net.sourceforge.java.feednread.backend.configuration
Class ImageManager

java.lang.Object
  net.sourceforge.java.feednread.backend.configuration.ImageManager

public class ImageManager

extends Object

Central application Image management class. Disposes of a memory cache for application Images which caches an Image in memory the first time it is requested. In addition an icon cache for Favorite icon Images is used which caches icons from a Favorite's host in a local persistent cache.

Don't forget to call the dispose() method on application exit to clear off the memory cache.

Author:

Sebastian Machhausen

Field Summary

private static int	DEFAULT_ICON_HEIGHT The default icon Image height
private static int	DEFAULT_ICON_WIDTH The default icon Image width
private static ImageRegistry	DEFAULT_REGISTRY The default ImageRegistry to cache all requested Images.

Constructor Summary

ImageManager()

Method Summary

private static void	cacheIcon(String hostUrl) Puts the icon deposited at the specified hostUrl in the local icon cache.
private static ImageDescriptor	createImageDescriptor(String key) Gets the ImageDescriptor matching the specified key.
static void	dispose() Disposes all Image resources created by this ImageManager.
static Image	getIcon(String favoriteUrl) Gets the icon Image denoted by the specified favoriteUrl from the cache using both cache levels, i.e.
static Image	getIcon(String favoriteUrl, boolean useSecondLevelCache) Gets the icon Image denoted by the specified favoriteUrl from the cache.
static Image	getImage(String key) Gets the Image denoted by the specified key from the internal ImageRegistry.
private static Image	getImage(String key, boolean returnMissingOnError, boolean scaleImage) Gets the Image denoted by the specified key from the internal ImageRegistry.
static ImageDescriptor	getImageDescriptor(String key) Gets the ImageDescriptor denoted by the specified key from the internal ImageRegistry.
static Image	getNewsFeedTypeImage(String type) Gets the newsfeed type Image based on the specified syndication type.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_REGISTRY

private static final ImageRegistry DEFAULT_REGISTRY

The default ImageRegistry to cache all requested Images.

DEFAULT_ICON_WIDTH

private static final int DEFAULT_ICON_WIDTH

The default icon Image width

See Also:

Constant Field Values

DEFAULT_ICON_HEIGHT

private static final int DEFAULT_ICON_HEIGHT

The default icon Image height

See Also:

Constant Field Values

Constructor Detail

ImageManager

public ImageManager()

Method Detail

dispose

public static void dispose()

Disposes all Image resources created by this ImageManager.

getImage

public static Image getImage(String key)

Gets the Image denoted by the specified key from the internal ImageRegistry. An Image is initialized and cached the first time it is requested.

Parameters:

key - the key to query the Image for

Returns:

the Image denoted by the specified key

getImage

private static Image getImage(String key,
                              boolean returnMissingOnError,
                              boolean scaleImage)

Gets the Image denoted by the specified key from the internal ImageRegistry. An Image is initialized and cached the first time it is requested.

Parameters:

key - the key to query the Image for

returnMissingOnError - if true returns a default image; otherwise returns null

scaleImage - true to scale the Image to the default size; false to get it in original size

Returns:

the Image denoted by the specified key

getImageDescriptor

public static ImageDescriptor getImageDescriptor(String key)

Gets the ImageDescriptor denoted by the specified key from the internal ImageRegistry. An ImageDescriptor is initialized and cached the first time it is requested.

Parameters:

key - the key to query the ImageDescriptor for

Returns:

the ImageDescriptor denoted by the specified key

getNewsFeedTypeImage

public static Image getNewsFeedTypeImage(String type)

Gets the newsfeed type Image based on the specified syndication type.

Parameters:

type - String the syndication type

getIcon

public static Image getIcon(String favoriteUrl)

Gets the icon Image denoted by the specified favoriteUrl from the cache using both cache levels, i.e. first level and second cache.

Parameters:

favoriteUrl - the url of the Favorite to get the icon Image for

Returns:

the icon Image

getIcon

public static Image getIcon(String favoriteUrl,
                            boolean useSecondLevelCache)

Gets the icon Image denoted by the specified favoriteUrl from the cache.

Parameters:

favoriteUrl - the url of the Favorite to get the icon Image for

useSecondLevelCache - true to also use second level cache (web) if the icon Image is not found in the first level cache (local).

Returns:

the icon Image

cacheIcon

private static void cacheIcon(String hostUrl)

Puts the icon deposited at the specified hostUrl in the local icon cache.

Parameters:

hostUrl - the url of the host to get the icon Image from

createImageDescriptor

private static ImageDescriptor createImageDescriptor(String key)

Gets the ImageDescriptor matching the specified key.

Parameters:

key - the key that identifies the image to get the descriptor for

Returns:

the ImageDescriptor matching the specified key