BasicFileAttributeView
public
interface
BasicFileAttributeView
implements
FileAttributeView
| java.nio.file.attribute.BasicFileAttributeView |
A file attribute view that provides a view of a basic set of file
attributes common to many file systems. The basic set of file attributes
consist of mandatory and optional file attributes as
defined by the BasicFileAttributes interface.
The file attributes are retrieved from the file system as a bulk
operation by invoking the readAttributes method.
This class also defines the setTimes method to update the
file's time attributes.
Where dynamic access to file attributes is required, the attributes supported by this attribute view have the following names and types:
Name Type "lastModifiedTime" FileTime"lastAccessTime" FileTime"creationTime" FileTime"size" Long"isRegularFile" Boolean"isDirectory" Boolean"isSymbolicLink" Boolean"isOther" Boolean"fileKey" Object
The getAttribute method may be
used to read any of these attributes as if by invoking the readAttributes() method.
The setAttribute method may be
used to update the file's last modified time, last access time or create time
attributes as if by invoking the setTimes method.
Summary
Public methods | |
|---|---|
abstract
String
|
name()
Returns the name of the attribute view. |
abstract
BasicFileAttributes
|
readAttributes()
Reads the basic file attributes as a bulk operation. |
abstract
void
|
setTimes(FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime)
Updates any or all of the file's last modified time, last access time, and create time attributes. |
Inherited methods | |
|---|---|
Public methods
name
public abstract String name ()
Returns the name of the attribute view. Attribute views of this type
have the name "basic".
| Returns | |
|---|---|
String |
the name of the attribute view |
readAttributes
public abstract BasicFileAttributes readAttributes ()
Reads the basic file attributes as a bulk operation.
It is implementation specific if all file attributes are read as an atomic operation with respect to other file system operations.
| Returns | |
|---|---|
BasicFileAttributes |
the file attributes |
| Throws | |
|---|---|
IOException |
if an I/O error occurs |
SecurityException |
In the case of the default provider, a security manager is
installed, its checkRead
method is invoked to check read access to the file |
setTimes
public abstract void setTimes (FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime)
Updates any or all of the file's last modified time, last access time, and create time attributes.
This method updates the file's timestamp attributes. The values are
converted to the epoch and precision supported by the file system.
Converting from finer to coarser granularities result in precision loss.
The behavior of this method when attempting to set a timestamp that is
not supported or to a value that is outside the range supported by the
underlying file store is not defined. It may or not fail by throwing an
IOException.
If any of the lastModifiedTime, lastAccessTime,
or createTime parameters has the value null then the
corresponding timestamp is not changed. An implementation may require to
read the existing values of the file attributes when only some, but not
all, of the timestamp attributes are updated. Consequently, this method
may not be an atomic operation with respect to other file system
operations. Reading and re-writing existing values may also result in
precision loss. If all of the lastModifiedTime, lastAccessTime and createTime parameters are null then
this method has no effect.
Usage Example: Suppose we want to change a file's last access time.
Path path = ...
FileTime time = ...
Files.getFileAttributeView(path, BasicFileAttributeView.class).setTimes(null, time, null);
| Parameters | |
|---|---|
lastModifiedTime |
FileTime: the new last modified time, or null to not change the
value |
lastAccessTime |
FileTime: the last access time, or null to not change the value |
createTime |
FileTime: the file's create time, or null to not change the value |
| Throws | |
|---|---|
IOException |
if an I/O error occurs |
SecurityException |
In the case of the default provider, a security manager is
installed, its checkWrite
method is invoked to check write access to the file |