Java ch 15 Exercises

True

'Files static' method 'exists' receives a Path and determines whether it exists (either as a file or as a directory) on a disk. True False

opens

A Java program _____________ a file by creating an object and associating a stream of bytes or characters with it.

True

A Java program simply receives an indication from the operating system when it reaches the end of the stream

LineNumberReader

A ______________ (a subclass of Buffered-Reader) is a buffered character stream that keeps track of the number of lines read.

FilterInputStream, FilterOutputStream

A ______________ filters an InputStream, and a _______________ filters an OutputStream.

relative path

A _______________ is "relative" to another directory—for example, a path relative to the directory in which the application began executing.

serialized object

A ________________ is represented by XML that includes the object's data

separator character

A __________________ is used to separate directories and files in a path.

SecurityException

A ____________________ occurs if the user does not have permission to write data to the file.

PrintStream

A _____________________ (a subclass of FilterOutputStream) performs text output to the specified stream.

NoSuchElementException

A __________________________ occurs if the data being read by a Scanner method is in the wrong format or if there is no more data to input.

FileNotFoundException

A __________________________ occurs if the file does not exist and a new file cannot be created.

Uniform Resource Identifier (URI), Uniform Resource Locators (URLs)

A ______________________________ is a more general form of the ________________________________ that are used to locate websites.

flush

A partially filled buffer can be forced out to the device at any time by invoking the stream object's ___________ method.

deserialized

After a serialized object has been written into a file, it can be read from the file and _________________—that is, the XML that represents the object and its data can be used to recreate the object in memory\

InputStreamReader.

An InputStream can be converted to a Reader via class ______________

OutputStreamWriter.

An OuputStream can be converted to a Writer via class ___________________

absolute path, root directory

An ___________ contains all directories, starting with the ______________, that lead to a specific file or directory.

True

An absolute path contains all the directories, starting with the root directory, that lead to a specific file or directory. True False

@XMLElement, javax.xml.bind.annotation

Annotation______________ (line 9; package _______________________) indicates that the private instance variable should be serialized

Formatter

Character-based input and output can be performed with classes Scanner and ___________.

False Class Formatter contains method format, which enables formatted data to be output to the screen or to a file.

Class Formatter contains method printf, which enables formatted data to be output to the screen or to a file. True False

False. Class Scanner does not allow repositioning to the beginning of the file.

Class Scanner does allow repositioning to the beginning of the file.

setIn, setOut, setErr

Class System provides methods __________, ____________ and _____________ to redirect the standard input, output and error streams, respectively.

PipedReader, PipedWriter

Class _____________ and class ________________ implement piped-character streams for transfering data between threads.

Formatter

Class _____________ enables formatted data to be output to any text-based stream in a manner similar to method System.out.printf.

StringReader, StringWriter

Class _______________ and ___________ read characters from and write characters to Strings.

Scanner

Class _______________ is used extensively to input data from the keyboard. This class can also read data from a file.

java.io.PrintWriter

Class _________________ outputs data to a text file.

FileChooserTest

Class ___________________ launches the JavaFX application

FileChooserTestController

Class ______________________ responds to the Buttons' events

DataOutputStream

Classes ___________ (a subclass of FilterOutputStream) and RandomAccessFile each implement this interface to write primitive-type values as bytes.

CharArrayReader, CharArrayWriter

Classes ______________ and ____________________ read and write, respectively, a stream of characters to a char array.

BufferedReader, BufferedWriter

Classes ________________ (a subclass of abstract class Reader) and ________________ (a subclass of abstract class Writer) enable buffering for character-based streams.

DataInputStream

Classes ________________ and RandomAccessFile each implement this interface to read sets of bytes and process them as primitive-type values.

secondary storage devices

Computers store files on _______________ such as, hard disks, flash drives, DVDs and more.

persistent data

Data maintained in files is ____________ because it exists beyond the duration of program execution.

temporary

Data stored in variables and arrays is ____________. It's lost when a local variable goes out of scope or when the program terminates

redirected

Each stream can be _____________.

end-of-file marker

Every operating system provides a mechanism to determine the end of a file, such as an ____________________ or a count of the total bytes in the file that is recorded in a system-maintained administrative data structure.

False. File streams can be used to input and output data as bytes or characters.

File streams cannot be used to input and output data as bytes or characters.

text files

Files created using character-based streams are referred to as ___________. Text files can be read by text editors.

size

Files static method ___________ receives a Path and returns a long representing number of bytes in a file or directory.

newBufferedWriter, BufferedWriter

Files static method _____________, which receives a Path specifying the file to open for writing ("clients.xml") and—if the file exists—returns a __________________ that class JAXB will use to write text to the file

getLastModifiedTime

Files static method ______________ receives a Path and returns a FileTime indicating when the file was last modified.

isDirectory

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

files

For long-term retention of data, computers use ____________.

close

Formatter method ____________ closes the file.

format

Formatter method _______________ works like System.out.printf

IllegalStateException

If a Scanner is closed before data is input, an _______________________ occurs.

truncated.

If an existing file is opened, its contents are ______________.

new DirectoryStream

If the Path represents a directory use File static method _______________.

