com::cosylab::logging::client::cache::LogMultiFileCache Class Reference

Inheritance diagram for com::cosylab::logging::client::cache::LogMultiFileCache:

Collaboration diagram for com::cosylab::logging::client::cache::LogMultiFileCache:

Public Member Functions
	LogMultiFileCache (long fileSize) throws LogCacheException
	LogMultiFileCache () throws LogCacheException
ILogEntry	getLog (Integer logKey) throws LogCacheException
synchronized int	add (ILogEntry log) throws LogCacheException
synchronized void	deleteLog (Integer logKey) throws LogCacheException
int	getSize ()
Integer	getLastLog ()
Integer	getFirstLog ()
void	deleteLogs (Collection< Integer > keys) throws LogCacheException
synchronized void	clear () throws LogCacheException
void	replaceLog (Integer key, ILogEntry log) throws LogCacheException
Iterator< ILogEntry >	iterator ()
Set< Integer >	keySet ()
int	getFirstLogs (int n, Collection< Integer > keys)
long	getLogFileSize () throws LogCacheException
synchronized long	getFilesSize () throws IOException
long	getMaxFileSize () throws LogCacheException
void	setDebugTrace (boolean flag) throws LogCacheException
void	printFileTableInfo () throws LogCacheException
int	getNumberOfCacheFiles ()
Static Public Attributes
static final String	FILEMAXSIZE_PROPERTY_NAME = "jlog.cache.fileMaxSize"
static final long	DEFAULT_FILEMAXSIZE = 10000000
Private Member Functions
void	printDebugTrace (String traceInfo)
MultiFileTableRecord	createNewFileRecord () throws LogCacheException
MultiFileTableRecord	searchFileLogTable (Integer logKey) throws LogCacheException
Static Private Member Functions
static long	getDefaultMaxFileSize ()
Private Attributes
boolean	debugTrace = false
long	fileMaxSize
Vector< MultiFileTableRecord >	logFileTable = new Vector<MultiFileTableRecord>()
volatile int	logsInCache = 0
int	ID = -1

Detailed Description

This class manages a set of LogBufferedFileCache objects allowing the storing of logs in different files, though from the user point of view the logs are stored or retrieved from single data store.

This is due to the fact that files can grow up to a given size and hence setting a limit on the number of logs that can be collected.

Logs are added to a file until it reaches a given size, then a new file is created. Logs have different length and therefore the number of logs in each File Buffered Cache will be different (see example below).

Logs are accessible by the user through a keyword (logKey) which is implemented as an increased running number. On the other hand, within each File Buffered Cache they have their own numbering system which starts from 0 to the maximum number of logs.

Example :

logKey logCounter Buffered File Range Cache Range -------------------------------------------------------- 0 - 10 11 0 - 10 file1 11 - 25 15 0 - 14 file2 26 - 32 7 0 - 6 file3 33 - 50 18 0 - 18 file4

When logs are deleted they are no longer accessible : when all logs stored in a single file are marked as deleted the corresponding logCounter = 0 and as consequence the file itself is removed.

Using the example let's assume we delete the logs with the following keyword : 26,27,28,31,32, from now on these logs will not be accessible for the user.

logKey logCounter Buffered File Range Cache Range -------------------------------------------------------- 0 - 10 11 0 - 10 file1 11 - 25 15 0 - 14 file2 26 - 32 2 0 - 6 file3 33 - 50 18 0 - 18 file4

If we delete also logs with keywords 29 and 30 the logCounter will be zero and file3 will be deleted.

logKey Mapping When retrieving the log we need to re-map the global log keyword into the keyword used to add the log to the specific Buffered File Cache. This is done by simply subtracting the minimum key value from the logKey.

Example : Retrieve logKey 20. logKey 20 is stored in the second Buffered File Cache and it is accessible with the local key = (20 - 11) = 9

Author:: mcomin

Constructor & Destructor Documentation

com::cosylab::logging::client::cache::LogMultiFileCache::LogMultiFileCache ( long fileSize ) throws LogCacheException [inline]

Builds a LogMultiFileCache objects setting the maximum size of the cache files

Parameters:

fileSize

The maximum size of cache files

References fileMaxSize, and printDebugTrace().

com::cosylab::logging::client::cache::LogMultiFileCache::LogMultiFileCache ( ) throws LogCacheException [inline]

Constructor

The maximum size of the files is read from the system properties. If the property is not found a default value is used.

References getDefaultMaxFileSize().

