public interface FileItem extends java.io.Serializable, FileItemHeadersSupport
This class represents a file or form item that was received within a
multipart/form-data
POST request.
After retrieving an instance of this class from a FileUpload
instance (see
#parseRequest(javax.servlet.http.HttpServletRequest)
), you may
either request all contents of the file at once using get()
or
request an InputStream
with
getInputStream()
and process the file without attempting to load
it into memory, which may come handy with large files.
While this interface does not extend
javax.activation.DataSource
per se (to avoid a seldom used
dependency), several of the defined methods are specifically defined with
the same signatures as methods in that interface. This allows an
implementation of this interface to also implement
javax.activation.DataSource
with minimal additional work.
Modifier and Type | Method and Description |
---|---|
void |
delete()
Deletes the underlying storage for a file item, including deleting any
associated temporary disk file.
|
byte[] |
get()
Returns the contents of the file item as an array of bytes.
|
java.lang.String |
getContentType()
Returns the content type passed by the browser or
null if
not defined. |
java.lang.String |
getFieldName()
Returns the name of the field in the multipart form corresponding to
this file item.
|
java.io.InputStream |
getInputStream()
Returns an
InputStream that can be
used to retrieve the contents of the file. |
java.lang.String |
getName()
Returns the original filename in the client's filesystem, as provided by
the browser (or other client software).
|
java.io.OutputStream |
getOutputStream()
Returns an
OutputStream that can
be used for storing the contents of the file. |
long |
getSize()
Returns the size of the file item.
|
java.lang.String |
getString()
Returns the contents of the file item as a String, using the default
character encoding.
|
java.lang.String |
getString(java.lang.String encoding)
Returns the contents of the file item as a String, using the specified
encoding.
|
boolean |
isFormField()
Determines whether or not a
FileItem instance represents
a simple form field. |
boolean |
isInMemory()
Provides a hint as to whether or not the file contents will be read
from memory.
|
void |
setFieldName(java.lang.String name)
Sets the field name used to reference this file item.
|
void |
setFormField(boolean state)
Specifies whether or not a
FileItem instance represents
a simple form field. |
void |
write(java.io.File file)
A convenience method to write an uploaded item to disk.
|
getHeaders, setHeaders
java.io.InputStream getInputStream() throws java.io.IOException
InputStream
that can be
used to retrieve the contents of the file.InputStream
that can be
used to retrieve the contents of the file.java.io.IOException
- if an error occurs.java.lang.String getContentType()
null
if
not defined.null
if
not defined.java.lang.String getName()
InvalidFileNameException
- The file name contains a NUL character,
which might be an indicator of a security attack. If you intend to
use the file name anyways, catch the exception and use
InvalidFileNameException#getName().boolean isInMemory()
true
if the file contents will be read from memory;
false
otherwise.long getSize()
byte[] get()
java.lang.String getString(java.lang.String encoding) throws java.io.UnsupportedEncodingException
get()
to retrieve the
contents of the item.encoding
- The character encoding to use.java.io.UnsupportedEncodingException
- if the requested character
encoding is not available.java.lang.String getString()
get()
to retrieve the
contents of the item.void write(java.io.File file) throws java.lang.Exception
This method is not guaranteed to succeed if called more than once for the same item. This allows a particular implementation to use, for example, file renaming, where possible, rather than copying all of the underlying data, thus gaining a significant performance benefit.
file
- The File
into which the uploaded item should
be stored.java.lang.Exception
- if an error occurs.void delete()
FileItem
instance is garbage
collected, this method can be used to ensure that this is done at an
earlier time, thus preserving system resources.java.lang.String getFieldName()
void setFieldName(java.lang.String name)
name
- The name of the form field.boolean isFormField()
FileItem
instance represents
a simple form field.true
if the instance represents a simple form
field; false
if it represents an uploaded file.void setFormField(boolean state)
FileItem
instance represents
a simple form field.state
- true
if the instance represents a simple form
field; false
if it represents an uploaded file.java.io.OutputStream getOutputStream() throws java.io.IOException
OutputStream
that can
be used for storing the contents of the file.OutputStream
that can be used
for storing the contensts of the file.java.io.IOException
- if an error occurs.Copyright © 2010 - 2020 Adobe. All Rights Reserved