wjhk.jupload2.filedata

Class PictureFileData

java.lang.Object

wjhk.jupload2.filedata.DefaultFileData

wjhk.jupload2.filedata.PictureFileData

All Implemented Interfaces:

FileData

public class PictureFileData
extends DefaultFileData

This class contains all data about files to upload as a picture. It adds the following elements to the FileData class :

• Ability to define a target format (to convert pictures to JPG before upload, for instance)
• Optional definition of a maximal width and/or height.
• Ability to rotate a picture, with addRotation(int)
• Ability to store a picture into a BufferedImage. This is actualy a bad idea within an applet (should run within a java application) : the applet runs very quickly out of memory. With pictures from my Canon EOS20D (3,5M), I can only display two pictures. The third one generates an out of memory error, despite the System.finalize and System.gc I've put everywhere in the code!

Version:

$Revision: 1586 $

Author:

etienne_sf

Field Summary

Fields inherited from class wjhk.jupload2.filedata.DefaultFileData

canRead, file, fileDir, fileModified, fileRoot, fileSize, md5sum, mimeType

Constructor Summary

Constructors

Constructor and Description
PictureFileData(File file, File root, PictureUploadPolicy uploadPolicy) Standard constructor: needs a PictureFileDataPolicy.

Method Summary

Methods

Modifier and Type	Method and Description
void	addRotation(int quarter) This function is used to rotate the picture.
void	afterUpload() Cleaning of the temporary file on the hard drive, if any.
void	beforeUpload() If this pictures needs transformation, a temporary file is created.
void	deleteTransformedPictureFile() File.deleteOnExit() is pretty unreliable, especially in applets.
void	deleteWorkingCopyPictureFile() File.deleteOnExit() is pretty unreliable, especially in applets.
static void	freeMemory(String caller, UploadPolicy uploadPolicy) Free any available memory.
Image	getImage(Canvas canvas, boolean shadow) This method creates a new Image, from the current picture.
static ImageIcon	getImageIcon(File pictureFile, int maxWidth, int maxHeight, UploadPolicy uploadPolicy) Returns an ImageIcon for the given file, resized according to the given dimensions.
InputStream	getInputStream() This function create an input stream for this file.
String	getMimeType() This function return the FileData content type.
int	getOriginalHeight()
int	getOriginalWidth()
long	getUploadLength() Returns the number of bytes, for this upload.
File	getWorkingSourceFile() Get the file that contains the original picture.
static boolean	isFileAPicture(File file) Indicates whether a file is a picture or not.
boolean	isPicture() Indicates if this file is actually a picture or not.

Methods inherited from class wjhk.jupload2.filedata.DefaultFileData

appendFileProperties, calculateMD5Sum, canRead, getDirectory, getExtension, getFile, getFileExtension, getFileLength, getFileName, getLastModified, getMD5, getRelativeDir, getRoot, isPreparedForUpload

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PictureFileData

public PictureFileData(File file,
               File root,
               PictureUploadPolicy uploadPolicy)
                throws JUploadIOException

Standard constructor: needs a PictureFileDataPolicy.

Parameters:

file - The files which data are to be handled by this instance.

root - The root directory, to calculate the relative dir (see DefaultFileData.getRelativeDir().

uploadPolicy - The current upload policy

Throws:

JUploadIOException - Encapsulation of the IOException, if any would occurs.

Method Detail

freeMemory

public static void freeMemory(String caller,
              UploadPolicy uploadPolicy)

Free any available memory. This method is called very often here, to be sure that we don't use too much memory. But we still run out of memory in some case.

Parameters:

caller - Indicate the method or treatment from which this method is called.

uploadPolicy - The current upload policy is not available, to this static method...

beforeUpload

public void beforeUpload()
                  throws JUploadException

If this pictures needs transformation, a temporary file is created. This can occurs if the original picture is bigger than the maxWidth or maxHeight, of if it has to be rotated. This temporary file contains the transformed picture.
The call to this method is optional, if the caller calls getUploadLength(). This method calls beforeUpload() if the uploadLength is unknown.

Specified by:

beforeUpload in interface FileData

Overrides:

beforeUpload in class DefaultFileData

Throws:

JUploadException - Encapsulation of the Exception, if any error would occurs.

See Also:

FileUploadThread

getUploadLength

public long getUploadLength()

Returns the number of bytes, for this upload. If needed, that is, if uploadlength is unknown, beforeUpload() is called.

