@Beta @GwtIncompatible public final class Files extends java.lang.Object
Path
users will find similar utilities in MoreFiles
and the
JDK's Files
class.
Modifier and Type | Method and Description |
---|---|
static void |
append(java.lang.CharSequence from,
java.io.File to,
java.nio.charset.Charset charset)
Deprecated.
Prefer
asCharSink(to, charset, FileWriteMode.APPEND).write(from) . This
method is scheduled to be removed in January 2019. |
static ByteSink |
asByteSink(java.io.File file,
FileWriteMode... modes)
Returns a new
ByteSink for writing bytes to the given file. |
static ByteSource |
asByteSource(java.io.File file)
Returns a new
ByteSource for reading bytes from the given file. |
static CharSink |
asCharSink(java.io.File file,
java.nio.charset.Charset charset,
FileWriteMode... modes)
Returns a new
CharSink for writing character data to the given file using the given
character set. |
static CharSource |
asCharSource(java.io.File file,
java.nio.charset.Charset charset)
Returns a new
CharSource for reading character data from the given file using the given
character set. |
static void |
copy(java.io.File from,
java.nio.charset.Charset charset,
java.lang.Appendable to)
Deprecated.
Prefer
asCharSource(from, charset).copyTo(to) . This method is scheduled to
be removed in January 2019. |
static void |
copy(java.io.File from,
java.io.File to)
Copies all the bytes from one file to another.
|
static void |
copy(java.io.File from,
java.io.OutputStream to)
Copies all bytes from a file to an output stream.
|
static void |
createParentDirs(java.io.File file)
Creates any necessary but nonexistent parent directories of the specified file.
|
static java.io.File |
createTempDir()
Atomically creates a new directory somewhere beneath the system's temporary directory (as
defined by the
java.io.tmpdir system property), and returns its name. |
static boolean |
equal(java.io.File file1,
java.io.File file2)
Returns true if the given files exist, are not directories, and contain the same bytes.
|
static Traverser<java.io.File> |
fileTraverser()
Returns a
Traverser instance for the file and directory tree. |
static java.lang.String |
getFileExtension(java.lang.String fullName)
Returns the file extension for
the given file name, or the empty string if the file has no extension.
|
static java.lang.String |
getNameWithoutExtension(java.lang.String file)
Returns the file name without its file extension or path.
|
static HashCode |
hash(java.io.File file,
HashFunction hashFunction)
Deprecated.
Prefer
asByteSource(file).hash(hashFunction) . This method is scheduled to
be removed in January 2019. |
static Predicate<java.io.File> |
isDirectory()
Returns a predicate that returns the result of
File.isDirectory() on input files. |
static Predicate<java.io.File> |
isFile()
Returns a predicate that returns the result of
File.isFile() on input files. |
static java.nio.MappedByteBuffer |
map(java.io.File file)
Fully maps a file read-only in to memory as per
FileChannel.map(java.nio.channels.FileChannel.MapMode, long, long) . |
static java.nio.MappedByteBuffer |
map(java.io.File file,
java.nio.channels.FileChannel.MapMode mode)
Fully maps a file in to memory as per
FileChannel.map(java.nio.channels.FileChannel.MapMode, long, long) using the requested FileChannel.MapMode . |
static java.nio.MappedByteBuffer |
map(java.io.File file,
java.nio.channels.FileChannel.MapMode mode,
long size)
Maps a file in to memory as per
FileChannel.map(java.nio.channels.FileChannel.MapMode,
long, long) using the requested FileChannel.MapMode . |
static void |
move(java.io.File from,
java.io.File to)
Moves a file from one path to another.
|
static java.io.BufferedReader |
newReader(java.io.File file,
java.nio.charset.Charset charset)
Returns a buffered reader that reads from a file using the given character set.
|
static java.io.BufferedWriter |
newWriter(java.io.File file,
java.nio.charset.Charset charset)
Returns a buffered writer that writes to a file using the given character set.
|
static <T> T |
readBytes(java.io.File file,
ByteProcessor<T> processor)
Deprecated.
Prefer
asByteSource(file).read(processor) . This method is scheduled to be
removed in January 2019. |
static java.lang.String |
readFirstLine(java.io.File file,
java.nio.charset.Charset charset)
Deprecated.
