com.orientechnologies.orient.core.storage.impl.local.paginated.wal

Interface OWALChanges

All Known Implementing Classes:

OWALChangesTree, OWALPageChangesPortion

public interface OWALChanges

keep partial changes of a page for a transaction.

use get* to access to the original content decorated with the changes. use set* to add a change.

Created by tglman on 24/12/15.

Method Summary

Modifier and Type	Method and Description
void	applyChanges(ByteBuffer buffer) Apply the changes to a page.
int	fromStream(int offset, byte[] stream) Read changes from a stream.
byte[]	getBinaryValue(ByteBuffer buffer, int offset, int len)
byte	getByteValue(ByteBuffer buffer, int offset)
int	getIntValue(ByteBuffer buffer, int offset)
long	getLongValue(ByteBuffer buffer, int offset)
short	getShortValue(ByteBuffer buffer, int offset)
boolean	hasChanges()
OWALChanges	inverse(ByteBuffer buffer)
void	moveData(ByteBuffer buffer, int from, int to, int len)
int	serializedSize() Return the size needed in a buffer in case of serialization.
void	setBinaryValue(ByteBuffer buffer, byte[] value, int offset)
void	setByteValue(ByteBuffer buffer, byte value, int offset)
void	setIntValue(ByteBuffer buffer, int value, int offset)
void	setLongValue(ByteBuffer buffer, long value, int offset)
int	toStream(int offset, byte[] stream) Serialize the changes to a stream.

Method Detail

getByteValue

byte getByteValue(ByteBuffer buffer,
                  int offset)

getBinaryValue

byte[] getBinaryValue(ByteBuffer buffer,
                      int offset,
                      int len)

getShortValue

short getShortValue(ByteBuffer buffer,
                    int offset)

getIntValue

int getIntValue(ByteBuffer buffer,
                int offset)

getLongValue

long getLongValue(ByteBuffer buffer,
                  int offset)

setLongValue

void setLongValue(ByteBuffer buffer,
                  long value,
                  int offset)

setIntValue

void setIntValue(ByteBuffer buffer,
                 int value,
                 int offset)

setByteValue

void setByteValue(ByteBuffer buffer,
                  byte value,
                  int offset)

setBinaryValue

void setBinaryValue(ByteBuffer buffer,
                    byte[] value,
                    int offset)

moveData

void moveData(ByteBuffer buffer,
              int from,
              int to,
              int len)

hasChanges

boolean hasChanges()

applyChanges

void applyChanges(ByteBuffer buffer)

Apply the changes to a page.

Parameters:

buffer - Presents page where apply the changes.

serializedSize

int serializedSize()

Return the size needed in a buffer in case of serialization.

Returns:

the required size.

toStream

int toStream(int offset,
             byte[] stream)

Serialize the changes to a stream. needed for write the changes to the WAL

Parameters:

offset - starting writing offset for the provided buffer.

stream - buffer where write the content, should be of minimal size of offset+ @{link @serializedSize()}

Returns:

the number of written bytes + the offset, can be used as offset of the next operation.

fromStream

int fromStream(int offset,
               byte[] stream)

Read changes from a stream. Needed from restore from WAL.

Parameters:

offset - the offest in the buffer where start to read.

stream - the buffer to read.

Returns:

the offset+read bytes.

inverse

OWALChanges inverse(ByteBuffer buffer)