Deck 11: Inputoutput and Exception Handling

Question 1

Under which condition will the PrintWriter constructor generate a FileNotFoundException?
A.If the output file does not exist.
B.If the output file cannot be opened or created due to a security error.
C.If the output file already exists, but is empty.
D.If the output file already exists, but has data in it.

Answer 1

If the output file cannot be opened or created due to a security error.

Question 2

Which of the following objects should be used for reading from a text file?
A.Scanner
B.PrintStream
C.ReadStream
D.ReadFile

Answer 2

Scanner

Question 3

Your program will read in an existing text file.You want the program to terminate if the file does not exist.Which of the following indicates the correct code for the main method header?
A.public static void main(String[] args) throws FileNotFoundException
B.public static void main(String[] args) throws UnknownFileException
C.public static void main(String[] args)
D.public static void main(String[] args) throws FileMissingException

Answer 3

public static void main(String[] args) throws FileNotFoundException

Question 4

Consider the following code snippet: Which of the following statements about this code is correct?
A.The main method is designed to catch and handle all types of exceptions.
B.The main method will not terminate if any exception occurs.
C.The main method is designed to catch and handle the FileNotFoundException.
D.The main method terminates if the FileNotFoundException occurs.

Question 5

Insert the missing code in the following code fragment.This fragment is intended to read an input file named dataIn.txt.
A.finally FileNotFoundException
B.throws FileNotFoundException
C.extends FileNotFoundException
D.catches FileNotFoundException

Question 6

Insert the missing code in the following code fragment.This fragment is intended to read an input file named dataIn.txt.
A.new Scanner(inputFile)
B.new Scanner(inputFileName)
C.new Scanner(outputFileName)
D.new Scanner(System.in)

Question 7

Under which condition will the Scanner constructor generate a FileNotFoundException?
A.If the input file already exists, but is empty.
B.If the input file does not exist.
C.If any I/O error occurs while opening the file.
D.If the input file already exists, but has data in it.

Question 8

The PrintWriter class is an enhancement of the ____ class.
A.File
B.ReadStream
C.Scanner
D.PrintStream

Question 9

Insert the missing code in the following code fragment.This fragment is intended to read an input file named dataIn.txt and write to an output file named dataOut.txt.
A.new File("dataIn.txt")
B.new Scanner(inputFile)
C.new Scanner("dataIn.txt")
D.new File(inputFileName)

Question 10

Which of the following statements reflects the recommendations about closing files?
A.Only the output file must be explicitly closed in the program.
B.Both the input and the output file should be explicitly closed in the program.
C.Only the input file must be explicitly closed in the program.
D.Both the input and the output file should not be explicitly closed in the program.

Question 11

Consider the following code snippet:
public static void main(String[] args) throws IOException
Which of the following statements about this code is correct?
A.The main method will not terminate if any exception occurs.
B.The main method is designed to catch and handle all types of exceptions.
C.The main method is designed to catch and handle the IOException.
D.The main method terminates if the IOException occurs.

Question 12

Select an expression to complete the following statement, which is designed to construct a PrintWriter object to write the program output to a file named dataout.txt.
PrintWriter theFile = _______________________;
A.new Scanner("dataout.txt")
B.new File("dataout.txt")
C.new PrintWriter("dataout.txt")
D.new PrintStream("dataout.txt")

Question 13

Which of the following statements about reading and writing text files is correct?
A.You use the Scanner class to read text files and the PrintWriter class to write text files.
B.You use the Scanner class to write text files and the PrintWriter class to read text files.
C.You use the Scanner class to read and write text files.
D.You use the PrintWriter class to read and write text files.

Question 14

Which of the following statements about a PrintWriter object is true?
A.A PrintWriter will be automatically closed when the program exits.
B.No data loss will occur if the program fails to close a PrintWriter before exiting.
C.An exception will occur if the program fails to close a PrintWriter before exiting.
D.Data loss may occur if a program fails to close a PrintWriter object before exiting.

Question 15

Which of the following statements about using the PrintWriter object is correct?
A.If the output file does not exist, a FileNotFoundException will occur.
B.If the output file already exists, the new data will be appended to the end of the file.
C.If the output file does not exist, an IllegalArgumentException will occur.
D.If the output file already exists, the existing data will be discarded before new data are written into the file.

