Package org.springframework.core.io

Class FileSystemResource

java.lang.Object

org.springframework.core.io.AbstractResource

org.springframework.core.io.FileSystemResource

All Implemented Interfaces:

InputStreamSource, Resource, WritableResource

public class FileSystemResource
extends AbstractResource
implements WritableResource

Resource implementation for java.io.File and java.nio.file.Path handles with a file system target. Supports resolution as a File and also as a URL. Implements the extended WritableResource interface.

Note: As of Spring Framework 5.0, this Resource implementation uses NIO.2 API for read/write interactions. As of 5.1, it may be constructed with a Path handle in which case it will perform all file system interactions via NIO.2, only resorting to File on getFile().

Since:

28.12.2003

Author:

Juergen Hoeller, Sam Brannen

See Also:

• FileSystemResource(String)
• FileSystemResource(File)
• FileSystemResource(Path)
• File
• Files

Constructor Summary

Constructors

Constructor	Description
FileSystemResource(File file)	Create a new FileSystemResource from a File handle.
FileSystemResource(String path)	Create a new FileSystemResource from a file path.
FileSystemResource(FileSystem fileSystem, String path)	Create a new FileSystemResource from a FileSystem handle, locating the specified path.
FileSystemResource(Path filePath)	Create a new FileSystemResource from a Path handle, performing all file system interactions via NIO.2 instead of File.

Method Summary

Modifier and Type	Method	Description
long	contentLength()	This implementation returns the underlying File/Path length.
Resource	createRelative(String relativePath)	This implementation creates a FileSystemResource, applying the given path relative to the path of the underlying file of this resource descriptor.
boolean	equals(Object other)	This implementation compares the underlying file paths.
boolean	exists()	This implementation returns whether the underlying file exists.
byte[]	getContentAsByteArray()	Return the contents of this resource as a byte array.
String	getContentAsString(Charset charset)	Return the contents of this resource as a string, using the specified charset.
String	getDescription()	This implementation returns a description that includes the absolute path of the file.
File	getFile()	This implementation returns the underlying File reference.
String	getFilename()	This implementation returns the name of the file.
InputStream	getInputStream()	This implementation opens an NIO file stream for the underlying file.
OutputStream	getOutputStream()	This implementation opens a FileOutputStream for the underlying file.
final String	getPath()	Return the file path for this resource.
URI	getURI()	This implementation returns a URI for the underlying file.
URL	getURL()	This implementation returns a URL for the underlying file.
int	hashCode()	This implementation returns the hash code of the underlying file path.
boolean	isFile()	This implementation always indicates a file.
boolean	isReadable()	This implementation checks whether the underlying file is marked as readable (and corresponds to an actual file with content, not to a directory).
boolean	isWritable()	This implementation checks whether the underlying file is marked as writable (and corresponds to an actual file with content, not to a directory).
long	lastModified()	This implementation returns the underlying File/Path last-modified time.
ReadableByteChannel	readableChannel()	This implementation opens a FileChannel for the underlying file.
WritableByteChannel	writableChannel()	This implementation opens a FileChannel for the underlying file.

Methods inherited from class org.springframework.core.io.AbstractResource

getFileForLastModifiedCheck, isOpen, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.springframework.core.io.Resource

isOpen

Constructor Details

FileSystemResource

public FileSystemResource(String path)

Create a new FileSystemResource from a file path.

Note: When building relative resources via createRelative(java.lang.String), it makes a difference whether the specified resource base path here ends with a slash or not. In the case of "C:/dir1/", relative paths will be built underneath that root: e.g. relative path "dir2" → "C:/dir1/dir2". In the case of "C:/dir1", relative paths will apply at the same directory level: relative path "dir2" → "C:/dir2".

Parameters:

path - a file path

See Also:

• FileSystemResource(Path)

FileSystemResource

public FileSystemResource(File file)

Create a new FileSystemResource from a File handle.