Member Function Documentation

synchronized int com::cosylab::logging::client::cache::LogMultiFileCache::add ( ILogEntry log ) throws LogCacheException [inline]

Add a log to the cache

Parameters:

log

The log to add to the cache

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

References com::cosylab::logging::client::cache::MultiFileTableRecord::addLog(), createNewFileRecord(), fileMaxSize, com::cosylab::logging::client::cache::MultiFileTableRecord::flushBuffer(), com::cosylab::logging::client::cache::MultiFileTableRecord::getFileSize(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMaxLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMinLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getNumOfLogs(), ID, logFileTable, logsInCache, and printDebugTrace().

synchronized void com::cosylab::logging::client::cache::LogMultiFileCache::clear ( ) throws LogCacheException [inline]

Clear the Map i.e. remove all the logs and keys from the map

Exceptions:

LogCacheException

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

References logFileTable, and logsInCache.

Referenced by alma::acs::jlog::test::MultiFileCacheTest::tearDown(), and alma::acs::jlog::test::MultiFileCacheTest::testClear().

MultiFileTableRecord com::cosylab::logging::client::cache::LogMultiFileCache::createNewFileRecord ( ) throws LogCacheException [inline, private]

Creates a new record for the log file table : min/max log indexes are initialized according to the total number of received logs.

The create LogFileTableRecord is added to the table of file records.

References logFileTable.

Referenced by add().

synchronized void com::cosylab::logging::client::cache::LogMultiFileCache::deleteLog ( Integer logKey ) throws LogCacheException [inline]

Delete a log with the given key.

Parameters:

pos

The key of the log to delete

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

References com::cosylab::logging::client::cache::MultiFileTableRecord::clear(), com::cosylab::logging::client::cache::MultiFileTableRecord::deleteLog(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMaxLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMinLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getNumOfLogs(), logFileTable, logsInCache, printDebugTrace(), and searchFileLogTable().

Referenced by deleteLogs(), alma::acs::jlog::test::MultiFileCacheTest::testFileCreation(), alma::acs::jlog::test::MultiFileCacheTest::testFileDeletion(), alma::acs::jlog::test::MultiFileCacheTest::testGetFirstLog(), alma::acs::jlog::test::MultiFileCacheTest::testGetLastLog(), alma::acs::jlog::test::MultiFileCacheTest::testGetSize(), and alma::acs::jlog::test::MultiFileCacheTest::testkKeySet().

void com::cosylab::logging::client::cache::LogMultiFileCache::deleteLogs ( Collection< Integer > keys ) throws LogCacheException [inline]

Delete a set of logs

Parameters:

keys

The keys of logs to delete

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

References deleteLog().

static long com::cosylab::logging::client::cache::LogMultiFileCache::getDefaultMaxFileSize ( ) [inline, static, private]

Get the max size of the file out of the system properties or uses the default value if the property does not exist

References DEFAULT_FILEMAXSIZE, and FILEMAXSIZE_PROPERTY_NAME.

Referenced by LogMultiFileCache().

synchronized long com::cosylab::logging::client::cache::LogMultiFileCache::getFilesSize ( ) throws IOException [inline]

Return the disk space used by all the files of the cache.

Returns:: The disk space used by all the files of the cache

Exceptions:

IOException

In case of error getting the size of one of the files

References logFileTable.

Referenced by alma::acs::logging::table::LogEntryTableModelBase::usedDiskSpace().

Integer com::cosylab::logging::client::cache::LogMultiFileCache::getFirstLog ( ) [inline]

Return the key of the first valid log (FIFO). The key of the first log is 0 but it can change if the log 0 has been deleted.

Returns:: The key of the first log null if the cache is empty

See also:: com.cosylab.logging.client.cache.ILogMap

Exceptions:

In

case of error getting the first log

Implements com::cosylab::logging::client::cache::ILogMap.

References com::cosylab::logging::client::cache::MultiFileTableRecord::getFirstLog(), logFileTable, and logsInCache.

int com::cosylab::logging::client::cache::LogMultiFileCache::getFirstLogs	(	int	n,
		Collection< Integer >	keys
	)			`[inline]`

Append at most n keys from the first valid logs to the collection. First here means first in the FIFO policy.

The number of added keys can be less then n if the cache doesn't contain enough logs.

Parameters:

	n	The desired number of keys of first logs
	keys	The collection to add they keys to

Returns:: The number of keys effectively added

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

References logFileTable.

Referenced by com::cosylab::logging::CacheTest::testGetLogs().

Integer com::cosylab::logging::client::cache::LogMultiFileCache::getLastLog ( ) [inline]

Return the key of the last valid log (FIFO) The key of the last log is the key of the last inserted log but it can change if such log has been deleted

Returns:: The key of the last inserted log null if the cache is empty

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

References com::cosylab::logging::client::cache::MultiFileTableRecord::getLastLog(), logFileTable, and logsInCache.

