Package org.eclipse.jgit.internal.storage.reftable

Class BlockReader

java.lang.Object

org.eclipse.jgit.internal.storage.reftable.BlockReader

class BlockReader
extends java.lang.Object

Reads a single block for ReftableReader. Instances are tied to a specific block in the file so are not reused for other blocks. Instances hold an offset into the block.

Field Summary

Fields

Modifier and Type	Field	Description
private byte	blockType
private byte[]	buf
private int	bufLen
private long	endPosition
private int	keysEnd
private int	keysStart
private byte[]	nameBuf
private int	nameLen
private int	ptr
private int	restartCnt
private int	restartTbl
private boolean	truncated
private int	valueType

Constructor Summary

Constructors

Constructor	Description
BlockReader()

Method Summary

Modifier and Type	Method	Description
(package private) static int	decodeBlockLen(int typeAndSize)
(package private) long	endPosition()
private long	inflateBuf(BlockSource src, long pos, int blockLen, int fileBlockSize)
private static java.io.IOException	invalidBlock()
private static java.io.IOException	invalidBlock(java.lang.Throwable cause)
(package private) boolean	match(byte[] match, boolean matchIsPrefix)
(package private) java.lang.String	name()
private static Ref	newRef(java.lang.String name, long updateIndex)
(package private) boolean	next()
private void	parseBlockStart(BlockSource src, long pos, int fileBlockSize)
(package private) void	parseKey()
(package private) void	readBlock(BlockSource src, long pos, int fileBlockSize)
private void	readBlockIntoBuf(BlockSource src, long pos, int size)
(package private) LongList	readBlockPositionList()
private short	readInt16()
(package private) ReflogEntry	readLogEntry()
(package private) long	readLogUpdateIndex()
private PersonIdent	readPersonIdent()
(package private) long	readPositionFromIndex()
(package private) Ref	readRef(long minUpdateIndex)
(package private) long	readUpdateIndexDelta()
private ObjectId	readValueId()
private java.lang.String	readValueString()
private int	readVarint32()
private long	readVarint64()
private int	scanToKey(byte[] key, int rPtr, int rIdx, int rCmp)	Performs the linear search step within a restart interval.
(package private) int	seekKey(byte[] key)	Finds a key in the block and positions the current pointer on its record.
private void	setupEmptyFileBlock()
private void	skipString()
(package private) void	skipValue()
(package private) boolean	truncated()
(package private) byte	type()
(package private) void	verifyIndex()

Methods inherited from class java.lang.Object

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

Field Detail

blockType

private byte blockType

endPosition

private long endPosition

truncated

private boolean truncated

buf

private byte[] buf

bufLen

private int bufLen

ptr

private int ptr

keysStart

private int keysStart

keysEnd

private int keysEnd

restartCnt

private int restartCnt

restartTbl

private int restartTbl

nameBuf

private byte[] nameBuf

nameLen

private int nameLen

valueType

private int valueType

Constructor Detail

BlockReader

BlockReader()

Method Detail

type

byte type()

truncated

boolean truncated()

endPosition

long endPosition()

next

boolean next()

parseKey

void parseKey()

name

java.lang.String name()

match

boolean match(byte[] match,
              boolean matchIsPrefix)

readPositionFromIndex

long readPositionFromIndex()
                    throws java.io.IOException

Throws:

java.io.IOException

readUpdateIndexDelta

long readUpdateIndexDelta()

readRef

Ref readRef(long minUpdateIndex)
     throws java.io.IOException

Throws:

java.io.IOException

readBlockPositionList

@Nullable
LongList readBlockPositionList()

readLogUpdateIndex

long readLogUpdateIndex()

readLogEntry

@Nullable
ReflogEntry readLogEntry()

readValueId

private ObjectId readValueId()

readValueString

private java.lang.String readValueString()

readPersonIdent

private PersonIdent readPersonIdent()

readBlock

void readBlock(BlockSource src,
               long pos,
               int fileBlockSize)
        throws java.io.IOException

Throws:

java.io.IOException

readBlockIntoBuf

private void readBlockIntoBuf(BlockSource src,
                              long pos,
                              int size)
                       throws java.io.IOException

Throws:

java.io.IOException

parseBlockStart

private void parseBlockStart(BlockSource src,
                             long pos,
                             int fileBlockSize)
                      throws java.io.IOException

Throws:

java.io.IOException

decodeBlockLen

static int decodeBlockLen(int typeAndSize)

inflateBuf

private long inflateBuf(BlockSource src,
                        long pos,
                        int blockLen,
                        int fileBlockSize)
                 throws java.io.IOException

Throws:

java.io.IOException

setupEmptyFileBlock

private void setupEmptyFileBlock()

verifyIndex

void verifyIndex()
          throws java.io.IOException

Throws:

java.io.IOException

seekKey

int seekKey(byte[] key)

Finds a key in the block and positions the current pointer on its record.

As a side-effect this method arranges for the current pointer to be near or exactly on key, allowing other methods to access data from that current record:

• name()
• match(byte[], boolean)
• readRef(long)
• readLogUpdateIndex()
• readLogEntry()
• readBlockPositionList()

Parameters:

key - key to find.

Returns:

<0 if the key occurs before the start of this block; 0 if the block is positioned on the key; >0 if the key occurs after the last key of this block.

scanToKey

private int scanToKey(byte[] key,
                      int rPtr,
                      int rIdx,
                      int rCmp)

Performs the linear search step within a restart interval.

Starts at a restart position whose key sorts before (or equal to) key and walks sequentially through the following prefix compressed records to find key.

Parameters:

key - key the caller wants to find.

rPtr - current record pointer from restart table binary search.

rIdx - current restart table index.

rCmp - result of compare from restart table binary search.

Returns:

<0 if the key occurs before the start of this block; 0 if the block is positioned on the key; >0 if the key occurs after the last key of this block.

skipValue

void skipValue()

skipString

private void skipString()

readInt16

private short readInt16()

readVarint32

private int readVarint32()

readVarint64

private long readVarint64()

newRef

private static Ref newRef(java.lang.String name,
                          long updateIndex)

invalidBlock

private static java.io.IOException invalidBlock()

invalidBlock

private static java.io.IOException invalidBlock(java.lang.Throwable cause)