Question 16

Consider the following code snippet:
File inputFile = new File("input.txt");
You wish to 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("input.txt");
B.Scanner in = new Scanner(inputFile);
C.Scanner in = Scanner.open(inputFile);
D.Scanner in = Scanner("input.txt");

Question 17

Insert the missing code in the following code fragment.This fragment is intended to read an input file named dataIn.txt and write to an output file named dataOut.txt.
A.new File(inputFile)
B.new File(System.in)
C.new File(outputFileName)
D.new File(inputFileName)

Question 18

Which of the following is the correct syntax for creating a File object?
A.File inFile = new File("input.txt");
B.File inFile = File.open("input.txt");
C.File inFile = File("input.txt");
D.File inFile = new File.open("input.txt");

Question 19

Insert the missing code in the following code fragment.This fragment is intended to read a file named dataIn.txt and write to a file named dataOut.txt.
A.new PrintWriter(outputFile)
B.new PrintWriter(outputFileName)
C.new Scanner(outputFile)
D.new Scanner(outputFileName)

Question 20

Consider the following code snippet:
PrintWriter out = new PrintWriter("output.txt");
If a file named "output.txt" already exists, which of the following statements about the PrintWriter object is correct?
A.An exception will occur.
B.Existing data will be deleted before data are added to the file.
C.A new file named "output_1.txt" will be created and used.
D.Data will be added at the end of the file.

Question 21

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.

Question 22

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");

Question 23

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()

Question 24

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:\reports\dataOut.txt")

Question 25

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.

Question 26

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)

Question 27

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

Question 28

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")

Question 29

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.

Question 30

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()

Question 31

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()

Question 32

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.

Question 33

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");

Question 34

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

Question 35

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.

Question 36

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.

Question 37

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

Question 38

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.

Question 39

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

Question 40

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.

Question 41

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

Question 42

Insert the missing code in the following code fragment.This fragment is intended to read floating-point numbers from a text file.
A.in.getNextDouble()
B.in.hasNextDouble()
C.in.hasNextInt()
D.in.peek()

Question 43

Consider the following code snippet: If there is no integer number appearing next in the input, what will occur?
A.ageValue will contain a null value.
B.ageValue will contain a zero.
C.An exception will occur.
D.ageValue will contain whatever characters are encountered.

Question 44

Assume inputFile is a Scanner object used to read data from a text file that contains a number of lines.Some lines contain an alphabetic string, while others contain a single integer value.Select an expression to complete the following code segment, which counts the number of integer values in the input file.
A.inputFile.hasNext()
B.inputFile.hasNextInt()
C.Character.isDigit(inputFile.next())
D.inputFile.nextInt()

Question 45

Assume inputFile is a Scanner object used to read data from a text file that contains a number of lines.Each line contains an arbitrary number of words, with at least one word per line.Select an expression to complete the following code segment, which prints the last word in each line.
A.words.hasNext()
B.line.hasNext()
C.words.hasNextInt()
D.inputFile.hasNext()

Question 46

Which of the following statements about white space in Java is correct?
A.In Java, white space includes spaces, tab characters, newline characters, and punctuation.
B.In Java, white space includes spaces and tab characters only.
C.In Java, white space includes spaces, tab characters, and newline characters.
D.In Java, white space includes spaces only.

Question 47

Consider the following code snippet: If the input file begins with the characters 626.14 average, what values will number and result have after this code is executed?
A.number will contain the value 0 and result will contain the value average.
B.number will contain the value 626.14 and result will contain the value average.
C.number will contain the value 626 and result will contain the value 14.
D.number will contain the value 0 and result will contain the value 626.14.

Question 48

You wish to use the Scanner class's nextInt() method to read in whole numbers.To avoid exceptions that would occur if the input is not a whole number, you should use the ____ method before calling nextInt().
A.hasNextInteger()
B.hasNext()
C.hasNextInt()
D.hasIntegerValue()

Question 49

Consider the following code snippet: If the input file contains the characters 626.14 average, what values will number and result have after this code is executed?
A.number will contain the value 0 and result will contain the value 626.14.
B.number will contain the value 626.14 and result will contain the value average.
C.number will contain the value 626 and result will contain the value 14.
D.number will contain the value 0 and result will contain the value average.

