Package org.rostore.v2.keys

Class KeyBlockEntry

java.lang.Object

org.rostore.v2.fixsize.ValidatingEntry

org.rostore.v2.fixsize.FixSizeEntry

org.rostore.v2.keys.KeyBlockEntry

public class KeyBlockEntry
extends FixSizeEntry

Represents an entry with exactly one key.

Every entry contains: block index, block offset, id, eol, version.

Block index and offset reference a region in the var size block where the key data is stored.

Var size block can be either multi block or single block.

Multi block would reference a key, which size is greater than one block. A single (or multi-entry) block would reference a block that contain one complete or several keys.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	KeyBlockEntry(FixSizeEntryBlock<KeyBlockEntry> keyBlock, VarSizeBlock varSizeBlock, RecordLengths recordLengths)

Method Summary

Modifier and Type	Method	Description
int	getEntrySize()	Provides an entry size in bytes
long	getId()	Reads an id associated with the current entry
long	getKeyBlockIndex()	Reads the key block index from the current entry
long	getKeyBlockOffset()	Provides an offset of the key in the key block
Record	getRecord()	Reads the record from the current position
RecordLengths	getRecordLengths()	A class with length in bytes of key-entry elements
void	incKeyBlockOffset(long add)	Increments the offset associated with the key by provided increment
boolean	isExpired()	Checks if current entry is expired (according to EOL)
boolean	isExpired(long currentTimeSecs)	Checks if current entry is expired (according to EOL)
void	moveTo(int index)	Sets the current index to the value as provided.
void	setKeyBlockIndex(long blockIndex)	Sets the key block to the provided index
void	setKeyBlockOffset(long offset)	Sets offset of the key in the key block
void	setRecord(Record record)	Put record to the current position / entry
boolean	sync(boolean value)	Manages if the var size block should be initialized when the entry is selected
String	toString()	Provides an explicit string representation of the entry location

Methods inherited from class org.rostore.v2.fixsize.FixSizeEntry

expand, getEntriesNumber, getEntryLocation, getFixSizeEntryBlock, getHash, insert, moveToHash, remove

Methods inherited from class org.rostore.v2.fixsize.ValidatingEntry

first, getIndex, invalid, invalidate, isFirst, last, next, previous, throwExceptionIfInvalid, valid, validate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

KeyBlockEntry

protected KeyBlockEntry(FixSizeEntryBlock<KeyBlockEntry> keyBlock,
 VarSizeBlock varSizeBlock,
 RecordLengths recordLengths)

Method Details

getRecordLengths

public RecordLengths getRecordLengths()

A class with length in bytes of key-entry elements

Returns:

lengths of record's elements

toString

public String toString()

Description copied from class: FixSizeEntry

Provides an explicit string representation of the entry location

Overrides:

toString in class FixSizeEntry

sync

public boolean sync(boolean value)

Manages if the var size block should be initialized when the entry is selected

Parameters:

value - true if the block should be initialized when the entry is changed

Returns:

previous value of sync mode

moveTo

public void moveTo(int index)

Sets the current index to the value as provided.

The function would mark the entry as invalid if the index does not lay withing the boundaries: 0..ValidatingEntry.getEntriesNumber()

Overrides:

moveTo in class ValidatingEntry

Parameters:

index - the index to be set

getKeyBlockIndex

public long getKeyBlockIndex()

Reads the key block index from the current entry

Returns:

key block index

getId

public long getId()

Reads an id associated with the current entry

Returns:

the id as it stored in the entry

setRecord

public void setRecord(Record record)

Put record to the current position / entry

Parameters:

record - the record to write to the key entry

getRecord

public Record getRecord()

Reads the record from the current position

Returns:

the record object

isExpired

public boolean isExpired()

Checks if current entry is expired (according to EOL)

Returns:

true if the entry already expired

isExpired

public boolean isExpired(long currentTimeSecs)

Checks if current entry is expired (according to EOL)

Parameters:

currentTimeSecs - current timestamp in seconds

Returns:

true if the entry expired according to the given timestamp

setKeyBlockIndex

public void setKeyBlockIndex(long blockIndex)

Sets the key block to the provided index

Parameters:

blockIndex - the block index

getKeyBlockOffset

public long getKeyBlockOffset()

Provides an offset of the key in the key block

Returns:

the offset within the key block

setKeyBlockOffset

public void setKeyBlockOffset(long offset)

Sets offset of the key in the key block

Parameters:

offset - the offset to associate with the key

incKeyBlockOffset

public void incKeyBlockOffset(long add)

Increments the offset associated with the key by provided increment

Parameters:

add - how much to increment

getEntrySize

public int getEntrySize()

Provides an entry size in bytes

Specified by:

getEntrySize in class FixSizeEntry

Returns:

the entry size in bytes