Question 1

Which of the following statements is false?

Accepted Answer

A) A LineNumberReader is a buffered character stream that tracks the number of lines read. 
B) Classes FileReader and FileWriter perform character-based file I/O. 
C) Class PipedReader and class PipedWriter implement piped-character streams for transferring data between threads. 
D) Class StringReader and StringWriter read characters from and write characters to Streams,respectively. 
A) A LineNumberReader is a buffered character stream that tracks the number of lines read. 
B) Classes FileReader and FileWriter perform character-based file I/O. 
C) Class PipedReader and class PipedWriter implement piped-character streams for transferring data between threads. 
D) Class StringReader and StringWriter read characters from and write characters to Streams,respectively. D

Question 2

Which of the following statements is false?

Accepted Answer

A) Path method isAbsolute returns a boolean indicating whether a Path represents an absolute path to a file or directory. 
B) Files static method getLastModifiedTime receives a Path and returns a FileTime (package java.nio.file.attribute)indicating when the file was last modified. 
C) Files static method size receives a Path and returns a long representing the number of bytes in the file or directory.For directories,the value returned is platform specific. 
D) All of the above are true. 
A) Path method isAbsolute returns a boolean indicating whether a Path represents an absolute path to a file or directory. 
B) Files static method getLastModifiedTime receives a Path and returns a FileTime (package java.nio.file.attribute)indicating when the file was last modified. 
C) Files static method size receives a Path and returns a long representing the number of bytes in the file or directory.For directories,the value returned is platform specific. 
D) All of the above are true. D

Question 3

Which of the following statements is true?

Accepted Answer

A) Class Scanner provides the ability to reposition to the beginning of a file with method seek. 
B) Class Scanner provides the ability to reposition to the beginning of a file with method reposition. 
C) Class Scanner does not provide the ability to reposition to the beginning of the file. 
D) If it is necessary to read a sequential file again,the program can simply keep reading-when the end of the file is reached,the Scanner is automatically set to point back to the beginning of the file. 
A) Class Scanner provides the ability to reposition to the beginning of a file with method seek. 
B) Class Scanner provides the ability to reposition to the beginning of a file with method reposition. 
C) Class Scanner does not provide the ability to reposition to the beginning of the file. 
D) If it is necessary to read a sequential file again,the program can simply keep reading-when the end of the file is reached,the Scanner is automatically set to point back to the beginning of the file. C

Question 4

A serialized object is ________.

Accepted Answer

A) an object represented as a sequence of bytes used to store the object's data in a file 
B) an object in memory that has been recreated from data in a file 
C) a standard output stream object used to convert objects in code to data in a file 
D) None of the above. 
A) an object represented as a sequence of bytes used to store the object's data in a file 
B) an object in memory that has been recreated from data in a file 
C) a standard output stream object used to convert objects in code to data in a file 
D) None of the above.

Question 5

How do methods setIn,setOut and setErr affect the standard input,output and error streams?

Accepted Answer

A) They output data to the standard input,output and error streams. 
B) They provide the only way to access the standard input,output and error streams. 
C) They redirect the standard input,output and error streams. 
D) They empty the standard input,output and error streams. 
A) They output data to the standard input,output and error streams. 
B) They provide the only way to access the standard input,output and error streams. 
C) They redirect the standard input,output and error streams. 
D) They empty the standard input,output and error streams.

Question 6

Class ________ provides static methods for common file and directory manipulations,including methods for copying files;creating and deleting files and directories;getting information about files and directories;reading the contents of files;getting objects that allow you to manipulate the contents of files and directories;and more.

Accepted Answer

A) File 
B) FileAndDirectory 
C) Files 
D) FilesAndDirectories 
A) File 
B) FileAndDirectory 
C) Files 
D) FilesAndDirectories

Question 7

Which of the following classes is not used for file input?

Accepted Answer

A) FileInputStream 
B) FileReader 
C) ObjectInputStream 
D) Formatter 
A) FileInputStream 
B) FileReader 
C) ObjectInputStream 
D) Formatter

Question 8

Instance variables that are not to be output with a Serializable object are declared using which keyword?

Accepted Answer

A) private 
B) ignoreme 
C) transient 
D) persistent 
A) private 
B) ignoreme 
C) transient 
D) persistent

Question 9

Which JFileChooser method returns the file the user selected?

Accepted Answer

A) getSelectedFile. 
B) getFile. 
C) getOpenDialog. 
D) showOpenDialog. 
A) getSelectedFile. 
B) getFile. 
C) getOpenDialog. 
D) showOpenDialog.

Question 10

Which statement regarding Java files is false?

Accepted Answer

A) Java imposes no structure on a file. 
B) Notions like "record" do not exist in Java files. 
C) The programmer must structure files to meet the requirements of applications. 
D) Records in a Java sequential file are stored in order by record key. 
A) Java imposes no structure on a file. 
B) Notions like "record" do not exist in Java files. 
C) The programmer must structure files to meet the requirements of applications. 
D) Records in a Java sequential file are stored in order by record key.

Question 11

When using an ObjectInputStream to read data from a file,what happens when an end-of-file marker is reached?

Accepted Answer

A) Nothing occurs. 
B) An end-of-file character is read by the program. 
C) Method readObject returns the value 0. 
D) An EOFException is thrown. 
A) Nothing occurs. 
B) An end-of-file character is read by the program. 
C) Method readObject returns the value 0. 
D) An EOFException is thrown.