XML serialization, marshaling

JAXB enables you to perform _______________—which JAXB refers to as ________________.

unmarshal

JAXB static method ________________ reads the contents of clients.xml and convert the XML into an Accounts object

marshal

JAXB static method _________________ to serialize as XML the Accounts object containing the List<Account>

POJOs (plain old Java objects)

JAXB works with _______________________—no special superclasses or interfaces are required for XML-serialization support

java.io , java.nio.

Java programs perform file processing by using classes from package _____________ and the subpackages of _____________.

stream of bytes

Java views each file as a sequential ____________.

FileChooser, DirectoryChooser

JavaFX classes __________ and _____________________ (package javafx.stage) display dialogs that enable the user to select a file or directory, respectively

getFileName

Path method ________ returns the String name of a file or directory without any location information.

toAbsolutePath

Path method _____________ converts the Path on which it's called to an absolute path.

toString

Path method _____________ returns a String representing the Path.

isAbsolute

Path method ________________ returns a boolean indicating whether that Path represents an absolute path to a file or directory.

Reader, Writer

The _____________ and ______________ abstract classes are Unicode two-byte, character-based streams.

batch , shell script

The argument is useful if the program is executed from a __________ file on Windows or a _____________ on UNIX/Linux/Mac OS X.

logical output operations.

The output operations directed to the output buffer in memory are often called _______________________.

newBufferedReader, Buffered-Reader

The program opens the file for input by calling Files static method________________, which receives a Path specifying the file to open and, if the file exists and no exceptions occur, returns a _________________ for reading from the file.

physical output operation

Transfer to the output device is performed in one large ______________ each time the buffer fills.

True

When reading data from a file using class Scanner, if you wish to read data in the file multiple times, the file must be closed and reopened to read from the beginning of the file. True False

BufferedOutputStream, buffer

With a ________________, each output operation is directed to a ______________ larger enough to hold the data of many output operations

Scanner inTransaction = new Scanner(Paths.get("trans.txt"));

Write a statement tha opens files "trans.txt" for input-use Scanner variable inTransaction.

Formatter outNewMaster = new Formatter("newmast.txt");

Write a statement that opens file "newmast.txt" for output (and creation)-user formatter variable outNewMaster.

Scanner oldmastInput = new Scanner(Paths.get("oldmas.txt"));

Write a statement that opens file "oldmast.txt" for input-use Scanner variable inOldMaster

Accounts account = JAXB.unmarshal(reader, Accounts.class);

Write a statement that performs the following tasks: Input an XML serialized object into an Accounts object names accounts using a BufferedReader name reader

JAXB.marshal(accounts, writer);

Write a statement that performs the following tasks: Output an Accounts object names accounts using XML serialization and a BufferedWriter name writer

Account account = new Account(); account.setAccount(inOldMaster.next()); account.setFirstName(inOldMaster.next()); account.setLastName(inOldMaster.next()); account.setBalance(inOldMaster.nextDouble());

Write the statements needed to read a record form the file "oldmast.txt". Use the data to create an object of class Account-use Scanner variable inOldMaster. Assume that class Account is the same as the Account class in fig 15.9

TransactionRecord transaction = new Transactions(); transaction.setAccount(inTransaction.nextInt()); transaction.setAmount(inTransaction.nextDouble());

Write the statements needed to read a record fromt he file "trans.txt". Th record is an object of class TransactionRecord-use Scanner variable inTransaction. Assume tha class TransactionRecord contains method setAccount (which takes an int) to set the account number and method setAmount (which takes a double) to set the amount of the transaction.

False XML files are both computer and machine readable

XML files are not human readable in a text editor. True False

False These three streams are created for you when a Java application begins executing.

You must explicitly create the stream objects System.in, System.out and System.err. True False

Character-based streams

____________ output and input data as a sequence of characters in which every character is two bytes—the number of bytes for a given value depends on the number of characters in that value.

Pipes

______________ are synchronized communication channels between threads.

Binary files

_______________ are read by programs that understand the specific content of the file and the ordering of that content.

Byte-based streams

________________ output and input data in its binary format—a char is two bytes, an int is four bytes, a double is eight bytes, etc.

Filtering

_________________ means simply that the filter stream provides additional functionality, such as aggregating bytes into meaningful primitive-type units.

Sequential files

__________________ store records in order by the record-key field.

Buffering

____________________ is an I/O-performance-enhancement technique.

InputStream, OutputStream

______________________ and _____________ are abstract classes that declare methods for performing byte-based input and output, respectively.

PipedOutputStream (a subclass of OutputStream), PipedInputStream (a subclass of InputStream)

______________________________________ and ________________ establish pipes between two threads in a program.

FilterInputStream and FilterOutputStream

______________________________________________ are typically used as superclasses, so some of their filtering capabilities are provided by their subclasses.

DirectoryStream interface

_________________—Objects of classes that implement this interface enable a program to iterate through the contents of a directory.

Path interface

______________—Objects of classes that implement this interface represent the location of a file or directory. Path objects do not open files or provide any file-processing capabilities.

Paths class

_____________—Provides static methods used to get a Path object representing a file or directory location.

Files class

____________—Provides static methods for common file and directory manipulations, such as 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

get

class static method ____________ of class Paths to convert a String representing in a file's or directory's location into a Path object.

System.exit

static method ________________ terminates an application.

FormatterClosedException

that occurs if the Formatter object is closed when you attempt to use it.