Note: When building relative resources via createRelative(java.lang.String), the relative path will apply at the same directory level: e.g. new File("C:/dir1"), relative path "dir2" → "C:/dir2"! If you prefer to have relative paths built underneath the given root directory, use the constructor with a file path to append a trailing slash to the root path: "C:/dir1/", which indicates this directory as root for all relative paths.

Parameters:

file - a File handle

See Also:

• FileSystemResource(Path)
• getFile()

FileSystemResource

public FileSystemResource(Path filePath)

Create a new FileSystemResource from a Path handle, performing all file system interactions via NIO.2 instead of File.

In contrast to PathResource, this variant strictly follows the general FileSystemResource conventions, in particular in terms of path cleaning and createRelative(String) handling.

Note: When building relative resources via createRelative(java.lang.String), the relative path will apply at the same directory level: e.g. Paths.get("C:/dir1"), relative path "dir2" → "C:/dir2"! If you prefer to have relative paths built underneath the given root directory, use the constructor with a file path to append a trailing slash to the root path: "C:/dir1/", which indicates this directory as root for all relative paths. Alternatively, consider using PathResource(Path) for java.nio.path.Path resolution in createRelative, always nesting relative paths.

Parameters:

filePath - a Path handle to a file

Since:

5.1

See Also:

• FileSystemResource(File)

FileSystemResource

public FileSystemResource(FileSystem fileSystem,
 String path)

Create a new FileSystemResource from a FileSystem handle, locating the specified path.

This is an alternative to FileSystemResource(String), performing all file system interactions via NIO.2 instead of File.

Parameters:

fileSystem - the FileSystem to locate the path within

path - a file path

Since:

5.1.1

See Also:

• FileSystemResource(File)

Method Details

getPath

public final String getPath()

Return the file path for this resource.

exists

public boolean exists()

This implementation returns whether the underlying file exists.

Specified by:

exists in interface Resource

Overrides:

exists in class AbstractResource

See Also:

• File.exists()
• Files.exists(Path, java.nio.file.LinkOption...)

isReadable

public boolean isReadable()

This implementation checks whether the underlying file is marked as readable (and corresponds to an actual file with content, not to a directory).

Specified by:

isReadable in interface Resource

Overrides:

isReadable in class AbstractResource

See Also:

• File.canRead()
• File.isDirectory()
• Files.isReadable(Path)
• Files.isDirectory(Path, java.nio.file.LinkOption...)

getInputStream

public InputStream getInputStream()
                           throws IOException

This implementation opens an NIO file stream for the underlying file.

Specified by:

getInputStream in interface InputStreamSource

Returns:

the input stream for the underlying resource (must not be null)

Throws:

FileNotFoundException - if the underlying resource does not exist

IOException - if the content stream could not be opened

See Also:

• Files.newInputStream(Path, java.nio.file.OpenOption...)

getContentAsByteArray

public byte[] getContentAsByteArray()
                             throws IOException

Description copied from interface: Resource

Return the contents of this resource as a byte array.

Specified by:

getContentAsByteArray in interface Resource

Returns:

the contents of this resource as byte array

Throws:

FileNotFoundException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

IOException - in case of general resolution/reading failures

getContentAsString

public String getContentAsString(Charset charset)
                          throws IOException

Description copied from interface: Resource

Return the contents of this resource as a string, using the specified charset.

Specified by:

getContentAsString in interface Resource

Parameters:

charset - the charset to use for decoding

Returns:

the contents of this resource as a String

Throws:

FileNotFoundException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

IOException - in case of general resolution/reading failures

isWritable

public boolean isWritable()

This implementation checks whether the underlying file is marked as writable (and corresponds to an actual file with content, not to a directory).

Specified by:

isWritable in interface WritableResource

See Also:

• File.canWrite()
• File.isDirectory()
• Files.isWritable(Path)
• Files.isDirectory(Path, java.nio.file.LinkOption...)

getOutputStream

public OutputStream getOutputStream()
                             throws IOException

This implementation opens a FileOutputStream for the underlying file.