Question 12

What interface must a class implement to indicate that objects of the class can be output and input as a stream of bytes?

Accepted Answer

A) Synchronize 
B) Deserializable 
C) Serializable 
D) ObjectOutput 
A) Synchronize 
B) Deserializable 
C) Serializable 
D) ObjectOutput

Question 13

Which of the following classes enable input and output of entire objects to or from a file?
a)SerializedInputStream
b)SerializedOutputStream
c)ObjectInputStream
d)ObjectOutputStream
e)Scanner
f)Formatter

Accepted Answer

A) A and B. 
B) C and D. 
C) C,D,E,F. 
D) E and F. 
A) A and B. 
B) C and D. 
C) C,D,E,F. 
D) E and F.

Question 14

Streams that input bytes from and output bytes to files are known as ________.

Accepted Answer

A) bit-based streams 
B) byte-based streams 
C) character-based streams 
D) Unicode-based streams 
A) bit-based streams 
B) byte-based streams 
C) character-based streams 
D) Unicode-based streams

Question 15

When all the contents of a file are truncated,this means that ________.

Accepted Answer

A) the data in the file is saved to a backup file 
B) the file is deleted 
C) a FileNotFoundException occurs 
D) all the data in the file is discarded 
A) the data in the file is saved to a backup file 
B) the file is deleted 
C) a FileNotFoundException occurs 
D) all the data in the file is discarded

Question 16

Adding the services of one stream to another is known as ________.

Accepted Answer

A) chaining 
B) wrapping 
C) adding 
D) sequencing 
A) chaining 
B) wrapping 
C) adding 
D) sequencing

Question 17

Which JFileChooser method specifies what users can select in the dialog?

Accepted Answer

A) setFileSelectionMode 
B) setSelectionMode 
C) showOpenDialog 
D) None of the above. 
A) setFileSelectionMode 
B) setSelectionMode 
C) showOpenDialog 
D) None of the above.

Question 18

Files static method ________ receives a Path and returns a boolean indicating whether that Path represents a directory on disk.

Accepted Answer

A) isDiskDirectory 
B) isDirectory 
C) isFileDirectory 
D) isPath 
A) isDiskDirectory 
B) isDirectory 
C) isFileDirectory 
D) isPath

Question 19

Which of the following statements is false?

Accepted Answer

A) InputStream and OutputStream are abstract classes for performing byte-based I/O. 
B) Tubes are synchronized communication channels between threads. 
C) A filter stream provides additional functionality,such as aggregating data bytes into meaningful primitive-type units.FilterInputStream and FilterOutputStream are typically extended,so some of their filtering capabilities are provided by their concrete subclasses. 
D) A PrintStream performs text output.System.out and System.err are PrintStreams. 
A) InputStream and OutputStream are abstract classes for performing byte-based I/O. 
B) Tubes are synchronized communication channels between threads. 
C) A filter stream provides additional functionality,such as aggregating data bytes into meaningful primitive-type units.FilterInputStream and FilterOutputStream are typically extended,so some of their filtering capabilities are provided by their concrete subclasses. 
D) A PrintStream performs text output.System.out and System.err are PrintStreams.

Question 20

The ________ abstract classes are Unicode character-based streams.

Accepted Answer

A) Reader and Writer 
B) BufferedReader and BufferedWriter 
C) CharArrayReader and CharArrayWriter 
D) UnicodeReader and UnicodeWriter 
A) Reader and Writer 
B) BufferedReader and BufferedWriter 
C) CharArrayReader and CharArrayWriter 
D) UnicodeReader and UnicodeWriter

Exam 15: Files,streams and Object Serialization

Which of the following statements is false?

Which of the following statements is false?

Which of the following statements is true?

A serialized object is ________.

How do methods setIn,setOut and setErr affect the standard input,output and error streams?

Which of the following classes is not used for file input?

Instance variables that are not to be output with a Serializable object are declared using which keyword?

Which JFileChooser method returns the file the user selected?

Which statement regarding Java files is false?

When using an ObjectInputStream to read data from a file,what happens when an end-of-file marker is reached?

What interface must a class implement to indicate that objects of the class can be output and input as a stream of bytes?

Which of the following classes enable input and output of entire objects to or from a file? a)SerializedInputStream b)SerializedOutputStream c)ObjectInputStream d)ObjectOutputStream e)Scanner f)Formatter

Streams that input bytes from and output bytes to files are known as ________.

When all the contents of a file are truncated,this means that ________.

Adding the services of one stream to another is known as ________.

Which JFileChooser method specifies what users can select in the dialog?

Files static method ________ receives a Path and returns a boolean indicating whether that Path represents a directory on disk.

Which of the following statements is false?

The ________ abstract classes are Unicode character-based streams.

Introduction to Computers and Java

Introduction to Java Applications

Introduction to Classes and Objects

Control Statements: Part 1

Control Statements: Part 2

Methods: a Deeper Look

Arrays and Arraylists

Classes and Objects: a Deeper Look

Object Oriented Programming: Inheritance

Object-Oriented Programming: Polymorphism

Exception Handling

Gui Components: Part 1

Graphics and Java 2D

Strings

Generic Collections

Lambdas

Recursion

Searching, Sorting and Big O

Generic Classes and Methods

Custom Generic Data Structures

Concurrency

Accessing Databases With Jdbc

JavaFX

Filters