net.sf.jomic.tools
Class ArchiveCache

java.lang.Object
  net.sf.jomic.tools.ArchiveCache

All Implemented Interfaces:

CacheInfo

public class ArchiveCache
extends java.lang.Object
implements CacheInfo

Cache for extracted archives. The cache maps the file path a a comic book archive to a directory where the extracted images are restored. While there is a size limit, it can temporarily be exeeded, for example because a single comic is bigger than the limit, or no comics can be removed because all of them are locked by a client right now.

Author:

Thomas Aglassinger

See Also:

ArchiveCacheEntry

Constructor Summary

ArchiveCache(java.io.File newBaseDir, long newMaxSize)
Create ArchiveCache storing extracted files and index in the directory newBaseDir .

Method Summary

void	attemptToReadEntries() Attempt to read entries from cacheMap.xml.
void	clear() Clear entries and remove all files in the base directory.
ArchiveCacheEntry	createCacheEntry(java.io.File newArchiveFile) Create a new cache entry for newArchiveFile using the next free index.
ArchiveCacheEntry	get(java.io.File archiveFile)
java.io.File	getBaseDir()
java.io.File	getCacheEntryDir(ArchiveCacheEntry cacheEntry) Get directory where cached files extracted from the archive are stored.
int	getEntryCount() Number of cache entries.
long	getMaxSize() Number of bytes the cache should use at the maximum.
long	getUsedSize() Number of bytes currently in use by cache.
void	put(ArchiveCacheEntry entry)
void	readEntries(java.io.Reader reader)
void	remove(java.io.File archiveFile)
void	setCacheEntrySize(ArchiveCacheEntry entry) Set the number of bytes used by entry by computing the number of bytes used by all files stored in its archive cache directory.
void	setMaxSize(long newMaxSize) Set the maximum number of bytes the cache should use.
void	writeEntries()
void	writeEntries(java.io.Writer writer)

Methods inherited from class java.lang.Object

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

Constructor Detail

ArchiveCache

public ArchiveCache(java.io.File newBaseDir,
                    long newMaxSize)
             throws java.io.FileNotFoundException

Create ArchiveCache storing extracted files and index in the directory newBaseDir . This directory must not contain any other data because clearing the cache means deleting this directory.

Parameters:

newBaseDir - the directory where extracted files will be stored

newMaxSize - intended maximum size in bytes extracted archives should use before older files are removed from the cache

Throws:

java.io.FileNotFoundException - if newBaseDir cannot be created

Method Detail

setCacheEntrySize

public void setCacheEntrySize(ArchiveCacheEntry entry)

Set the number of bytes used by entry by computing the number of bytes used by all files stored in its archive cache directory.

setMaxSize

public void setMaxSize(long newMaxSize)

Set the maximum number of bytes the cache should use. If the cache currently is bigger than that, attempt to shrink it to fit.

get

public ArchiveCacheEntry get(java.io.File archiveFile)

getBaseDir

public java.io.File getBaseDir()

getCacheEntryDir

public java.io.File getCacheEntryDir(ArchiveCacheEntry cacheEntry)

Get directory where cached files extracted from the archive are stored.

getEntryCount

public int getEntryCount()

Description copied from interface: CacheInfo

Number of cache entries.

Specified by:

getEntryCount in interface CacheInfo

getMaxSize

public long getMaxSize()

Description copied from interface: CacheInfo

Number of bytes the cache should use at the maximum.

Specified by:

getMaxSize in interface CacheInfo

getUsedSize

public long getUsedSize()

Description copied from interface: CacheInfo

Number of bytes currently in use by cache. This can be more than getMaxSize() in case there is only one entry in the cache bigger than this, or (in case entry size can not be estimated before adding them) temporarely when adding an entry before removing an old one.

Specified by:

getUsedSize in interface CacheInfo

attemptToReadEntries

public void attemptToReadEntries()

Attempt to read entries from cacheMap.xml. If the map cannot be found or is broken, start with an empty cache.

clear

public void clear()

Clear entries and remove all files in the base directory.

createCacheEntry

public ArchiveCacheEntry createCacheEntry(java.io.File newArchiveFile)

Create a new cache entry for newArchiveFile using the next free index.

put

public void put(ArchiveCacheEntry entry)

readEntries

public void readEntries(java.io.Reader reader)
                 throws java.io.IOException,
                        org.xml.sax.SAXException

Throws:

java.io.IOException

org.xml.sax.SAXException

remove

public void remove(java.io.File archiveFile)

writeEntries

public void writeEntries()
                  throws java.io.IOException

Throws:

java.io.IOException

writeEntries

public void writeEntries(java.io.Writer writer)
                  throws java.io.IOException

Throws:

java.io.IOException