com.ptc.wvs.client.pview
Class PViewCache

java.lang.Object
  com.ptc.wvs.client.pview.PViewCache

public class PViewCache

extends Object

Manages the file cache used by the viewer

Supported API: false

Extendable: false

Field Summary

private Hashtable	cache
private boolean	debug
private String	directoryCache

Constructor Summary

PViewCache()
Creates a new PViewCache.

PViewCache(String directory)
Creates a new PViewCache.

Method Summary

void	addCacheEntry(String key, String file, int usedBy) Adds a new entry to the cache
void	addCacheReference(String key, int usedBy) Returns a new unique filename in the cache
void	deleteCachedEntries(int usedBy) Deletes a reference to an entry in the cache.
private String	directorySetup(String directory) Initialize the directory
String	getCachedFilename(String key) Returns the file name from the cache
String	getNewCacheFilename(String extension) Returns a new unique filename in the cache
boolean	isDebug() Returns the debug state
boolean	isInCache(String key) Returns if the key is currently available from the cache
boolean	isInCache(String key, int usedBy) Returns if the key is currently available from the cache, and refernced by the specifed viewer
void	setDebug(boolean debug) Switches debug information on/off

Methods inherited from class java.lang.Object

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

Field Detail

cache

private Hashtable cache

directoryCache

private String directoryCache

debug

private boolean debug

Constructor Detail

PViewCache

public PViewCache()

Creates a new PViewCache. The directory used to hold the cached files will be determined by a call to PViewUtilities.getTempDirectory, a sub-directory of pvcache will be created in this directory.

PViewCache

public PViewCache(String directory)

Creates a new PViewCache. The directory specified will be used to hold the cached files in a sub-directory of pvcache. pvcache will be created if it does not already exist

Method Detail

directorySetup

private String directorySetup(String directory)

Initialize the directory

Parameters:

directory - the specified directory (it must already exist)

Returns:

the cache directory, if blank, it failed to access.

setDebug

public void setDebug(boolean debug)

Switches debug information on/off

Parameters:

debug - specifies if debug information is to be produced

isDebug

public boolean isDebug()

Returns the debug state

Returns:

debug state

getNewCacheFilename

public String getNewCacheFilename(String extension)

Returns a new unique filename in the cache

Parameters:

extension - to the filename

Returns:

unique filename

addCacheReference

public void addCacheReference(String key,
                              int usedBy)

Returns a new unique filename in the cache

Parameters:

key - typically the url to the viewable

usedBy - a reference to the viewer, typically the HWND (window handle)

addCacheEntry

public void addCacheEntry(String key,
                          String file,
                          int usedBy)

Adds a new entry to the cache

Parameters:

key - typically the url to the viewable

file - the file name in the cache directory

usedBy - a reference to the viewer, typically the HWND (window handle)

isInCache

public boolean isInCache(String key)

Returns if the key is currently available from the cache

Parameters:

key - typically the url to the viewable

Returns:

True if located in the cache

isInCache

public boolean isInCache(String key,
                         int usedBy)

Returns if the key is currently available from the cache, and refernced by the specifed viewer

Parameters:

key - typically the url to the viewable

usedBy - a reference to the viewer, typically the HWND (window handle)

Returns:

True if located in the cache

getCachedFilename

public String getCachedFilename(String key)

Returns the file name from the cache

Parameters:

key - typically the url to the viewable

Returns:

the file name

deleteCachedEntries

public void deleteCachedEntries(int usedBy)

Deletes a reference to an entry in the cache. If then no other viewer references the entry, the file is deleted from disk

Parameters:

usedBy - a reference to the viewer, typically the HWND (window handle)