jetbrains.exodus.log

Interface Loggable

All Known Subinterfaces:

RandomAccessLoggable

All Known Implementing Classes:

NullLoggable, RandomAccessLoggableImpl

public interface Loggable

For writing a loggable to log, instance should provide only type, data and its length.

If the instance is read from log, then all its methods return actual data.

Field Summary

Fields

Modifier and Type	Field and Description
static int	NO_STRUCTURE_ID
static long	NULL_ADDRESS

Method Summary

Modifier and Type	Method and Description
long	getAddress() Address of the loggable in log.
@NotNull jetbrains.exodus.ByteIterable	getData() Loggable data.
int	getDataLength() Length of the loggable data.
int	getStructureId() Returns unique id of structure that the loggable belongs to.
byte	getType() Type of loggable.
int	length() Length of the loggable with header and data.

Field Detail

NULL_ADDRESS

static final long NULL_ADDRESS

See Also:

Constant Field Values

NO_STRUCTURE_ID

static final int NO_STRUCTURE_ID

See Also:

Constant Field Values

Method Detail

getAddress

long getAddress()

Address of the loggable in log. It's available (has non-negative value) only for loggables been read from log. Loggables to write return indefinite value.

Returns:

non-negative address of the loggable.

getType

byte getType()

Type of loggable.

Returns:

integer int the range [0..127] identifying the loggable.

length

int length()

Length of the loggable with header and data.

Returns:

length of the loggable with header and data.

getData

@NotNull
@NotNull jetbrains.exodus.ByteIterable getData()

Loggable data.

Returns:

loggable data.

getDataLength

int getDataLength()

Length of the loggable data.

Returns:

length of the loggable data.

getStructureId

int getStructureId()

Returns unique id of structure that the loggable belongs to. Basically, structure id is id of a tree (BTree or Patricia). Valid structure id is non-zero.

Returns:

unique structure id.