Package org.apache.iotdb.db.metadata.mtree.store.disk.schemafile

Interface ISegment

All Known Implementing Classes:

Segment

public interface ISegment

This interface interacts with segment bytebuffer.

Field Summary

Fields

Modifier and Type	Field	Description
static int	SEG_HEADER_SIZE

Method Summary

Modifier and Type	Method	Description
void	delete()
void	extendsTo(java.nio.ByteBuffer newBuffer)	This method will write info into a buffer equal or larger to existed one.
java.util.Queue<IMNode>	getAllRecords()
long	getNextSegAddress()
long	getPrevSegAddress()
IMNode	getRecordAsIMNode(java.lang.String key)	get a MNode by its name or alias
short	getSpareSize()
boolean	hasRecordAlias(java.lang.String alias)
boolean	hasRecordKey(java.lang.String key)
int	insertRecord(java.lang.String key, java.nio.ByteBuffer buffer)	check whether enough space, notice that pairLength including 3 parts: [var length] key string itself, [int, 4 bytes] length of key string, [short, 2 bytes] key address
java.lang.String	inspect()
int	removeRecord(java.lang.String key)
void	setNextSegAddress(long nextSegAddress)
void	setPrevSegAddress(long prevSegAddress)
short	size()
void	syncBuffer()	Records are always sync with buffer, but header and key-address list are not.
java.lang.String	toString()
int	updateRecord(java.lang.String key, java.nio.ByteBuffer buffer)

Field Detail

SEG_HEADER_SIZE

static final int SEG_HEADER_SIZE

See Also:

Constant Field Values

Method Detail

insertRecord

int insertRecord(java.lang.String key,
                 java.nio.ByteBuffer buffer)
          throws RecordDuplicatedException

check whether enough space, notice that pairLength including 3 parts: [var length] key string itself, [int, 4 bytes] length of key string, [short, 2 bytes] key address

Returns:

-1 for segment overflow, otherwise for spare space

Throws:

RecordDuplicatedException

updateRecord

int updateRecord(java.lang.String key,
                 java.nio.ByteBuffer buffer)
          throws SegmentOverflowException,
                 RecordDuplicatedException

Parameters:

key - name of the record, not the alias

buffer - content of the updated record

Returns:

index of keyAddressList, -1 for not found, exception for space run out

Throws:

SegmentOverflowException - if segment runs out of memory

RecordDuplicatedException

removeRecord

int removeRecord(java.lang.String key)

getRecordAsIMNode

IMNode getRecordAsIMNode(java.lang.String key)
                  throws org.apache.iotdb.commons.exception.MetadataException

get a MNode by its name or alias

Parameters:

key - name or alias of the target node

Returns:

node instance

Throws:

org.apache.iotdb.commons.exception.MetadataException

hasRecordKey

boolean hasRecordKey(java.lang.String key)

hasRecordAlias

boolean hasRecordAlias(java.lang.String alias)

getAllRecords

java.util.Queue<IMNode> getAllRecords()
                               throws org.apache.iotdb.commons.exception.MetadataException

Throws:

org.apache.iotdb.commons.exception.MetadataException

syncBuffer

void syncBuffer()

Records are always sync with buffer, but header and key-address list are not. This method sync these values to the buffer.

size

short size()

getSpareSize

short getSpareSize()

delete

void delete()

getPrevSegAddress

long getPrevSegAddress()

getNextSegAddress

long getNextSegAddress()

setPrevSegAddress

void setPrevSegAddress(long prevSegAddress)

setNextSegAddress

void setNextSegAddress(long nextSegAddress)

extendsTo

void extendsTo(java.nio.ByteBuffer newBuffer)

This method will write info into a buffer equal or larger to existed one. There is no need to call sync before this method, since it will flush header and key-offset list directly.

Parameters:

newBuffer - target buffer

toString

java.lang.String toString()

Overrides:

toString in class java.lang.Object

inspect

java.lang.String inspect()