com.alee.extended.list.ThumbnailGenerator Maven / Gradle / Ivy
/*
* This file is part of WebLookAndFeel library.
*
* WebLookAndFeel library is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* WebLookAndFeel library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with WebLookAndFeel library. If not, see generators = new WeakHashMap ();
/**
* Generator references map operations lock.
*/
protected static final Object generatorsLock = new Object ();
/**
* File list this generator is working for.
*/
@NotNull
protected final WebFileList list;
/**
* Element thumbnail is being generated for.
*/
@NotNull
protected final FileElement element;
/**
* Requested thumbnail size.
*/
@NotNull
protected final Dimension size;
/**
* Whether should generate disabled state thumbnail or not.
*/
protected final boolean disabled;
/**
* Whether generation was aborted or not.
*/
protected boolean aborted;
/**
* Constructs thumbnail generator for the specified file element.
*
* @param list file list this generator is working for
* @param element element to queue thumbnail generation for
* @param size requested thumbnail size
* @param disabled whether should generate disabled state thumbnail or not
*/
public ThumbnailGenerator ( @NotNull final WebFileList list, @NotNull final FileElement element, @NotNull final Dimension size,
final boolean disabled )
{
this.list = list;
this.element = element;
this.size = size;
this.disabled = disabled;
this.aborted = false;
}
/**
* Returns file list this generator is working for.
*
* @return file list this generator is working for
*/
@NotNull
public WebFileList getList ()
{
return list;
}
/**
* Returns file element for which thumbnail is being generated.
*
* @return file element for which thumbnail is being generated
*/
@NotNull
public FileElement getElement ()
{
return element;
}
/**
* Returns whether disabled thumbnail will also be generated or not.
*
* @return true if disabled thumbnail will also be generated, false otherwise
*/
public boolean isDisabled ()
{
return disabled;
}
/**
* Returns whether this generator was aborted or not.
*
* @return true if this generator was aborted, false otherwise
*/
public boolean isAborted ()
{
return aborted;
}
/**
* Abort thumbnail generation.
* Note that actual abort might occur after long-running operations, but it will surely cancel thumbnail update.
*/
public void abort ()
{
this.aborted = true;
}
/**
* Starts thumbnail generation.
*/
@Override
public void run ()
{
// Process abort check here
if ( !aborted )
{
// Creating thumbnail
createThumbnail ( element.getFile (), list.isGenerateThumbnails () );
// Process abort check here
if ( !aborted )
{
// Updating list view
// Repaint doesn't really require EDT but this is simply a dirty trick to invoke this call later
CoreSwingUtils.invokeLater ( new Runnable ()
{
@Override
public void run ()
{
list.repaint ( element );
}
} );
// Perform final cleanups
cleanup ();
}
else
{
// Perform abort cleanups
cleanup ();
}
}
else
{
// Perform abort cleanups
cleanup ();
}
}
/**
* Cleanup cached reference to this generator.
* This is required mostly in cases when generator was not aborted.
*/
protected void cleanup ()
{
synchronized ( generatorsLock )
{
// Perform cleanup only if current generator is still an active one for this element
final ThumbnailGenerator generator = generators.get ( element );
if ( generator == this )
{
// Updating thumbnail load state
synchronized ( element.getLock () )
{
element.setThumbnailQueued ( false );
element.setDisabledThumbnailQueued ( false );
}
// Removing element generator reference
generators.remove ( element );
}
}
}
/**
* Generates thumbnail for the specified file.
*
* @param file file to generate thumbnail for
* @param preview whether should create thumbnail
*/
protected void createThumbnail ( @NotNull final File file, final boolean preview )
{
final FileThumbnailProvider thumbnailProvider = list.getThumbnailProvider ();
if ( thumbnailProvider != null && thumbnailProvider.accept ( file ) )
{
// Using thumbnail provider to generate thumbnail icon
final Icon thumb = element.getEnabledThumbnail () != null ? element.getEnabledThumbnail () :
thumbnailProvider.provide ( file, size, preview );
if ( thumb != null )
{
// Applying custom thumbnail
applyThumbnail ( thumb );
}
else
{
// Creating standard thumbnail
createStandardThumbnail ( file, preview );
}
}
else
{
// Creating standard thumbnail
createStandardThumbnail ( file, preview );
}
}
/**
* Generates standard thumbnail for the specified {@link File}.