Prefer
asCharSource(file, charset).readFirstLine() . This method is
scheduled to be removed in January 2019. |
static java.util.List<java.lang.String> |
readLines(java.io.File file,
java.nio.charset.Charset charset)
Reads all of the lines from a file.
|
static <T> T |
readLines(java.io.File file,
java.nio.charset.Charset charset,
LineProcessor<T> callback)
Deprecated.
Prefer
asCharSource(file, charset).readLines(callback) . This method is
scheduled to be removed in January 2019. |
static java.lang.String |
simplifyPath(java.lang.String pathname)
Returns the lexically cleaned form of the path name, usually (but not always) equivalent
to the original.
|
static byte[] |
toByteArray(java.io.File file)
Reads all bytes from a file into a byte array.
|
static java.lang.String |
toString(java.io.File file,
java.nio.charset.Charset charset)
Deprecated.
Prefer
asCharSource(file, charset).read() . This method is scheduled to be
removed in January 2019. |
static void |
touch(java.io.File file)
Creates an empty file or updates the last updated timestamp on the same as the unix command of
the same name.
|
static void |
write(byte[] from,
java.io.File to)
Overwrites a file with the contents of a byte array.
|
static void |
write(java.lang.CharSequence from,
java.io.File to,
java.nio.charset.Charset charset)
Deprecated.
Prefer
asCharSink(to, charset).write(from) . This method is scheduled to be
removed in January 2019. |
public static java.io.BufferedReader newReader(java.io.File file, java.nio.charset.Charset charset) throws java.io.FileNotFoundException
Path
equivalent: Files.newBufferedReader(java.nio.file.Path, Charset)
.
file
- the file to read fromcharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantsjava.io.FileNotFoundException
public static java.io.BufferedWriter newWriter(java.io.File file, java.nio.charset.Charset charset) throws java.io.FileNotFoundException
Path
equivalent: Files.newBufferedWriter(java.nio.file.Path, Charset,
java.nio.file.OpenOption...)
.
file
- the file to write tocharset
- the charset used to encode the output stream; see StandardCharsets
for
helpful predefined constantsjava.io.FileNotFoundException
public static ByteSource asByteSource(java.io.File file)
ByteSource
for reading bytes from the given file.public static ByteSink asByteSink(java.io.File file, FileWriteMode... modes)
ByteSink
for writing bytes to the given file. The given modes
control how the file is opened for writing. When no mode is provided, the file will be
truncated before writing. When the APPEND
mode is provided, writes
will append to the end of the file without truncating it.public static CharSource asCharSource(java.io.File file, java.nio.charset.Charset charset)
CharSource
for reading character data from the given file using the given
character set.public static CharSink asCharSink(java.io.File file, java.nio.charset.Charset charset, FileWriteMode... modes)
CharSink
for writing character data to the given file using the given
character set. The given modes
control how the file is opened for writing. When no mode
is provided, the file will be truncated before writing. When the APPEND
mode is provided, writes will append to the end of the file without truncating it.public static byte[] toByteArray(java.io.File file) throws java.io.IOException
Path
equivalent: Files.readAllBytes(java.nio.file.Path)
.
file
- the file to read fromjava.lang.IllegalArgumentException
- if the file is bigger than the largest possible byte array
(2^31 - 1)java.io.IOException
- if an I/O error occurs@Deprecated public static java.lang.String toString(java.io.File file, java.nio.charset.Charset charset) throws java.io.IOException
asCharSource(file, charset).read()
. This method is scheduled to be
removed in January 2019.String
, using the given character set.file
- the file to read fromcharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantsjava.io.IOException
- if an I/O error occurspublic static void write(byte[] from, java.io.File to) throws java.io.IOException
Path
equivalent: Files.write(java.nio.file.Path, byte[], java.nio.file.OpenOption...)
.
from
- the bytes to writeto
- the destination filejava.io.IOException
- if an I/O error occurs@Deprecated public static void write(java.lang.CharSequence from, java.io.File to, java.nio.charset.Charset charset) throws java.io.IOException
asCharSink(to, charset).write(from)
. This method is scheduled to be
removed in January 2019.from
- the character sequence to writeto
- the destination filecharset
- the charset used to encode the output stream; see StandardCharsets
for
helpful predefined constantsjava.io.IOException
- if an I/O error occurspublic static void copy(java.io.File from, java.io.OutputStream to) throws java.io.IOException
Path
equivalent: Files.copy(java.nio.file.Path, OutputStream)
.
from
- the source fileto
- the output streamjava.io.IOException
- if an I/O error occurspublic static void copy(java.io.File from, java.io.File to) throws java.io.IOException
Copying is not an atomic operation - in the case of an I/O error, power loss, process
termination, or other problems, to
may not be a complete copy of from
. If you
need to guard against those conditions, you should employ other file-level synchronization.
