Package com.google.common.io

Class MoreFiles

com.google.common.io.MoreFiles

@Beta
@GwtIncompatible
public final class MoreFiles
extends 

Static utilities for use with instances, intended to complement .

Many methods provided by Guava's Files class for instances are now available via the JDK's class for Path - check the JDK's class if a sibling method from Files appears to be missing from this class.

Since:

21.0

Author:

Colin Decker

Method Summary

Modifier and Type	Method	Description
static ByteSink	path, ... options)	Returns a view of the given path as a ByteSink.
static ByteSource	path, ... options)	Returns a view of the given path as a ByteSource.
static CharSink	path, charset, ... options)	Returns a view of the given path as a CharSink using the given charset.
static CharSource	path, charset, ... options)	Returns a view of the given path as a CharSource using the given charset.
static void	path, <?>... attrs)	Creates any necessary but nonexistent parent directories of the specified path.
static void	path, RecursiveDeleteOption... options)	Deletes all files within the directory at the given path recursively.
static void	path, RecursiveDeleteOption... options)	Deletes the file or directory at the given path recursively.
static boolean	path1, path2)	Returns true if the files located by the given paths exist, are not directories, and contain the same bytes.
static >	fileTraverser()	Returns a Traverser instance for the file and directory tree.
static	path)	Returns the for the file at the given path, or the empty string if the file has no extension.
static	path)	Returns the file name without its or path.
static >	... options)	Returns a predicate that returns the result of on input paths with the given link options.
static >	... options)	Returns a predicate that returns the result of on input paths with the given link options.
static >	dir)	Returns an immutable list of paths to the files contained in the given directory.
static void	path)	Like the unix command of the same name, creates an empty file or updates the last modified timestamp of the existing file at the given path to the current system time.

Methods inherited from class java.lang.

, , , , , , , , , ,

Method Detail

asByteSource

public static  path,
                                      ... options)

Returns a view of the given path as a ByteSource.

Any provided are used when opening streams to the file and may affect the behavior of the returned source and the streams it provides. See for the standard options that may be provided. Providing no options is equivalent to providing the option.

asByteSink

public static  path,
                                  ... options)

Returns a view of the given path as a ByteSink.

Any provided are used when opening streams to the file and may affect the behavior of the returned sink and the streams it provides. See for the standard options that may be provided. Providing no options is equivalent to providing the , and options.

asCharSource

public static  path,
                                       charset,
                                      ... options)

Returns a view of the given path as a CharSource using the given charset.

Any provided are used when opening streams to the file and may affect the behavior of the returned source and the streams it provides. See for the standard options that may be provided. Providing no options is equivalent to providing the option.

asCharSink

public static  path,
                                   charset,
                                  ... options)

Returns a view of the given path as a CharSink using the given charset.

Any provided are used when opening streams to the file and may affect the behavior of the returned sink and the streams it provides. See for the standard options that may be provided. Providing no options is equivalent to providing the , and options.

listFiles

public static >  dir)
                                     throws 

Returns an immutable list of paths to the files contained in the given directory.

Throws:

- if the file does not exist (optional specific exception)

- if the file could not be opened because it is not a directory (optional specific exception)

- if an I/O error occurs

fileTraverser

public static > fileTraverser()

Returns a Traverser instance for the file and directory tree. The returned traverser starts from a and will return all files and directories it encounters.

The returned traverser attempts to avoid following symbolic links to directories. However, the traverser cannot guarantee that it will not follow symbolic links to directories as it is possible for a directory to be replaced with a symbolic link between checking if the file is a directory and actually reading the contents of that directory.

If the passed to one of the traversal methods does not exist or is not a directory, no exception will be thrown and the returned will contain a single element: that path.

may be thrown when iterating instances created by this traverser if an is thrown by a call to listFiles(Path).

Example: MoreFiles.fileTraverser().depthFirstPreOrder(Paths.get("/")) may return the following paths: ["/", "/etc", "/etc/config.txt", "/etc/fonts", "/home", "/home/alice", ...]

