DiskFileItem (Apache Commons FileUpload 1.6.0 API)

java.lang.Object
- org.apache.commons.fileupload.disk.DiskFileItem

All Implemented Interfaces:

FileItem, FileItemHeadersSupport

Direct Known Subclasses:

DefaultFileItem
```
public class DiskFileItem
extends Object
implements FileItem
```
The default implementation of the FileItem interface.
After retrieving an instance of this class from a DiskFileItemFactory instance (see #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.

Since:

FileUpload 1.1

Field Summary

Fields
Modifier and Type Field and Description

static String DEFAULT_CHARSET
Default content charset to be used when no explicit charset parameter is provided by the sender.

Fields
Modifier and Type	Field and Description
`static String`	`DEFAULT_CHARSET` Default content charset to be used when no explicit charset parameter is provided by the sender.

Constructor Summary

Constructors
Constructor and Description
`DiskFileItem(String fieldName, String contentType, boolean isFormField, String fileName, int sizeThreshold, File repository)` Constructs a new `DiskFileItem` instance.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`delete()` Deletes the underlying storage for a file item, including deleting any associated temporary disk file.
`protected void`	`finalize()` Removes the file contents from the temporary storage.
`byte[]`	`get()` Gets the contents of the file as an array of bytes.
`String`	`getCharSet()` Gets the content charset passed by the agent or `null` if not defined.
`String`	`getContentType()` Gets the content type passed by the agent or `null` if not defined.
`String`	`getDefaultCharset()` Gets the default charset for use when no explicit charset parameter is provided by the sender.
`String`	`getFieldName()` Gets the name of the field in the multipart form corresponding to this file item.
`FileItemHeaders`	`getHeaders()` Gets the file item headers.
`InputStream`	`getInputStream()` Gets an `InputStream` that can be used to retrieve the contents of the file.
`String`	`getName()` Gets the original file name in the client's file system.
`OutputStream`	`getOutputStream()` Gets an `OutputStream` that can be used for storing the contents of the file.
`long`	`getSize()` Gets the size of the file.
`File`	`getStoreLocation()` Gets the `File` object for the `FileItem`'s data's temporary location on the disk.
`String`	`getString()` Gets the contents of the file as a String, using the default character encoding.
`String`	`getString(String charset)` Gets the contents of the file as a String, using the specified encoding.
`protected File`	`getTempFile()` Creates and returns a `File` representing a uniquely named temporary file in the configured repository path.
`boolean`	`isFormField()` Tests 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`	`setDefaultCharset(String charset)` Sets the default charset for use when no explicit charset parameter is provided by the sender.
`void`	`setFieldName(String fieldName)` Sets the field name used to reference this file item.
`void`	`setFormField(boolean formField)` Sets whether or not a `FileItem` instance represents a simple form field.
`void`	`setHeaders(FileItemHeaders headers)` Sets the file item headers.
`String`	`toString()` Returns a string representation of this object.
`void`	`write(File file)` A convenience method to write an uploaded item to disk.

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - DEFAULT_CHARSET
```
public static final String 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.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - DiskFileItem
```
public DiskFileItem(String fieldName,
                    String contentType,
                    boolean isFormField,
                    String fileName,
                    int sizeThreshold,
                    File repository)
```
    Constructs a new DiskFileItem instance.
    
    Parameters:
    
    fieldName - The name of the form field.
    
    contentType - The content type passed by the browser or null if not specified.
    
    isFormField - Whether or not this item is a plain form field, as opposed to a file upload.
    
    fileName - The original file name in the user's file system, or null if not specified.
    
    sizeThreshold - The threshold, in bytes, below which items will be retained in memory and above which they will be stored as a file.
    
    repository - The data repository, which is the directory in which files will be created, should the item size exceed the threshold.
- Method Detail
  - delete
```
public void delete()
```
    Deletes the underlying storage for a file item, including deleting any associated temporary disk file. Although this storage will be deleted automatically when the FileItem instance is garbage collected, this method can be used to ensure that this is done at an earlier time, thus preserving system resources.
    
    Specified by:
    
    delete in interface FileItem
  - finalize
```
protected void finalize()
                 throws Throwable
```
    Removes the file contents from the temporary storage.
    
    Overrides:
    
    finalize in class Object
    
    Throws:
    
    Throwable - Thrown by Object.finalize().
  - get
```
public byte[] 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:
    
    get in interface FileItem
    
    Returns:
    
    The contents of the file as an array of bytes or null if the data cannot be read.
    
    Throws:
    
    UncheckedIOException - if an I/O error occurs.
    
    OutOfMemoryError - if an array of the required size cannot be allocated, for example the file is larger that 2GB.
  - getCharSet
```
public String getCharSet()
```
    Gets the content charset passed by the agent or null if not defined.
    
    Returns:
    
    The content charset passed by the agent or null if not defined.
  - getContentType
```
public String getContentType()
```
    Gets the content type passed by the agent or null if not defined.
    
    Specified by:
    
    getContentType in interface FileItem
    
    Returns:
    
    The content type passed by the agent or null if not defined.
  - getDefaultCharset
```
public String getDefaultCharset()
```
    Gets the default charset for use when no explicit charset parameter is provided by the sender.
    