ILogEntry com::cosylab::logging::client::cache::LogMultiFileCache::getLog ( Integer logKey ) throws LogCacheException [inline]

Retrieves a log by means of its keyword.

Parameters:

pos

The key of the log to retrieve

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

References com::cosylab::logging::client::cache::MultiFileTableRecord::getLog(), and searchFileLogTable().

Referenced by alma::acs::jlog::test::MultiFileCacheTest::testGet(), alma::acs::jlog::test::MultiFileCacheTest::testkKeySet(), and alma::acs::jlog::test::MultiFileCacheTest::testReplace().

long com::cosylab::logging::client::cache::LogMultiFileCache::getLogFileSize ( ) throws LogCacheException [inline]

Return the size of the last log file used by the cache (it is here for testing purposes)

See also:

References com::cosylab::logging::client::cache::MultiFileTableRecord::getFileSize(), and logFileTable.

Referenced by alma::acs::jlog::test::MultiFileCacheTest::testFileCreation().

long com::cosylab::logging::client::cache::LogMultiFileCache::getMaxFileSize ( ) throws LogCacheException [inline]

Return the current maximum size of the log file

See also:

References fileMaxSize.

Referenced by alma::acs::jlog::test::MultiFileCacheTest::setUp().

int com::cosylab::logging::client::cache::LogMultiFileCache::getNumberOfCacheFiles ( ) [inline]

Returns:: the number of the files used by the cache

References logFileTable.

Referenced by alma::acs::logging::table::LogEntryTableModelBase::numberOfUsedFiles(), alma::acs::jlog::test::MultiFileCacheTest::testClear(), and alma::acs::jlog::test::MultiFileCacheTest::testFileDeletion().

int com::cosylab::logging::client::cache::LogMultiFileCache::getSize ( ) [inline]

Returns:: The number of logs in the map

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

References logsInCache.

Iterator<ILogEntry> com::cosylab::logging::client::cache::LogMultiFileCache::iterator ( ) [inline]

Return an Iterator to browse the logs in the map. The order the iterator returns the logs is that of the keys.

Returns:: an Iterator over the elements in this map

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

Set<Integer> com::cosylab::logging::client::cache::LogMultiFileCache::keySet ( ) [inline]

The keys in the map

Returns:: The key in the map

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

Reimplemented in com::cosylab::logging::client::cache::LogCache.

References logFileTable.

Referenced by alma::acs::jlog::test::MultiFileCacheTest::testkKeySet().

void com::cosylab::logging::client::cache::LogMultiFileCache::printDebugTrace ( String traceInfo ) [inline, private]

Prints trace info if traceDebug flag is true

References debugTrace.

Referenced by add(), deleteLog(), and LogMultiFileCache().

void com::cosylab::logging::client::cache::LogMultiFileCache::printFileTableInfo ( ) throws LogCacheException [inline]

Return the current maximum size of the log file

See also:

References com::cosylab::logging::client::cache::MultiFileTableRecord::getFileSize(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMaxLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getMinLogIdx(), com::cosylab::logging::client::cache::MultiFileTableRecord::getNumOfLogs(), logFileTable, and logsInCache.

Referenced by alma::acs::jlog::test::MultiFileCacheTest::testFileCreation(), alma::acs::jlog::test::MultiFileCacheTest::testFileDeletion(), and alma::acs::jlog::test::MultiFileCacheTest::testGetLastLog().

void com::cosylab::logging::client::cache::LogMultiFileCache::replaceLog	(	Integer	key,
		ILogEntry	log
	)			throws LogCacheException `[inline]`

Replace the log in the given position with the new one

Parameters:

	position	The position of the log to replace
	log	The key (identifier) of the log

See also:: com.cosylab.logging.client.cache.ILogMap

Implements com::cosylab::logging::client::cache::ILogMap.

References com::cosylab::logging::client::cache::MultiFileTableRecord::replaceLog(), and searchFileLogTable().

Referenced by alma::acs::logging::table::LogEntryTableModelBase::replaceLog(), alma::acs::jlog::test::MultiFileCacheTest::testReplace(), and com::cosylab::logging::CacheTest::testReplace().

MultiFileTableRecord com::cosylab::logging::client::cache::LogMultiFileCache::searchFileLogTable ( Integer logKey ) throws LogCacheException [inline, private]

Looks in the log file table in which file buffered cache the log has been stored.

The search is made by checking the min and max key of the logs contained in each record against the key of the searched log. As a consequence the record returned by this method is the only one record that can contain this log but it could be that the log is not there (for example it has been deleted)

Parameters:

logKey

The key of the log to look for