Java: Interface BasicFileAttributeView
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All Superinterfaces:
AttributeView, FileAttributeView
All Known Subinterfaces:
DosFileAttributeView, PosixFileAttributeView
public interface BasicFileAttributeView extends FileAttributeView
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.
Since:
1.7
Method Summary
Modifier and Type | Method and Description |
---|---|
String |
Returns the name of the attribute view.
|
BasicFileAttributes |
Reads the basic file attributes as a bulk operation.
|
void |
Updates any or all of the file's last modified time, last access time, and create time attributes.
|
Method Detail
name
String name()
"basic"
.Specified by:
name
in interface AttributeView
Returns:
the name of the attribute view
readAttributes
BasicFileAttributes readAttributes() throws IOException
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:
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
void setTimes(FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime) throws IOException
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 thelastModifiedTime, 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
- the new last modified time, or null
to not change the value
lastAccessTime
- the last access time, or null
to not change the value
createTime
- 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 checkWritemethod is invoked to check write access to the file
See Also:
Files.setLastModifiedTime(java.nio.file.Path, java.nio.file.attribute.FileTime)
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