Interface Resource
- All Superinterfaces:
InputStreamSource
- All Known Subinterfaces:
ContextResource
,HttpResource
,HttpResource
,WritableResource
- All Known Implementing Classes:
AbstractFileResolvingResource
,AbstractResource
,ByteArrayResource
,ClassPathResource
,DefaultResourceLoader.ClassPathContextResource
,DescriptiveResource
,FileSystemResource
,FileUrlResource
,InputStreamResource
,PathResource
,ServletContextResource
,TransformedResource
,TransformedResource
,UrlResource
,VfsResource
An InputStream can be opened for every resource if it exists in physical form, but a URL or File handle can just be returned for certain resources. The actual behavior is implementation-specific.
- Since:
- 28.12.2003
- Author:
- Juergen Hoeller, Arjen Poutsma
- See Also:
-
Method Summary
Modifier and TypeMethodDescriptionlong
Determine the content length for this resource.createRelative
(String relativePath) Create a resource relative to this resource.boolean
exists()
Determine whether this resource actually exists in physical form.default byte[]
Return the contents of this resource as a byte array.default String
getContentAsString
(Charset charset) Returns the contents of this resource as a string, using the specified charset.Return a description for this resource, to be used for error output when working with the resource.getFile()
Return a File handle for this resource.Determine the filename for this resource — typically the last part of the path — for example,"myfile.txt"
.getURI()
Return a URI handle for this resource.getURL()
Return a URL handle for this resource.default boolean
isFile()
Determine whether this resource represents a file in a file system.default boolean
isOpen()
Indicate whether this resource represents a handle with an open stream.default boolean
Indicate whether non-empty contents of this resource can be read viaInputStreamSource.getInputStream()
.long
Determine the last-modified timestamp for this resource.default ReadableByteChannel
Return aReadableByteChannel
.Methods inherited from interface org.springframework.core.io.InputStreamSource
getInputStream
-
Method Details
-
exists
boolean exists()Determine whether this resource actually exists in physical form.This method performs a definitive existence check, whereas the existence of a
Resource
handle only guarantees a valid descriptor handle. -
isReadable
default boolean isReadable()Indicate whether non-empty contents of this resource can be read viaInputStreamSource.getInputStream()
.Will be
true
for typical resource descriptors that exist since it strictly impliesexists()
semantics as of 5.1. Note that actual content reading may still fail when attempted. However, a value offalse
is a definitive indication that the resource content cannot be read.- See Also:
-
isOpen
default boolean isOpen()Indicate whether this resource represents a handle with an open stream. Iftrue
, the InputStream cannot be read multiple times, and must be read and closed to avoid resource leaks.Will be
false
for typical resource descriptors. -
isFile
default boolean isFile()Determine whether this resource represents a file in a file system.A value of
true
strongly suggests (but does not guarantee) that agetFile()
call will succeed.This is conservatively
false
by default.- Since:
- 5.0
- See Also:
-
getURL
Return a URL handle for this resource.- Throws:
IOException
- if the resource cannot be resolved as URL, i.e. if the resource is not available as a descriptor
-
getURI
Return a URI handle for this resource.- Throws:
IOException
- if the resource cannot be resolved as URI, i.e. if the resource is not available as a descriptor- Since:
- 2.5
-
getFile
Return a File handle for this resource.- Throws:
FileNotFoundException
- if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file systemIOException
- in case of general resolution/reading failures- See Also:
-
readableChannel
Return aReadableByteChannel
.It is expected that each call creates a fresh channel.
The default implementation returns
Channels.newChannel(InputStream)
with the result ofInputStreamSource.getInputStream()
.- Returns:
- the byte channel for the underlying resource (must not be
null
) - Throws:
FileNotFoundException
- if the underlying resource doesn't existIOException
- if the content channel could not be opened- Since:
- 5.0
- See Also:
-
getContentAsByteArray
Return the contents of this resource as a byte array.- 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 systemIOException
- in case of general resolution/reading failures- Since:
- 6.0.5
-
getContentAsString
Returns the contents of this resource as a string, using the specified charset.- 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 systemIOException
- in case of general resolution/reading failures- Since:
- 6.0.5
-
contentLength
Determine the content length for this resource.- Throws:
IOException
- if the resource cannot be resolved (in the file system or as some other known physical resource type)
-
lastModified
Determine the last-modified timestamp for this resource.- Throws:
IOException
- if the resource cannot be resolved (in the file system or as some other known physical resource type)
-
createRelative
Create a resource relative to this resource.- Parameters:
relativePath
- the relative path (relative to this resource)- Returns:
- the resource handle for the relative resource
- Throws:
IOException
- if the relative resource cannot be determined
-
getFilename
Determine the filename for this resource — typically the last part of the path — for example,"myfile.txt"
.Returns
null
if this type of resource does not have a filename.Implementations are encouraged to return the filename unencoded.
-
getDescription
String getDescription()Return a description for this resource, to be used for error output when working with the resource.Implementations are also encouraged to return this value from their
toString
method.- See Also:
-