Since:

23.5

isDirectory

public static > ... options)

Returns a predicate that returns the result of on input paths with the given link options.

isRegularFile

public static > ... options)

Returns a predicate that returns the result of on input paths with the given link options.

equal

public static boolean  path1,
                             path2)
                     throws 

Returns true if the files located by the given paths exist, are not directories, and contain the same bytes.

Throws:

- if an I/O error occurs

Since:

22.0

touch

public static void  path)
                  throws 

Like the unix command of the same name, creates an empty file or updates the last modified timestamp of the existing file at the given path to the current system time.

Throws:

createParentDirectories

public static void  path,
                                           <?>... attrs)
                                    throws 

Creates any necessary but nonexistent parent directories of the specified path. Note that if this operation fails, it may have succeeded in creating some (but not all) of the necessary parent directories. The parent directory is created with the given attrs.

Throws:

- if an I/O error occurs, or if any necessary but nonexistent parent directories of the specified file could not be created.

getFileExtension

public static   path)

Returns the for the file at the given path, or the empty string if the file has no extension. The result does not include the '.'.

Note: This method simply returns everything after the last '.' in the file's name as determined by . It does not account for any filesystem-specific behavior that the API does not already account for. For example, on NTFS it will report "txt" as the extension for the filename "foo.exe:.txt" even though NTFS will drop the ":.txt" part of the name when the file is actually created on the filesystem due to NTFS's .

getNameWithoutExtension

public static   path)

Returns the file name without its or path. This is similar to the basename unix command. The result does not include the '.'.

deleteRecursively

public static void  path,
                                     RecursiveDeleteOption... options)
                              throws 

Deletes the file or directory at the given path recursively. Deletes symbolic links, not their targets (subject to the caveat below).

If an I/O exception occurs attempting to read, open or delete any file under the given directory, this method skips that file and continues. All such exceptions are collected and, after attempting to delete all files, an IOException is thrown containing those exceptions as .

Warning: Security of recursive deletes

On a file system that supports symbolic links and does not support , it is possible for a recursive delete to delete files and directories that are outside the directory being deleted. This can happen if, after checking that a file is a directory (and not a symbolic link), that directory is replaced by a symbolic link to an outside directory before the call that opens the directory to read its entries.

By default, this method throws InsecureRecursiveDeleteException if it can't guarantee the security of recursive deletes. If you wish to allow the recursive deletes anyway, pass RecursiveDeleteOption.ALLOW_INSECURE to this method to override that behavior.

Throws:

- if path does not exist (optional specific exception)

InsecureRecursiveDeleteException - if the security of recursive deletes can't be guaranteed for the file system and RecursiveDeleteOption.ALLOW_INSECURE was not specified

- if path or any file in the subtree rooted at it can't be deleted for any reason

deleteDirectoryContents

public static void  path,
                                           RecursiveDeleteOption... options)
                                    throws 

Deletes all files within the directory at the given path recursively. Does not delete the directory itself. Deletes symbolic links, not their targets (subject to the caveat below). If path itself is a symbolic link to a directory, that link is followed and the contents of the directory it targets are deleted.

If an I/O exception occurs attempting to read, open or delete any file under the given directory, this method skips that file and continues. All such exceptions are collected and, after attempting to delete all files, an IOException is thrown containing those exceptions as .

Warning: Security of recursive deletes

On a file system that supports symbolic links and does not support , it is possible for a recursive delete to delete files and directories that are outside the directory being deleted. This can happen if, after checking that a file is a directory (and not a symbolic link), that directory is replaced by a symbolic link to an outside directory before the call that opens the directory to read its entries.

By default, this method throws InsecureRecursiveDeleteException if it can't guarantee the security of recursive deletes. If you wish to allow the recursive deletes anyway, pass RecursiveDeleteOption.ALLOW_INSECURE to this method to override that behavior.

Throws:

- if path does not exist (optional specific exception)

- if the file at path is not a directory (optional specific exception)

InsecureRecursiveDeleteException - if the security of recursive deletes can't be guaranteed for the file system and RecursiveDeleteOption.ALLOW_INSECURE was not specified

- if one or more files can't be deleted for any reason