragment.This fragment is intended to read an input file named hoursWorked.txt.You want the program to terminate if the file does not exist.

Consider the following code snippet. Scanner inputFile = new Scanner("hoursWorked.txt") ; Which of the following statements is correct?

Insert the missing code in the following code fragment.This fragment is intended to allow the user to select a file to be opened.

Assuming that inputFile is a Scanner object used to read words from a text file, select an expression to complete the following code segment, which counts the number of words in the input file.

Which of the following statements about character encodings is NOT true?

Your program wishes to open a file named C:\java\myProg\input.txt on a Windows system.Which of the following is the correct code to do this?

Which return value of the JFileChooser object's showOpenDialog method indicates that a file was chosen by the user at run time?

Consider the following code snippet. PrintWriter outputFile = new PrintWriter("payrollReport.txt") ; Which of the following statements about the PrintWriter object is correct?

Consider the following code snippet. Scanner inputFile = new Scanner("dataIn.txt") ; Which of the following statements is correct?

Your program must read in an existing text file.You want the program to terminate if any exception related to the file occurs.Which of the following indicates the correct code for the header of the main method?

Which of the following statements about reading web pages is true?

Which Java class implements a file dialog box for selecting a file by a program with a graphical user interface?

Consider the following code snippet. Which of the following statements about this code is correct?