Interface for a resource descriptor that abstracts from the actual type of underlying resource, such as a file or class path resource.
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.
| Type | Name and description | 
|---|---|
| long | contentLength()Determine the content length for this resource. | 
| Resource | createRelative(java.lang.String relativePath)Creates a new resource relative to this one | 
| boolean | exists()Return whether this resource actually exists in physical form. | 
| java.lang.String | getDescription()Return a description for this resource, to be used for error output when working with the resource. | 
| java.io.File | getFile()Return a File handle for this resource. | 
| java.lang.String | getFilename()Determine a filename for this resource, i.e. typically the last part of the path: for example, "myfile.txt". | 
| java.io.InputStream | getInputStream()An input stream | 
| java.net.URI | getURI()Return a URI handle for this resource. | 
| java.net.URL | getURL()Return a URL handle for this resource. | 
| boolean | isReadable()Return whether the contents of this resource can be read, e.g. via getInputStream() or getFile(). | 
| long | lastModified()Determine the last-modified timestamp for this resource. | 
Determine the content length for this resource.
Creates a new resource relative to this one
relativePath -  The relative pathReturn 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.
     
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.
     
Return a File handle for this resource.
Determine a filename for this resource, i.e. typically the last part of the path: for example, "myfile.txt".
Returns null if this type of resource does not
 have a filename.
     
An input stream
Return a URI handle for this resource.
Return a URL handle for this resource.
Return whether the contents of this resource can be read, e.g. via getInputStream() or getFile().
Will be true for typical resource descriptors;
 note that actual content reading may still fail when attempted.
 However, a value of false is a definitive indication
 that the resource content cannot be read.
     
Determine the last-modified timestamp for this resource.