Class DiskFileItem
- All Implemented Interfaces:
FileItem<DiskFileItem>,FileItemHeadersProvider<DiskFileItem>
FileItem interface.
After retrieving an instance of this class from a DiskFileItemFactory instance (see
org.apache.commons.fileupload2.core.servlet.ServletFileUpload
#parseRequest(javax.servlet.http.HttpServletRequest)), you may either request all contents of 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.
Temporary files, which are created for file items, should be deleted later on. The best way to do this is using a
FileCleaningTracker, which you can set on the DiskFileItemFactory. However, if you do use such a tracker, then you must
consider the following: Temporary files are automatically deleted as soon as they are no longer needed. (More precisely, when the corresponding instance of
File is garbage collected.) This is done by the so-called reaper thread, which is started and stopped automatically by the
FileCleaningTracker when there are files to be tracked. It might make sense to terminate that thread, for example, if your web
application ends. See the section on "Resource cleanup" in the users guide of Commons FileUpload.
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Nested Class Summary
Nested Classes -
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final CharsetDefault content charset to be used when no explicit charset parameter is provided by the sender. -
Method Summary
Modifier and TypeMethodDescriptionstatic DiskFileItem.Builderbuilder()Constructs a newDiskFileItem.Builder.static StringcheckFileName(String fileName) Tests if the file name is valid.delete()Deletes the underlying storage for a file item, including deleting any associated temporary disk file.byte[]get()Gets the contents of the file as an array of bytes.Gets the content charset passed by the agent ornullif not defined.Gets the default charset for use when no explicit charset parameter is provided by the sender.Gets the content type passed by the agent ornullif not defined.Gets the name of the field in the multipart form corresponding to this file item.Gets the file item headers.Gets anInputStreamthat can be used to retrieve the contents of the file.getName()Gets the original file name in the client's file system.Gets anOutputStreamthat can be used for storing the contents of the file.getPath()Gets thePathfor theFileItem's data's temporary location on the disk.longgetSize()Gets the size of the file.Gets the contents of the file as a String, using the default character encoding.Gets the contents of the file as a String, using the specified encoding.protected PathCreates and returns aFilerepresenting a uniquely named temporary file in the configured repository path.booleanTests whether or not aFileIteminstance represents a simple form field.booleanProvides a hint as to whether or not the file contents will be read from memory.setCharsetDefault(Charset charset) Sets the default charset for use when no explicit charset parameter is provided by the sender.setFieldName(String fieldName) Sets the field name used to reference this file item.setFormField(boolean state) Specifies whether or not aFileIteminstance represents a simple form field.setHeaders(FileItemHeaders headers) Sets the file item headers.toString()Returns a string representation of this object.Writes an uploaded item to disk.
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Field Details
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DEFAULT_CHARSET
Default content charset to be used when no explicit charset parameter is provided by the sender. Media subtypes of the "text" type are defined to have a default charset value of "ISO-8859-1" when received via HTTP.
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Method Details
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builder
Constructs a newDiskFileItem.Builder.- Returns:
- a new
DiskFileItem.Builder.
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checkFileName
Tests if the file name is valid. For example, if it contains a NUL characters, it's invalid. If the file name is valid, it will be returned without any modifications. Otherwise, throw anInvalidPathException.- Parameters:
fileName- The file name to check- Returns:
- Unmodified file name, if valid.
- Throws:
InvalidPathException- The file name is invalid.
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delete
Deletes the underlying storage for a file item, including deleting any associated temporary disk file. This method can be used to ensure that this is done at an earlier time, thus preserving system resources.- Specified by:
deletein interfaceFileItem<DiskFileItem>- Returns:
- this
- Throws:
IOException- if an error occurs.
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get
Gets the contents of the file as an array of bytes. If the contents of the file were not yet cached in memory, they will be loaded from the disk storage and cached.- Specified by:
getin interfaceFileItem<DiskFileItem>- Returns:
- The contents of the file as an array of bytes or
nullif the data cannot be read. - Throws:
UncheckedIOException- if an I/O error occurs.OutOfMemoryError- SeeFiles.readAllBytes(Path): If an array of the required size cannot be allocated, for example the file is larger that2GB
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getCharset
Gets the content charset passed by the agent ornullif not defined.- Returns:
- The content charset passed by the agent or
nullif not defined.
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getCharsetDefault
Gets the default charset for use when no explicit charset parameter is provided by the sender.- Returns:
- the default charset
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getContentType
Gets the content type passed by the agent ornullif not defined.- Specified by:
getContentTypein interfaceFileItem<DiskFileItem>- Returns:
- The content type passed by the agent or
nullif not defined.