*
* @param file {@link File} to generate standard thumbnail for
* @param preview whether should create thumbnail for image from the specified {@link File}
*/
protected void createStandardThumbnail ( @NotNull final File file, final boolean preview )
{
// Using either image thumbnails or default file extension icons
if ( preview && ImageUtils.isImageSupported ( file.getName () ) )
{
// If thumbnail was already specified we should re-use it
// It will save us a lot of time if we simply need to generate disabled state in addition to enabled one
final Icon thumb = element.getEnabledThumbnail () != null ? element.getEnabledThumbnail () :
createThumbnailIcon ( file );
if ( thumb != null )
{
// Applying standard image thumbnail
applyThumbnail ( thumb );
}
else
{
// Applying standard extension icon
applyStandardIcon ( file );
}
}
else
{
// Applying standard extension icon
applyStandardIcon ( file );
}
}
/**
* Returns thumbnail for image from the specified {@link File}.
* Note that this method will generate {@link Icon} with a static image, so any GIF or other animated images will be static.
*
* @param file file to generate thumbnail for
* @return thumbnail for image from the specified {@link File}
*/
@Nullable
protected Icon createThumbnailIcon ( @NotNull final File file )
{
Icon thumbnail;
try
{
final BufferedImage bufferedImage = ImageUtils.loadBufferedImage ( new FileResource ( file ) );
final BufferedImage previewImage = ImageUtils.createImageThumbnail ( bufferedImage, Math.min ( size.width, size.height ) );
final ImageIcon previewIcon = new ImageIcon ( previewImage );
previewIcon.setDescription ( previewImage.getWidth () + "x" + previewImage.getHeight () );
thumbnail = previewIcon;
}
catch ( final Exception e )
{
thumbnail = null;
}
return thumbnail;
}
/**
* Applies generated thumbnail to the element.
*
* @param thumbnail thumbnail icon
*/
protected void applyThumbnail ( @NotNull final Icon thumbnail )
{
if ( !aborted )
{
// Applying custom generated thumbnail icon
synchronized ( element.getLock () )
{
if ( element.isThumbnailQueued () )
{
// We had to check that queue wasn't cancelled from outside
element.setEnabledThumbnail ( thumbnail );
}
}
if ( !aborted && disabled )
{
// Re-using enabled state thumbnail to generate disabled state one
final Icon disabledThumbnail = ImageUtils.createDisabledCopy ( thumbnail );
if ( !aborted && element.isDisabledThumbnailQueued () )
{
// We had to check that queue wasn't cancelled from outside
element.setDisabledThumbnail ( disabledThumbnail );
}
}
}
}
/**
* Applies standard icon to the element.
*
* @param file file to apply standard icon to
*/
protected void applyStandardIcon ( @NotNull final File file )
{
if ( !aborted )
{
// Generating standard file extension icon
final Icon enabledThumbnail = FileUtils.getStandardFileIcon ( file, true, true );
if ( !aborted )
{
if ( element.isThumbnailQueued () )
{
// We had to check that queue wasn't cancelled from outside
element.setEnabledThumbnail ( enabledThumbnail );
}
if ( !aborted && disabled )
{
// Standard icons are cached so we don't need to re-use enabled icon for disabled state one generation
final Icon disabledThumbnail = FileUtils.getStandardFileIcon ( file, true, false );
if ( !aborted && element.isDisabledThumbnailQueued () )
{
// We had to check that queue wasn't cancelled from outside
element.setDisabledThumbnail ( disabledThumbnail );
}
}
}
}
}
/**
* Adds specified element into thumbnails generation queue.
*
* @param list file list this generator is working for
* @param element element to queue thumbnail generation for
* @param size requested thumbnail size
* @param disabled whether should generate disabled state thumbnail or not
*/
public static void queueThumbnailLoad ( @NotNull final WebFileList list, @NotNull final FileElement element,
@NotNull final Dimension size, final boolean disabled )
{
synchronized ( generatorsLock )
{
synchronized ( element.getLock () )
{
// Skip generation if it was already done or in queue
if ( disabled ? !element.isDisabledThumbnailQueued () && element.getDisabledThumbnail () == null :
!element.isThumbnailQueued () && element.getEnabledThumbnail () == null )
{
// Updating thumbnail load state
element.setThumbnailQueued ( true );
element.setDisabledThumbnailQueued ( disabled );
// Queueing thumbnail generation
final ThumbnailGenerator generator = new ThumbnailGenerator ( list, element, size, disabled );
generators.put ( element, generator );
TaskManager.execute ( TaskManager.COMPUTATION, generator );
}
}
}
}
/**
* Forces thumbnail generation to be aborted for the specified element.
*
* @param element element to abort thumbnail generation for
*/
public static void abortThumbnailLoad ( @NotNull final FileElement element )
{
synchronized ( generatorsLock )
{
// Aborting generator
final ThumbnailGenerator generator = generators.get ( element );
if ( generator != null )
{
generator.abort ();
}
// Cleaning up previous thumbnails
synchronized ( element.getLock () )
{
element.setEnabledThumbnail ( null );
element.setThumbnailQueued ( false );
element.setDisabledThumbnail ( null );
element.setDisabledThumbnailQueued ( false );
}
}
}
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