Question 50

Consider the following code snippet. Which of the following statements about this code is correct?
A.The methods of the Scanner class can be used on line to scan the string.
B.The methods of the Scanner class can be used on lineScanner to scan the string.
C.This code will not compile because a Scanner cannot be constructed on a String.
D.This code compiles but generates a run-time exception.

Question 51

Insert the missing code in the following code fragment.This fragment is intended to read characters from a text file.
A.in.getNext()
B.in.next().charAt(0)
C.in.next()
D.in.nextChar()

Question 52

The ____ method of the Character class will indicate if a character contains white space.
A.isValid()
B.getChar()
C.hasNext()
D.isWhiteSpace()

Question 53

The ______ method of the Scanner class specifies a pattern for word boundaries when reading text.
A.setDelimiter()
B.usePattern()
C.useDelimiter()
D.setPattern()

Question 54

Which String class method will remove spaces from the beginning and the end of a string?
A.clean()
B.strip()
C.truncate()
D.trim()

Question 55

Which expression converts the string input containing floating-point digits to its floating-point value?
A.input.parseFloat()
B.input.parseDouble()
C.Double.parseDouble(input)
D.Float.parseFloat(input)

Question 56

Consider the following code snippet: Which of the following statements about this code is correct?
A.This code will read in a single character from the file in each iteration of the loop.
B.This code will read in the entire contents of the file in a single iteration of the loop.
C.This code will read in a single word from the file in each iteration of the loop.
D.This code will read in an entire line from the file in each iteration of the loop.

Question 57

Insert the missing code in the following code fragment.This fragment is intended to read all words from a text file named dataIn.txt.
A.in.getNext()
B.in.nextWord()
C.in.hasNext()
D.in.peek()

Question 58

Which of the following patterns should be used for the delimiter to read one character at a time using a Scanner object's next method?

Question 59

Assuming that the string input contains the digits of an integer, without any additional characters, which expression obtains the corresponding numeric value?
A.Integer.parseInteger(input)
B.Integer.parseInt(input)
C.Int.parseInt(input)
D.input.parseInt()

Question 60

When reading words using a Scanner object's next method, ____.
A.the program must discard white space characters at the beginning of the input before calling the next method
B.any characters that are considered to be white space within the word become part of the word
C.any characters at the beginning of the input that are considered to be white space are consumed and become part of the word being read
D.any characters at the beginning of the input that are considered to be white space are consumed and do not become part of the word being read

Question 61

Consider the following code snippet: What characters will be ignored and not read in when using this code?
A.Only numeric characters will be ignored.
B.Only non-alphabetic characters will be ignored.
C.Only alphabetic characters will be ignored.
D.Only non-numeric characters will be ignored.

Question 62

You have opened a command prompt window and you have entered the following:
java myProg Bob Smith
Which of the following statements is correct?
A.You have supplied two argument values, and these values can be accessed in the main method using the args parameter.
B.You have supplied one argument value, and this value can be accessed in the main method using the arg1 parameter.
C.You have supplied one argument value, and this value can be accessed in the main method using the args parameter.
D.You have supplied two argument values, and these values can be accessed in the main method using the arg1 and arg2 parameters.

Question 63

Consider the following code snippet, assuming that description is a String and totalPrice is a double:
System.out.printf("%-12s%8.2f",description,totalPrice);
Which of the following statements is correct?
A.This code will produce 2 columns, with the description field left justified and the totalPrice field left justified.
B.This code will produce 2 columns, with the description field right justified and the totalPrice field left justified.
C.This code will produce 2 columns, with the description field right justified and the totalPrice field right justified.
D.This code will produce 2 columns, with the description field left justified and the totalPrice field right justified.

Question 64

When you start a Java program from a command line and supply argument values, the values ____.
A.are stored as float values
B.are stored as int values
C.are stored as String values
D.are stored as the type of value indicated by the argument

Question 65

Consider the following code snippet: What characters will be ignored and not read in using this code?
A.Only numeric characters will be ignored.
B.Only non-alphabetic characters will be ignored.
C.Only alphabetic characters will be ignored.
D.Only non-numeric characters will be ignored.

