FileStore

The default storage mechanism of the MVStore. This implementation persists data to a file. The file store is responsible to persist data and for free space management.

Methods
long	allocate(int length) Allocate a number of blocks and mark them as used.
long	allocate(int length) Allocate a number of blocks and mark them as used. Parameters: length - the number of bytes to allocate Returns: the start position in bytes
void	clear() Mark the file as empty.
void	clear() Mark the file as empty.
void	close() Close this store.
void	close() Close this store.
void	free(long pos, int length) Mark the space as free.
void	free(long pos, int length) Mark the space as free. Parameters: pos - the position in bytes length - the number of bytes
int	getDefaultRetentionTime() Get the default retention time for this store in milliseconds.
int	getDefaultRetentionTime() Get the default retention time for this store in milliseconds. Returns: the retention time
FileChannel	getEncryptedFile() Get the encrypted file instance, if encryption is used.
FileChannel	getEncryptedFile() Get the encrypted file instance, if encryption is used. The application may read from the file (for example for online backup), but not write to it or truncate it. Returns: the encrypted file, or null if encryption is not used
FileChannel	getFile() Get the file instance in use.
FileChannel	getFile() Get the file instance in use. The application may read from the file (for example for online backup), but not write to it or truncate it. Returns: the file
long	getFileLengthInUse()
long	getFileLengthInUse()
String	getFileName() Get the file name.
String	getFileName() Get the file name. Returns: the file name
int	getFillRate()
int	getFillRate()
long	getFirstFree()
long	getFirstFree()
long	getReadBytes() Get the number of read bytes since this store was opened.
long	getReadBytes() Get the number of read bytes since this store was opened. Returns: the number of write operations
long	getReadCount() Get the number of read operations since this store was opened.
long	getReadCount() Get the number of read operations since this store was opened. For file based stores, this is the number of file read operations. Returns: the number of read operations
long	getWriteBytes() Get the number of written bytes since this store was opened.
long	getWriteBytes() Get the number of written bytes since this store was opened. Returns: the number of write operations
long	getWriteCount() Get the number of write operations since this store was opened.
long	getWriteCount() Get the number of write operations since this store was opened. For file based stores, this is the number of file write operations. Returns: the number of write operations
boolean	isReadOnly()
boolean	isReadOnly()
void	markUsed(long pos, int length) Mark the space as in use.
void	markUsed(long pos, int length) Mark the space as in use. Parameters: pos - the position in bytes length - the number of bytes
void	open(String fileName, boolean readOnly, char[] encryptionKey) Try to open the file.
void	open(String fileName, boolean readOnly, char[] encryptionKey) Try to open the file. Parameters: fileName - the file name readOnly - whether the file should only be opened in read-only mode, even if the file is writable encryptionKey - the encryption key, or null if encryption is not used
ByteBuffer	readFully(long pos, int len) Read from the file.
ByteBuffer	readFully(long pos, int len) Read from the file. Parameters: pos - the write position len - the number of bytes to read Returns: the byte buffer
long	size() Get the file size.
long	size() Get the file size. Returns: the file size
void	sync() Flush all changes.
void	sync() Flush all changes.
String	toString()
String	toString()
void	truncate(long size) Truncate the file.
void	truncate(long size) Truncate the file. Parameters: size - the new file size
void	writeFully(long pos, ByteBuffer src) Write to the file.
void	writeFully(long pos, ByteBuffer src) Write to the file. Parameters: pos - the write position src - the source buffer

Fields
static FileChannel	encryptedFile
static FileChannel	file
static FileLock	fileLock
static String	fileName
static long	fileSize
static FreeSpaceBitSet	freeSpace
static AtomicLong	readBytes
static AtomicLong	readCount
static boolean	readOnly
static AtomicLong	writeBytes
static AtomicLong	writeCount

encryptedFile

The encrypted file (if encryption is used).

file

The file.

fileLock

The file lock.

fileName

The file name.

fileSize

The file size (cached).

freeSpace

The free spaces between the chunks. The first block to use is block 2 (the first two blocks are the store header).

readBytes

The number of read bytes.

readCount

The number of read operations.

readOnly

Whether this store is read-only.

writeBytes

The number of written bytes.

writeCount

The number of write operations.