    Returns:
    
    the default charset
  - getFieldName
```
public String getFieldName()
```
    Gets the name of the field in the multipart form corresponding to this file item.
    
    Specified by:
    
    getFieldName in interface FileItem
    
    Returns:
    
    The name of the form field.
    
    See Also:
    
    setFieldName(String)
  - getHeaders
```
public FileItemHeaders getHeaders()
```
    Gets the file item headers.
    
    Specified by:
    
    getHeaders in interface FileItemHeadersSupport
    
    Returns:
    
    The file items headers.
  - getInputStream
```
public InputStream getInputStream()
                           throws IOException
```
    Gets an InputStream that can be used to retrieve the contents of the file.
    
    Specified by:
    
    getInputStream in interface FileItem
    
    Returns:
    
    An InputStream that can be used to retrieve the contents of the file.
    
    Throws:
    
    IOException - if an error occurs.
  - getName
```
public String getName()
```
    Gets the original file name in the client's file system.
    
    Specified by:
    
    getName in interface FileItem
    
    Returns:
    
    The original file name in the client's file system.
    
    Throws:
    
    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().
  - getOutputStream
```
public OutputStream getOutputStream()
                             throws IOException
```
    Gets an OutputStream that can be used for storing the contents of the file.
    
    Specified by:
    
    getOutputStream in interface FileItem
    
    Returns:
    
    An OutputStream that can be used for storing the contents of the file.
    
    Throws:
    
    IOException - if an error occurs (never happens).
  - getSize
```
public long getSize()
```
    Gets the size of the file.
    
    Specified by:
    
    getSize in interface FileItem
    
    Returns:
    
    The size of the file, in bytes.
  - getStoreLocation
```
public File getStoreLocation()
```
    Gets the File object for the FileItem's data's temporary location on the disk. Note that for FileItems that have their data stored in memory, this method will return null. When handling large files, you can use File.renameTo(java.io.File) 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 null if the data is stored in memory.
  - getString
```
public String getString()
```
    Gets the contents of the file as a String, using the default character encoding. This method uses get() to retrieve the contents of the file.
    TODO Consider making this method throw UnsupportedEncodingException.
    
    Specified by:
    
    getString in interface FileItem
    
    Returns:
    
    The contents of the file, as a string.
  - getString
```
public String getString(String charset)
                 throws UnsupportedEncodingException
```
    Gets the contents of the file as a String, using the specified encoding. This method uses get() to retrieve the contents of the file.
    
    Specified by:
    
    getString in interface FileItem
    
    Parameters:
    
    charset - The charset to use.
    
    Returns:
    
    The contents of the file, as a string.
    
    Throws:
    
    UnsupportedEncodingException - if the requested character encoding is not available.
  - getTempFile
```
protected File getTempFile()
```
    Creates and returns a File representing a uniquely named temporary file in the configured repository path. The lifetime of the file is tied to the lifetime of the FileItem instance; 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 File to be used for temporary storage.
  - isFormField
```
public boolean isFormField()
```
    Tests whether or not a FileItem instance represents a simple form field.
    
    Specified by:
    
    isFormField in interface FileItem
    
    Returns:
    
    true if the instance represents a simple form field; false if it represents an uploaded file.
    
    See Also:
    
    setFormField(boolean)
  - isInMemory
```
public boolean isInMemory()
```
    Provides a hint as to whether or not the file contents will be read from memory.
    
    Specified by:
    
    isInMemory in interface FileItem
    
    Returns:
    
    true if the file contents will be read from memory; false otherwise.
  - setDefaultCharset
```
public void setDefaultCharset(String charset)
```
    Sets the default charset for use when no explicit charset parameter is provided by the sender.
    
    Parameters:
    
    charset - the default charset
  - setFieldName
```
public void setFieldName(String fieldName)
```
    Sets the field name used to reference this file item.
    
    Specified by:
    
    setFieldName in interface FileItem
    
    Parameters:
    
    fieldName - The name of the form field.
    
    See Also:
    
    getFieldName()
  - setFormField
```
public void setFormField(boolean formField)
```
    Sets whether or not a FileItem instance represents a simple form field.
    
    Specified by:
    
    setFormField in interface FileItem
    
    Parameters:
    
    formField - true if the instance represents a simple form field; false if it represents an uploaded file.
    
    See Also:
    
    isFormField()
  - setHeaders
```
public void setHeaders(FileItemHeaders headers)
```
    Sets the file item headers.
    
    Specified by:
    
    setHeaders in interface FileItemHeadersSupport
    
    Parameters:
    
    headers - The file items headers.
  - toString
```
public String toString()
```
    Returns a string representation of this object.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    a string representation of this object.
  - write
```
public void write(File file)
           throws Exception
```
    A convenience method to write 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:
    
    write in interface FileItem
    
    Parameters:
    
    file - The File into which the uploaded item should be stored.
    
    Throws:
    
    Exception - if an error occurs.

Class DiskFileItem

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_CHARSET

Constructor Detail

DiskFileItem

Method Detail

delete

finalize

get

getCharSet

getContentType

getDefaultCharset

getFieldName

getHeaders

getInputStream

getName

getOutputStream

getSize

getStoreLocation

getString

getString

getTempFile

isFormField

isInMemory

setDefaultCharset

setFieldName

setFormField

setHeaders

toString

write