Warning: If to
represents an existing file, that file will be overwritten
with the contents of from
. If to
and from
refer to the same
file, the contents of that file will be deleted.
Path
equivalent: Files.copy(java.nio.file.Path, java.nio.file.Path, java.nio.file.CopyOption...)
.
from
- the source fileto
- the destination filejava.io.IOException
- if an I/O error occursjava.lang.IllegalArgumentException
- if from.equals(to)
@Deprecated public static void copy(java.io.File from, java.nio.charset.Charset charset, java.lang.Appendable to) throws java.io.IOException
asCharSource(from, charset).copyTo(to)
. This method is scheduled to
be removed in January 2019.from
- the source filecharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantsto
- the appendable objectjava.io.IOException
- if an I/O error occurs@Deprecated public static void append(java.lang.CharSequence from, java.io.File to, java.nio.charset.Charset charset) throws java.io.IOException
asCharSink(to, charset, FileWriteMode.APPEND).write(from)
. This
method is scheduled to be removed in January 2019.from
- the character sequence to appendto
- the destination filecharset
- the charset used to encode the output stream; see StandardCharsets
for
helpful predefined constantsjava.io.IOException
- if an I/O error occurspublic static boolean equal(java.io.File file1, java.io.File file2) throws java.io.IOException
java.io.IOException
- if an I/O error occurspublic static java.io.File createTempDir()
java.io.tmpdir
system property), and returns its name.
Use this method instead of File.createTempFile(String, String)
when you wish to
create a directory, not a regular file. A common pitfall is to call createTempFile
,
delete the file and create a directory in its place, but this leads a race condition which can
be exploited to create security vulnerabilities, especially when executable files are to be
written into the directory.
This method assumes that the temporary volume is writable, has free inodes and free blocks, and that it will not be called thousands of times per second.
Path
equivalent: Files.createTempDirectory(java.nio.file.Path, java.lang.String, java.nio.file.attribute.FileAttribute<?>...)
.
java.lang.IllegalStateException
- if the directory could not be createdpublic static void touch(java.io.File file) throws java.io.IOException
file
- the file to create or updatejava.io.IOException
- if an I/O error occurspublic static void createParentDirs(java.io.File file) throws java.io.IOException
java.io.IOException
- if an I/O error occurs, or if any necessary but nonexistent parent
directories of the specified file could not be created.public static void move(java.io.File from, java.io.File to) throws java.io.IOException
to
must be the target path for the file itself; not
just the new name for the file or the path to the new parent directory.
Path
equivalent: Files.move(java.nio.file.Path, java.nio.file.Path, java.nio.file.CopyOption...)
.
from
- the source fileto
- the destination filejava.io.IOException
- if an I/O error occursjava.lang.IllegalArgumentException
- if from.equals(to)
@Deprecated public static java.lang.String readFirstLine(java.io.File file, java.nio.charset.Charset charset) throws java.io.IOException
asCharSource(file, charset).readFirstLine()
. This method is
scheduled to be removed in January 2019.file
- the file to read fromcharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantsjava.io.IOException
- if an I/O error occurspublic static java.util.List<java.lang.String> readLines(java.io.File file, java.nio.charset.Charset charset) throws java.io.IOException
This method returns a mutable List
. For an ImmutableList
, use Files.asCharSource(file, charset).readLines()
.
Path
equivalent: Files.readAllLines(java.nio.file.Path, Charset)
.
file
- the file to read fromcharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantsList
containing all the linesjava.io.IOException
- if an I/O error occurs@Deprecated @CanIgnoreReturnValue public static <T> T readLines(java.io.File file, java.nio.charset.Charset charset, LineProcessor<T> callback) throws java.io.IOException
asCharSource(file, charset).readLines(callback)
. This method is
scheduled to be removed in January 2019.File
, stopping when our callback returns false, or we have read
all of the lines.file
- the file to read fromcharset
- the charset used to decode the input stream; see StandardCharsets
for
helpful predefined constantscallback
- the LineProcessor
to use to handle the linesjava.io.IOException
- if an I/O error occurs@Deprecated @CanIgnoreReturnValue public static <T> T readBytes(java.io.File file, ByteProcessor<T> processor) throws java.io.IOException
asByteSource(file).read(processor)
. This method is scheduled to be
removed in January 2019.(If this seems too complicated, maybe you're looking for toByteArray(java.io.File)
.)
