New Input/Output 2 - Beginning Java 8 Language Features - page 454

file attributes, you have the BasicFileAttributes and BasicFileAtrributeView interfaces. The XxxAttributes
lets you read the attributes. The XxxAttributeView lets you read as well as update the attributes. If you only want to
read the attributes, use XxxAttributes . If you want to read and update attributes, use XxxAttributeView as well as
XxxAttributes .
The following two methods of the Files class let you read the file attributes in a bulk, which is much more
efficient than reading one attribute at a time.

•

<A extends BasicFileAttributes> A readAttributes(Path path, Class<A> type,
LinkOption... options)

Map<String,Object> readAttributes(Path path, String attributes, LinkOption...
options)
The last argument of both methods lets you specify how a symbolic link is handled. By default, if a file is a
symbolic link, the attributes of the target of the symbolic link are read. If you specify NOFOLLOW_LINKS as the option,
the attributes of the symbolic link are read, not the attributes of its target.
The first readAttributes() method returns all file attributes of a specified type in an XxxAttributes object.
For example, you would write the following snippet of code to read the basic file attributes:

•

// Create the Path object representing the path of the file
Path path = Paths.get("C:\\poems\\luci1.txt");

// Read the basic file attributes
BasicFileAttributes bfa =
Files.readAttributes(path, BasicFileAttributes.class);

// Get the last modified time
FileTime lastModifiedTime = bfa.lastModifiedTime();

// Get the size of the file
long size = bfa.size();

The second readAttributes() method returns all or some of the attributes of a specific type. The list of attributes
to read is supplied in a string form. The string form of an attribute list uses the following syntax:

view-name:comma-separated-attributes

The view-name is the name of the attribute view that you want to read, such as basic , posix , acl , etc.
If view-name is omitted, it defaults to basic . If view-name is present, it is followed by a colon. You can read all
attributes of a specific view type by specifying an asterisk as the attributes list. For example, you can specify "basic:*"
or "*" to read all basic file attributes. To read the size and the last modified time of the basic view, you would use
"basic:size,lastModifiedTime" or "size,lastModifiedTime" . To read the owner attribute of a file using an
ACL view, you would use a string "acl:owner" . To read all posix attributes of a file, you would use "posix:*" .
The following snippet of code prints the size and the last modified time of the file C:\poems\luci1.txt . Note that
the file path uses Windows syntax.

// Get a Path object
Path path = Paths.get("C:\\poems\\luci1.txt");

// Prepare the attribute list
String attribList = "basic:size,lastModifiedTime";