Question 66

Which of the following statements about exception reporting is true?
A.Use the throw statement to report that an exception has occurred.
B.Use the reportError statement to report that an exception has occurred.
C.Use the reportException statement to report that an exception has occurred.
D.Use the throwException statement to report that an exception has occurred.

Question 67

Which of the following statements about exception handling is correct?
A.Statements that may cause an exception should be placed within a catch block.
B.Statements that may cause an exception should be placed within a try block.
C.The main method of a Java program will handle any error encountered in the program.
D.Statements that may cause an exception should be placed within a throws block.

Question 68

Consider the following code snippet:
throw IllegalArgumentException("This operation is not allowed!");
Which of the following statements about this code is correct?
A.This code constructs an object of type IllegalArgumentException and throws the object.
B.This code throws an existing IllegalArgumentException object.
C.This code constructs an object of type IllegalArgumentException and reserves it for future use.
D.This code will not compile.

Question 69

Select an expression to complete the program segment below, which displays an error message and terminates normally if the String variable accountNumber does not contain an integer value.
A.NumberFormatException exception
B.InputMismatchException exception
C.ArithmeticException exception
D.IOException exception

Question 70

Consider the following code snippet: What characters will be read in using this code?
A.Only alphabetic characters will be read in.
B.Only numeric characters will be read in.
C.Only non-numeric characters will be read in.
D.Only non-alphabetic characters will be read in.

Question 71

Consider the following code snippet: What characters will be ignored and not read in using this code?
A.Both alphabetic and numeric characters will be ignored.
B.Only numeric characters will be ignored.
C.Characters that are neither alphabetic nor numeric will be ignored.
D.Only alphabetic characters will be ignored.

Question 72

Assume inputFile is a Scanner object used to read data from a text file that contains a series of double values.Select an expression to complete the following code segment, which reads the values and prints them in standard output, one per line, in a field 15 characters wide, with two digits after the decimal point.
A.System.out.printf("%15f",value);
B.System.out.printf("%.2f",value);
C.System.out.printf("%15.2f\n",value);
D.System.out.printf("%15.2f",value);

Question 73

Complete the code fragment below, which is designed to throw an exception if String variable accountNumber has more than seven characters.
A.throws new IllegalArgumentException("Account number exceeds maximum length");
B.throw new IllegalArgumentException("Account number exceeds maximum length");
C.throws IllegalArgumentException("Account number exceeds maximum length");
D.throw IllegalArgumentException("Account number exceeds maximum length");

Question 74

Select an expression to complete the program segment below, which is designed to read data from a file whose name is specified as the first command line argument.If no command line arguments are given, the program reads data from the default.txt file.
A.args > 0
B.args[0] != null
C.args.length >= 0
D.args.length > 0

Question 75

Consider the following code snippet:
throw new IllegalArgumentException("This operation is not allowed!");
Which of the following statements about this code is correct?
A.This code throws an existing IllegalArgumentException object.
B.This code will not compile.
C.This code constructs an object of type IllegalArgumentException and throws the object.
D.This code constructs an object of type IllegalArgumentException and reserves it for future use.

Question 76

Which statement about handling exceptions is true?
A.If an exception has no handler, the program will be terminated.
B.If an exception has no handler, the error will be ignored.
C.Statements to handle exceptions should be placed inside a try clause.
D.Statements that may cause exceptions should be placed inside a catch clause.

Question 77

What is the purpose of the throw statement?
A.It is used to pass control to an error handler when an error situation is detected.
B.It is used to discard erroneous input.
C.It is used to detect an error situation.
D.It is used to pass arguments to another method.

Question 78

Which of the following statements about command line arguments is correct?
A.You must declare additional parameters in the main method to receive command line argument values.
B.You cannot pass arguments to a program when starting the program from a command line prompt.
C.Command line arguments can be read using the main method's args parameter.
D.Command line arguments must be read with a Scanner object.

Question 79

In the hierarchy of Exception classes, the NumberFormatException class is a subclass of the ____ class.
A.ClassCastException
B.IllegalStateException
C.IllegalArgumentException
D.ArithmeticException

Question 80

Which of the following is the correct syntax for starting a Java program named myProg from a command line if the program requires two arguments named arg1 and arg2 to be supplied?
A.java myProg(arg1, arg2)
B.java myProg "arg1" "arg2"
C.java myProg arg1 arg2
D.java myProg arg1, arg2