Package net.metanotion.io.block.index

Class BSkipSpan<K extends Comparable<? super K>,V>

java.lang.Object

net.metanotion.util.skiplist.SkipSpan<K,V>

net.metanotion.io.block.index.BSkipSpan<K,V>

All Implemented Interfaces:

Flushable

Direct Known Subclasses:

IBSkipSpan

public class BSkipSpan<K extends Comparable<? super K>,V>
extends SkipSpan<K,V>

On-disk format:

   First Page:
     Magic number (int)
     overflow page (unsigned int)
     previous page (unsigned int)
     next page (unsigned int)
     max keys (unsigned short)
     number of keys (unsigned short)
     for each key:
         key length (unsigned short)
         value length (unsigned short)
         key data
         value data

   Overflow pages:
     Magic number (int)
     next overflow page (unsigned int)

Field Summary

Fields

Modifier and Type	Field	Description
protected final BlockFile	bf
static final int	CONT_HEADER_LEN
protected static final int	HEADER_LEN
protected boolean	isKilled
protected Serializer<K>	keySer
protected static final int	MAGIC
protected int	nextPage
protected int	overflowPage
protected int	page
protected int	prevPage
protected int	spanSize
protected Serializer<V>	valSer

Fields inherited from class net.metanotion.util.skiplist.SkipSpan

keys, MAX_SIZE, next, nKeys, prev, vals

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BSkipSpan(BlockFile bf, BSkipList<K,V> bsl)
	BSkipSpan(BlockFile bf, BSkipList<K,V> bsl, int spanPage, Serializer<K> key, Serializer<V> val)

Method Summary

Modifier and Type	Method	Description
void	flush()
static void	init(BlockFile bf, int page, int spanSize)
void	killInstance()
protected void	loadData()	I2P - second half of load() Load the whole span's keys and values into memory
protected void	loadData(boolean flushOnError)	I2P - second half of load() Load the whole span's keys and values into memory
protected static <X extends Comparable<? super X>, Y> void	loadInit(BSkipSpan<X,Y> bss, BlockFile bf, BSkipList<X,Y> bsl, int spanPage, Serializer<X> key, Serializer<Y> val)	I2P - first half of load() Only read the span headers
protected void	lostEntries(int firstBadEntry, int lastGoodPage)	Attempt to recover from corrupt data in this span.
SkipSpan<K,V>	newInstance(SkipList<K,V> sl)
String	toString()

Methods inherited from class net.metanotion.util.skiplist.SkipSpan

firstKey, get, getEnd, getSpan, print, put, remove

Methods inherited from class java.lang.Object

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

Field Details

MAGIC

protected static final int MAGIC

See Also:

• Constant Field Values

HEADER_LEN

protected static final int HEADER_LEN

See Also:

• Constant Field Values

CONT_HEADER_LEN

public static final int CONT_HEADER_LEN

See Also:

• Constant Field Values

bf

protected final BlockFile bf

page

protected int page

overflowPage

protected int overflowPage

prevPage

protected int prevPage

nextPage

protected int nextPage

keySer

protected Serializer<K extends Comparable<? super K>> keySer

valSer

protected Serializer<V> valSer

spanSize

protected int spanSize

isKilled

protected boolean isKilled

Constructor Details

BSkipSpan

protected BSkipSpan(BlockFile bf,
 BSkipList<K,V> bsl)

BSkipSpan

public BSkipSpan(BlockFile bf,
 BSkipList<K,V> bsl,
 int spanPage,
 Serializer<K> key,
 Serializer<V> val)
          throws IOException

Throws:

IOException

Method Details

init

public static void init(BlockFile bf,
 int page,
 int spanSize)
                 throws IOException

Throws:

IOException

newInstance

public SkipSpan<K,V> newInstance(SkipList<K,V> sl)

Overrides:

newInstance in class SkipSpan<K extends Comparable<? super K>,V>

killInstance

public void killInstance()

Overrides:

killInstance in class SkipSpan<K extends Comparable<? super K>,V>

flush

public void flush()

Specified by:

flush in interface Flushable

Overrides:

flush in class SkipSpan<K extends Comparable<? super K>,V>

loadInit

protected static <X extends Comparable<? super X>,
Y>
void loadInit(BSkipSpan<X,Y> bss,
 BlockFile bf,
 BSkipList<X,Y> bsl,
 int spanPage,
 Serializer<X> key,
 Serializer<Y> val)
       throws IOException

I2P - first half of load() Only read the span headers

Throws:

IOException

loadData

protected void loadData()
                 throws IOException

I2P - second half of load() Load the whole span's keys and values into memory

Throws:

IOException

loadData

protected void loadData(boolean flushOnError)
                 throws IOException

I2P - second half of load() Load the whole span's keys and values into memory

Parameters:

flushOnError - set to false if you are going to flush anyway

Throws:

IOException

lostEntries

protected void lostEntries(int firstBadEntry,
 int lastGoodPage)

Attempt to recover from corrupt data in this span. All entries starting with firstBadEntry are lost. Zero out the overflow page on lastGoodPage, and corect the number of entries in the first page. We don't attempt to free the lost continuation pages.

toString

public String toString()

Overrides:

toString in class Object