org.alfresco.repo.content.caching

Class ContentCacheImpl

java.lang.Object

org.alfresco.repo.content.caching.ContentCacheImpl

All Implemented Interfaces:

ContentCache

public class ContentCacheImpl
extends Object
implements ContentCache

The one and only implementation of the ContentCache class. Binary content data itself is stored on disk in the location specified by cacheRoot.

The in-memory lookup table is provided by a SimpleCache implementation.

Author:

Matt Ward

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ContentCacheImpl.CacheWriter This FileContentWriter subclass allows for the temp cache file to be renamed to a cache file proper, e.g filename.tmp becomes filename.bin
protected static class	ContentCacheImpl.NumericFileNameComparator

Constructor Summary

Constructors

Constructor and Description
ContentCacheImpl()

Method Summary

Modifier and Type	Method and Description
boolean	contains(Key key) Allows caller to perform lookup using a Key.
boolean	contains(String contentUrl) Check to see if the content - specified by URL - exists in the cache.
static String	createNewCacheFilePath() Creates a relative path for a new cache file.
void	deleteFile(String url) Deletes the cached content file for the specified URL.
String	getCacheFilePath(String contentUrl) Get the path of a cache file for the given content URL - will return null if there is no entry in the cache for the specified URL.
File	getCacheRoot() Returns the directory where cache files will be written (cacheRoot).
String	getContentUrl(File file) Get a content URL from the cache - keyed by File.
org.alfresco.service.cmr.repository.ContentReader	getReader(String contentUrl) Retrieve a ContentReader for the cached content specified by URL.
org.alfresco.service.cmr.repository.ContentWriter	getWriter(String url) Retrieve a ContentWriter to write content to a cache file.
void	processFiles(FileHandler handler) Ask the ContentCacheImpl to visit all the content files in the cache.
boolean	put(String contentUrl, org.alfresco.service.cmr.repository.ContentReader source) Put an item into cache - this will populate both a disk file (with content) and the in-memory lookup table (with the URL and cache file location).
void	putIntoLookup(Key key, String value) Put an item in the lookup table.
void	remove(String contentUrl) Remove a cached item from the in-memory lookup table.
void	removeAll() Remove all items from the lookup table.
void	setCacheRoot(File cacheRoot) Specify the directory where cache files will be written.
void	setMemoryStore(org.alfresco.repo.cache.SimpleCache<Key,String> memoryStore) Configure ContentCache with a memory store.

Methods inherited from class java.lang.Object

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

Constructor Detail

ContentCacheImpl

public ContentCacheImpl()

Method Detail

contains

public boolean contains(String contentUrl)

Description copied from interface: ContentCache

Check to see if the content - specified by URL - exists in the cache.

Note that just because the in-memory cache has a record of the content item having been placed into the cache, it does not mean that the disk item is guaranteed to be there. The temp file clean-up process, for example, may have removed it.

Specified by:

contains in interface ContentCache

Parameters:

contentUrl - String

Returns:

true if the URL exists in the in-memory cache. It may therefore be cached on disk.

contains

public boolean contains(Key key)

Allows caller to perform lookup using a Key.

Parameters:

key - Key

Returns:

true if the cache contains, false otherwise.

putIntoLookup

public void putIntoLookup(Key key,
                          String value)

Put an item in the lookup table.

Parameters:

key - Key

value - String

getCacheFilePath

public String getCacheFilePath(String contentUrl)

Get the path of a cache file for the given content URL - will return null if there is no entry in the cache for the specified URL.

Parameters:

contentUrl - String

Returns:

cache file path

getContentUrl

public String getContentUrl(File file)

Get a content URL from the cache - keyed by File.

Parameters:

file - File

Returns:

String

getReader

public org.alfresco.service.cmr.repository.ContentReader getReader(String contentUrl)

Description copied from interface: ContentCache

Retrieve a ContentReader for the cached content specified by URL.

Specified by:

getReader in interface ContentCache

Parameters:

contentUrl - String

Returns:

ContentReader

put

public boolean put(String contentUrl,
                   org.alfresco.service.cmr.repository.ContentReader source)

Description copied from interface: ContentCache

Put an item into cache - this will populate both a disk file (with content) and the in-memory lookup table (with the URL and cache file location). Empty content will NOT be cached - in which case false is returned.

Specified by:

put in interface ContentCache

Parameters:

contentUrl - String

source - ContentReader

Returns:

true if the content was cached, false otherwise.

remove

public void remove(String contentUrl)

Description copied from interface: ContentCache

Remove a cached item from the in-memory lookup table. Implementation should not remove the actual cached content (file) - this should be left to the clean-up process or can be deleted with ContentCache.deleteFile(String).

Specified by:

remove in interface ContentCache

Parameters:

contentUrl - String

removeAll

public void removeAll()

Remove all items from the lookup table. Cached content files are not removed.

deleteFile

public void deleteFile(String url)

Description copied from interface: ContentCache

Deletes the cached content file for the specified URL. To remove the item from the lookup table also, use ContentCache.remove(String) after calling this method.

Specified by:

deleteFile in interface ContentCache

Parameters:

url - String

getWriter

public org.alfresco.service.cmr.repository.ContentWriter getWriter(String url)

Description copied from interface: ContentCache

Retrieve a ContentWriter to write content to a cache file. Upon closing the stream a listener will add the new content file to the in-memory lookup table.

Specified by:

getWriter in interface ContentCache

Parameters:

url - url

Returns:

ContentWriter

createNewCacheFilePath

public static String createNewCacheFilePath()

Creates a relative path for a new cache file. The path is based upon the current date/time: year/month/day/hour/minute/guid.bin

e.g. 2011/12/3/13/55/27d56416-bf9f-4d89-8f9e-e0a52de0a59e.bin

Returns:

The relative path for the new cache file.

setMemoryStore

public void setMemoryStore(org.alfresco.repo.cache.SimpleCache<Key,String> memoryStore)

Configure ContentCache with a memory store.

Parameters:

memoryStore - the memoryStore to set

setCacheRoot

public void setCacheRoot(File cacheRoot)

Specify the directory where cache files will be written.

Parameters:

cacheRoot - File

getCacheRoot

public File getCacheRoot()

Returns the directory where cache files will be written (cacheRoot).

Specified by:

getCacheRoot in interface ContentCache

Returns:

cacheRoot

processFiles

public void processFiles(FileHandler handler)

Ask the ContentCacheImpl to visit all the content files in the cache.

Parameters:

handler - FileHandler