Chapter 9: NIO 2

Question 1

can be used to get the operating system-dependent file separator from the JVM.

Answer 1

System.getProperty(“path.separator”)

Question 2

optional arguments in NIO.2,If provided, symbolic links when encountered will not be traversed. Useful for performing operations on symbolic links themselves rather than their target.

Answer 2

NOFOLLOW_LINKS

Question 3

optional arguments in NIO.2, If provided, symbolic links when encountered will be traversed.

Answer 3

FOLLOW_LINKS

Question 4

optional arguments in NIO.2, If provided, all metadata about a file will be copied with it.

Answer 4

COPY_ATTRIBUTES

Question 5

optional arguments in NIO.2, If provided and the target file exists, it will be replaced; otherwise, if it is not provided, an exception will be thrown if the file already exists.

Answer 5

REPLACE_EXISTING

Question 6

optional arguments in NIO.2, The operation is performed in an atomic manner within the file system, ensuring that any process using the file sees only a complete record. Method using it may throw an exception if the feature is unsupported by the file system.

Answer 6

ATOMIC_MOVE

Question 7

Path method, returns a String representation of the entire path.

Answer 7

Path.toString()

Question 8

Path method, retrieve the number of elements in the path

Answer 8

Path.getNameCount() int

Question 9

Path method, retrieve a reference to each element,

Answer 9

Path.getName(int i) - returns Path

Question 10

Path method, returns a Path instance representing the filename, which is the farthest element from the root

Answer 10

Path.getFileName - returns Path

Question 11

Path method, returns a Path instance representing the parent path or null if there is no such parent

Answer 11

Path.getParent() - returns Path

Question 12

Path method, returns the root element for the Path object or null if the Path object is relative.

Answer 12

Path.getRoot() - returns Path

Question 13

Path method, returns true if the path the object references is absolute and false if the path the object references is relative.

Answer 13

isAbsolute()

Question 14

Path method, converts a relative Path object to an absolute Path object by joining it to the current working directory

Answer 14

toAbsolutePath()

Question 15

Path method, returns a relative subpath of the Path object

Answer 15

Path.subpath(int, int) - returns Path,

Inclusive beginning index, exclusive end index

Question 16

Path method, for constructing the relative path from one Path object to another.

Answer 16

Path.relativize(path2) - result is path of path2 in relation to this path.

Question 17

Path method, for method for creating a new Path by joining an existing path to the current path.

Answer 17

Path.resolve(Path 2)

Question 18

Path method, method to eliminate the redundancies in the path.

Answer 18

Path.normalize()

Question 19

Path method, method takes a Path object that may or may not point to an existing file within the file system, and it returns a reference to a real path within the file system.

Answer 19

Path.toRealPath() - returns Path

Question 20

Path method, use the toRealPath() method to gain access to the current working directory

Answer 20

Paths.get(“.”).toRealPath()

Question 21

Files method, method takes a Path object and returns true if, and only if, it references a file that exists in the file system.

Answer 21

Files.exists(Path p)

Question 22

Files method, method is useful for determining if two Path objects relate to the same file within the file system

Answer 22

Files.isSameFile(Path p, Path p2)

returns true immediately when the two paths passes equals method.
throws IOException when the file does not exist.

Question 23

Files method, method to create a directory

Answer 23

Files.createDirectory - throws IOException when the parent directory does not exist or when the directory already exists or cannot be created.

Files.createDirectories()

Question 24

Files method, which copies a file or directory from one location to another.

Answer 24

Files.copy(Path p1, Path p2) - throws IOException when file does not exist or cannot be read.

Question 25

Files method, two overloaded copy methods.

Answer 25

Files.copy(InputStream is, Path p);

Files.cop(Path p, OutputStream s);

Question 26

Files method, moves or renames a file or directory within the file system.

Answer 26

Files.move(Path p, Path p) - throws IOException when the file or directory cannot be found.

Question 27

Files method, method deletes a file or empty directory within the file system.

Answer 27

Files.delete(Path p) throws the checked IOException under variety of circumstances.

Question 28

Files method, method is identical to the delete(Path) method, except that it will not throw an exception if the file or directory does not exist, but instead it will return a boolean value of false.

Answer 28

Files.deleteIfExists(Path p) throws

Question 29

Files method, writes to a file specified at the Path location using a BufferedWriter.

Answer 29

Files.newBufferedWriter(Path p, CharacterSet cs)

Question 30

Files method, reads the file specified at the Path location using a java.io.BufferedReader object

Answer 30

Files.newBufferedReader(Path p, CharacterSet cs)

Question 31

Files method, method reads all of the lines of a text file and returns the results as an ordered List of String values

Answer 31

Files.readAllLines()

Question 32

Files method, three methods for determining if a path refers to a directory, a regular file, or a symbolic link.

Answer 32

Files.isRegularFile(Path p), - true if path is a file or symbolic link to the file.

Files.isDirectory(Path p), - returns true if directory or symbolic link to directory.

Files.isSymbolicLink(Path p) - true if symbolic link

Question 33

Files method, method to determine whether a file or directory is hidden within the file system.

Answer 33

Files.isHidden(Path p)

Question 34

Files method, returns true if file exists and its contents are readable, based on the permission rules of the underlying file system.

Answer 34

Files.isReadable(Path p), does not throw exception if file does not exist but rather return false.

Question 35

Files method, returns true file is marked executable within the file system.

Answer 35

Files.isExecutable(Path p), does not throw exception if file does not exist but rather return false.

Question 36

Files method, method is used to determine the size of the file in bytes.

Answer 36

Files.size(Path p) throws IOException when the file does not exist

Question 37

Files method, returns a FileTime object, code reads and outputs the last-modified time value of

Answer 37

Files.getLastModifiedTime(Path p)

.toMillis() to get the epoch

Question 38

Files method, returns a FileTime object, set the last-modified time value of file

Answer 38

Files.setLastModifiedTime(Path p, FileTime ft)

Question 39

Files method, getting the owner and setting the owner

Answer 39

Files.setOwner(Path p, UserPrincipal owner)
Files.getOwner(Path p);

UserPrincipal owner = FileSystems.getDefault().getUserPrincipalLookUpService().lookUpPrincipal(“name”)

Question 40

Files method, returns a read-only view of the file attributes.

Answer 40

FIles.readAttributes(Path p, BasicFileAttributes.class) -> returns BasicFileAttribute

Question 41

Files method, returns the underlying attribute view, and it provides a direct resource for modifying file information.

Answer 41

Files.getFileAttributeView(Path, BasicFileAttributes.class)

Question 42

BasicFileAttributesView method for updating the time.

Answer 42

setTimes(FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime)

Question 43

Files method, method behaves in a similar manner as the Files.walk() method, except that it requires the depth value to be explicitly set along with a BiPredicate to filter the data.

Answer 43

Files.find(Path,int,BiPredicate) - > Stream

parameter depth and biPredicate(Path, BasicFileAttributes).