file
- the file to readprocessor
- the object to which the bytes of the file are passed.java.io.IOException
- if an I/O error occurs@Deprecated public static HashCode hash(java.io.File file, HashFunction hashFunction) throws java.io.IOException
asByteSource(file).hash(hashFunction)
. This method is scheduled to
be removed in January 2019.file
using hashFunction
.file
- the file to readhashFunction
- the hash function to use to hash the dataHashCode
of all of the bytes in the filejava.io.IOException
- if an I/O error occurspublic static java.nio.MappedByteBuffer map(java.io.File file) throws java.io.IOException
FileChannel.map(java.nio.channels.FileChannel.MapMode, long, long)
.
Files are mapped from offset 0 to its length.
This only works for files ≤ Integer.MAX_VALUE
bytes.
file
- the file to mapfile
java.io.FileNotFoundException
- if the file
does not existjava.io.IOException
- if an I/O error occursFileChannel.map(MapMode, long, long)
public static java.nio.MappedByteBuffer map(java.io.File file, java.nio.channels.FileChannel.MapMode mode) throws java.io.IOException
FileChannel.map(java.nio.channels.FileChannel.MapMode, long, long)
using the requested FileChannel.MapMode
.
Files are mapped from offset 0 to its length.
This only works for files ≤ Integer.MAX_VALUE
bytes.
file
- the file to mapmode
- the mode to use when mapping file
file
java.io.FileNotFoundException
- if the file
does not existjava.io.IOException
- if an I/O error occursFileChannel.map(MapMode, long, long)
public static java.nio.MappedByteBuffer map(java.io.File file, java.nio.channels.FileChannel.MapMode mode, long size) throws java.io.FileNotFoundException, java.io.IOException
FileChannel.map(java.nio.channels.FileChannel.MapMode,
long, long)
using the requested FileChannel.MapMode
.
Files are mapped from offset 0 to size
.
If the mode is FileChannel.MapMode.READ_WRITE
and the file does not exist, it will be created
with the requested size
. Thus this method is useful for creating memory mapped files
which do not yet exist.
This only works for files ≤ Integer.MAX_VALUE
bytes.
file
- the file to mapmode
- the mode to use when mapping file
file
java.io.IOException
- if an I/O error occursjava.io.FileNotFoundException
FileChannel.map(MapMode, long, long)
public static java.lang.String simplifyPath(java.lang.String pathname)
These heuristics do not always match the behavior of the filesystem. In particular, consider
the path a/../b
, which simplifyPath
will change to b
. If a
is a
symlink to x
, a/../b
may refer to a sibling of x
, rather than the
sibling of a
referred to by b
.
public static java.lang.String getFileExtension(java.lang.String fullName)
.
'.
Note: This method simply returns everything after the last '.
' in the file's
name as determined by File.getName()
. It does not account for any filesystem-specific
behavior that the File
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 Alternate Data Streams.
public static java.lang.String getNameWithoutExtension(java.lang.String file)
basename
unix command. The result does not include the '.
'.file
- The name of the file to trim the extension from. This can be either a fully
qualified file name (including a path) or just a file name.public static Traverser<java.io.File> fileTraverser()
Traverser
instance for the file and directory tree. The returned traverser
starts from a File
and will return all files and directories it encounters.
Warning: File
provides no support for symbolic links, and as such there is no
way to ensure that a symbolic link to a directory is not followed when traversing the tree. In
this case, iterables created by this traverser could contain files that are outside of the
given directory or even be infinite if there is a symbolic link loop.
If available, consider using MoreFiles.fileTraverser()
instead. It behaves the same
except that it doesn't follow symbolic links and returns Path
instances.
If the File
passed to one of the Traverser
methods does not exist or is not
a directory, no exception will be thrown and the returned Iterable
will contain a
single element: that file.
Example: Files.fileTraverser().breadthFirst("/")
may return files with the following
paths: ["/", "/etc", "/home", "/usr", "/etc/config.txt", "/etc/fonts", ...]
public static Predicate<java.io.File> isDirectory()
File.isDirectory()
on input files.Copyright © 2010–2020 JBoss by Red Hat. All rights reserved.