public enum StandardOpenOption extends Enum<StandardOpenOption> implements OpenOption
Defines the standard open options.
public static final StandardOpenOption READ
Open for read access.
public static final StandardOpenOption WRITE
Open for write access.
public static final StandardOpenOption APPEND
If the file is opened for WRITE
access then bytes will be written to the end of the file rather than the beginning.
If the file is opened for write access by other programs, then it is file system specific if writing to the end of the file is atomic.
public static final StandardOpenOption TRUNCATE_EXISTING
If the file already exists and it is opened for WRITE
access, then its length is truncated to 0. This option is ignored if the file is opened only for READ
access.
public static final StandardOpenOption CREATE
Create a new file if it does not exist. This option is ignored if the CREATE_NEW
option is also set. The check for the existence of the file and the creation of the file if it does not exist is atomic with respect to other file system operations.
public static final StandardOpenOption CREATE_NEW
Create a new file, failing if the file already exists. The check for the existence of the file and the creation of the file if it does not exist is atomic with respect to other file system operations.
public static final StandardOpenOption DELETE_ON_CLOSE
Delete on close. When this option is present then the implementation makes a best effort attempt to delete the file when closed by the appropriate close
method. If the close
method is not invoked then a best effort attempt is made to delete the file when the Java virtual machine terminates (either normally, as defined by the Java Language Specification, or where possible, abnormally). This option is primarily intended for use with work files that are used solely by a single instance of the Java virtual machine. This option is not recommended for use when opening files that are open concurrently by other entities. Many of the details as to when and how the file is deleted are implementation specific and therefore not specified. In particular, an implementation may be unable to guarantee that it deletes the expected file when replaced by an attacker while the file is open. Consequently, security sensitive applications should take care when using this option.
For security reasons, this option may imply the LinkOption.NOFOLLOW_LINKS
option. In other words, if the option is present when opening an existing file that is a symbolic link then it may fail (by throwing IOException
).
public static final StandardOpenOption SPARSE
Sparse file. When used with the CREATE_NEW
option then this option provides a hint that the new file will be sparse. The option is ignored when the file system does not support the creation of sparse files.
public static final StandardOpenOption SYNC
Requires that every update to the file's content or metadata be written synchronously to the underlying storage device.
public static final StandardOpenOption DSYNC
Requires that every update to the file's content be written synchronously to the underlying storage device.
public static StandardOpenOption[] values()
Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
for (StandardOpenOption c : StandardOpenOption.values()) System.out.println(c);
public static StandardOpenOption valueOf(String name)
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
name
- the name of the enum constant to be returned.IllegalArgumentException
- if this enum type has no constant with the specified nameNullPointerException
- if the argument is null
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