Specified by:

getUploadLength in interface FileData

Overrides:

getUploadLength in class DefaultFileData

Returns:

The length of upload. In this class, this is ... the size of the original file, or the transformed file!

See Also:

PictureFileData

getInputStream

public InputStream getInputStream()
                           throws JUploadException

This function create an input stream for this file. The caller is responsible for closing this input stream.
This function assumes that the getUploadLength() method has already be called : it is responsible for creating the temporary file (if needed). If not called, the original file will be sent.

Specified by:

getInputStream in interface FileData

Overrides:

getInputStream in class DefaultFileData

Returns:

An inputStream

Throws:

JUploadException - Encapsulation of the Exception, if any would occurs.

afterUpload

public void afterUpload()

Cleaning of the temporary file on the hard drive, if any.
Note: if the debugLevel is 100 (or more) this temporary file is not removed. This allow control of this created file.

Specified by:

afterUpload in interface FileData

Overrides:

afterUpload in class DefaultFileData

getImage

public Image getImage(Canvas canvas,
             boolean shadow)
               throws JUploadException

This method creates a new Image, from the current picture. The resulting width and height will be less or equal than the given maximum width and height. The scale is maintained. Thus the width or height may be inferior than the given values.

Parameters:

canvas - The canvas on which the picture will be displayed.

shadow - True if the pictureFileData should store this picture. False if the pictureFileData instance should not store this picture. Store this picture avoid calculating the image each time the user selects it in the file panel.

Returns:

The rescaled image.

Throws:

JUploadException - Encapsulation of the Exception, if any would occurs.

addRotation

public void addRotation(int quarter)

This function is used to rotate the picture. The current rotation state is kept in the quarterRotation private attribute.

Parameters:

quarter - Number of quarters (90 degrees) the picture should rotate. 1 means rotating of 90 degrees clockwise. Can be negative.

isPicture

public boolean isPicture()

Indicates if this file is actually a picture or not.

Returns:

the isPicture flag.

getMimeType

public String getMimeType()

Description copied from class: DefaultFileData

This function return the FileData content type.

Specified by:

getMimeType in interface FileData

Overrides:

getMimeType in class DefaultFileData

Returns:

The mimeType for the file.

See Also:

FileData.getMimeType()

deleteTransformedPictureFile

public void deleteTransformedPictureFile()

File.deleteOnExit() is pretty unreliable, especially in applets. Therefore the applet provides a callback which is executed during applet termination. This method performs the actual cleanup.

deleteWorkingCopyPictureFile

public void deleteWorkingCopyPictureFile()

File.deleteOnExit() is pretty unreliable, especially in applets. Therefore the applet provides a callback which is executed during applet termination. This method performs the actual cleanup.

getWorkingSourceFile

public File getWorkingSourceFile()
                          throws JUploadIOException

Get the file that contains the original picture. This is used as a workaround for the following JVM bug: once in the navigator, it can't transform picture read from a file whose name contains non-ASCII characters, like French accents.

Returns:

The file that contains the original picture, as the source for picture transformation

Throws:

JUploadIOException

getOriginalWidth

public int getOriginalWidth()
                     throws JUploadIOException

Returns:

the originalWidth of the picture

Throws:

JUploadIOException

getOriginalHeight

public int getOriginalHeight()
                      throws JUploadIOException

Returns:

the originalHeight of the picture

Throws:

JUploadIOException

getImageIcon

public static ImageIcon getImageIcon(File pictureFile,
                     int maxWidth,
                     int maxHeight,
                     UploadPolicy uploadPolicy)
                              throws JUploadException

Returns an ImageIcon for the given file, resized according to the given dimensions. If the original file contains a pictures smaller than these width and height, the picture is returned as is (nor resized).

Parameters:

pictureFile - The file, containing a picture, from which the user wants to extract a static picture.

maxWidth - The maximum allowed width for the static picture to generate.

maxHeight - The maximum allowed height for the static picture to generate.

uploadPolicy - The current upload policy, for logging when calling freeMemory.

Returns:

The created static picture, or null if the file is null.

Throws:

JUploadException - If the ImageIcon can not be loaded.

isFileAPicture

public static boolean isFileAPicture(File file)

Indicates whether a file is a picture or not. The information is based on the fact the an ImageRead is found, or not, for this file. This test uses the core Java API. As in the windows world, file extension may be in uppercase, the test is based on the lowercase value for the given file extension.

Parameters:

file -

Returns:

true if the file can be opened as a picture, false otherwise.