Specified by:

getOutputStream in interface WritableResource

Throws:

IOException - if the stream could not be opened

See Also:

• Files.newOutputStream(Path, java.nio.file.OpenOption...)

getURL

public URL getURL()
           throws IOException

This implementation returns a URL for the underlying file.

Specified by:

getURL in interface Resource

Overrides:

getURL in class AbstractResource

Throws:

IOException - if the resource cannot be resolved as URL, i.e. if the resource is not available as a descriptor

See Also:

• File.toURI()
• Path.toUri()

getURI

public URI getURI()
           throws IOException

This implementation returns a URI for the underlying file.

Specified by:

getURI in interface Resource

Overrides:

getURI in class AbstractResource

Throws:

IOException - if the resource cannot be resolved as URI, i.e. if the resource is not available as a descriptor

See Also:

• File.toURI()
• Path.toUri()

isFile

public boolean isFile()

This implementation always indicates a file.

Specified by:

isFile in interface Resource

Overrides:

isFile in class AbstractResource

See Also:

• Resource.getFile()

getFile

public File getFile()

This implementation returns the underlying File reference.

Specified by:

getFile in interface Resource

Overrides:

getFile in class AbstractResource

See Also:

• InputStreamSource.getInputStream()

readableChannel

public ReadableByteChannel readableChannel()
                                    throws IOException

This implementation opens a FileChannel for the underlying file.

Specified by:

readableChannel in interface Resource

Overrides:

readableChannel in class AbstractResource

Returns:

the byte channel for the underlying resource (must not be null)

Throws:

FileNotFoundException - if the underlying resource doesn't exist

IOException - if the content channel could not be opened

See Also:

• FileChannel

writableChannel

public WritableByteChannel writableChannel()
                                    throws IOException

This implementation opens a FileChannel for the underlying file.

Specified by:

writableChannel in interface WritableResource

Returns:

the byte channel for the underlying resource (must not be null)

Throws:

FileNotFoundException - if the underlying resource doesn't exist

IOException - if the content channel could not be opened

See Also:

• FileChannel

contentLength

public long contentLength()
                   throws IOException

This implementation returns the underlying File/Path length.

Specified by:

contentLength in interface Resource

Overrides:

contentLength in class AbstractResource

Throws:

IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

See Also:

• InputStreamSource.getInputStream()

lastModified

public long lastModified()
                  throws IOException

This implementation returns the underlying File/Path last-modified time.

Specified by:

lastModified in interface Resource

Overrides:

lastModified in class AbstractResource

Throws:

IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

See Also:

• AbstractResource.getFileForLastModifiedCheck()

createRelative

public Resource createRelative(String relativePath)

This implementation creates a FileSystemResource, applying the given path relative to the path of the underlying file of this resource descriptor.

Specified by:

createRelative in interface Resource

Overrides:

createRelative in class AbstractResource

Parameters:

relativePath - the relative path (relative to this resource)

Returns:

the resource handle for the relative resource

See Also:

• StringUtils.applyRelativePath(String, String)

getFilename

public String getFilename()

This implementation returns the name of the file.

Specified by:

getFilename in interface Resource

Overrides:

getFilename in class AbstractResource

See Also:

• File.getName()
• Path.getFileName()

getDescription

public String getDescription()

This implementation returns a description that includes the absolute path of the file.

Specified by:

getDescription in interface Resource

See Also:

• File.getAbsolutePath()
• Path.toAbsolutePath()

equals

public boolean equals(@Nullable
 Object other)

This implementation compares the underlying file paths.

Overrides:

equals in class AbstractResource

See Also:

• getPath()

hashCode

public int hashCode()

This implementation returns the hash code of the underlying file path.

Overrides:

hashCode in class AbstractResource

See Also:

• getPath()