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getFieldName
Gets the name of the field in the multipart form corresponding to this file item.- Specified by:
getFieldNamein interfaceFileItem<DiskFileItem>- Returns:
- The name of the form field.
- See Also:
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getHeaders
Gets the file item headers.- Specified by:
getHeadersin interfaceFileItemHeadersProvider<DiskFileItem>- Returns:
- The file items headers.
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getInputStream
Gets anInputStreamthat can be used to retrieve the contents of the file.- Specified by:
getInputStreamin interfaceFileItem<DiskFileItem>- Returns:
- An
InputStreamthat can be used to retrieve the contents of the file. - Throws:
IOException- if an error occurs.
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getName
Gets the original file name in the client's file system.- Specified by:
getNamein interfaceFileItem<DiskFileItem>- Returns:
- The original file name in the client's file system.
- Throws:
InvalidPathException- 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 useInvalidPathException.getInput().
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getOutputStream
Gets anOutputStreamthat can be used for storing the contents of the file.- Specified by:
getOutputStreamin interfaceFileItem<DiskFileItem>- Returns:
- An
OutputStreamthat can be used for storing the contents of the file.
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getPath
Gets thePathfor theFileItem's data's temporary location on the disk. Note that forFileItems that have their data stored in memory, this method will returnnull. When handling large files, you can useFiles.move(Path,Path,CopyOption...)to move the file to new location without copying the data, if the source and destination locations reside within the same logical volume.- Returns:
- The data file, or
nullif the data is stored in memory.
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getSize
Gets the size of the file.- Specified by:
getSizein interfaceFileItem<DiskFileItem>- Returns:
- The size of the file, in bytes.
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getString
Gets the contents of the file as a String, using the default character encoding. This method usesget()to retrieve the contents of the file.TODO Consider making this method throw UnsupportedEncodingException.
- Specified by:
getStringin interfaceFileItem<DiskFileItem>- Returns:
- The contents of the file, as a string.
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getString
Gets the contents of the file as a String, using the specified encoding. This method usesget()to retrieve the contents of the file.- Specified by:
getStringin interfaceFileItem<DiskFileItem>- Parameters:
charset- The charset to use.- Returns:
- The contents of the file, as a string.
- Throws:
IOException- if an I/O error occurs
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getTempFile
Creates and returns aFilerepresenting a uniquely named temporary file in the configured repository path. The lifetime of the file is tied to the lifetime of theFileIteminstance; the file will be deleted when the instance is garbage collected.Note: Subclasses that override this method must ensure that they return the same File each time.
- Returns:
- The
Fileto be used for temporary storage.
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isFormField
Tests whether or not aFileIteminstance represents a simple form field.- Specified by:
isFormFieldin interfaceFileItem<DiskFileItem>- Returns:
trueif the instance represents a simple form field;falseif it represents an uploaded file.- See Also:
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isInMemory
Provides a hint as to whether or not the file contents will be read from memory.- Specified by:
isInMemoryin interfaceFileItem<DiskFileItem>- Returns:
trueif the file contents will be read from memory;falseotherwise.
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setCharsetDefault
Sets the default charset for use when no explicit charset parameter is provided by the sender.- Parameters:
charset- the default charset- Returns:
- this
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setFieldName
Sets the field name used to reference this file item.- Specified by:
setFieldNamein interfaceFileItem<DiskFileItem>- Parameters:
fieldName- The name of the form field.- Returns:
- this
- See Also:
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setFormField
Specifies whether or not aFileIteminstance represents a simple form field.- Specified by:
setFormFieldin interfaceFileItem<DiskFileItem>- Parameters:
state-trueif the instance represents a simple form field;falseif it represents an uploaded file.- Returns:
- this
- See Also:
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setHeaders
Sets the file item headers.- Specified by:
setHeadersin interfaceFileItemHeadersProvider<DiskFileItem>- Parameters:
headers- The file items headers.- Returns:
- this
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toString
Returns a string representation of this object. -
write
Writes an uploaded item to disk.The client code is not concerned with whether or not the item is stored in memory, or on disk in a temporary location. They just want to write the uploaded item to a file.
This implementation first attempts to rename the uploaded item to the specified destination file, if the item was originally written to disk. Otherwise, the data will be copied to the specified file.
This method is only guaranteed to work once, the first time it is invoked for a particular item. This is because, in the event that the method renames a temporary file, that file will no longer be available to copy or rename again at a later time.
- Specified by:
writein interfaceFileItem<DiskFileItem>- Parameters:
file- TheFileinto which the uploaded item should be stored.- Returns:
- this
- Throws:
IOException- if an error occurs.
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