com.caucho.db.store
Class Inode

java.lang.Object
  com.caucho.db.store.Inode

public class Inode
extends java.lang.Object

Represents the indexes for a BLOB or CLOB. The inode contains 16 long values

  0) length of the saved file
  1-14) direct fragment addresses (to 112k)
  15) pointer to the indirect block
 

Inline storage (120)

If the length of the blob is less than 120, the blob is stored directly in the inode.

mini fragment storage (3840)

If the length of the blob is less than 3840, the blob is stored in mini-fragments of size 256 pointed by the inode's addresses. The maximum wasted space for mini-fragment storage is 255 bytes.

indirect storage

The indirect block (an 8k fragment) itself is divided into sections:

  0-511) single indirect fragment addresses (4M, 2^12)
  512-767) double indirect block addresses (128G, 2^37)
  768-1023) triple indirect fragment addresses (to 1P, 2^50)
 

Field Summary

static int	BLOCK_SIZE
static int	DIRECT_BLOCKS
static long	DIRECT_MAX
static int	DOUBLE_INDIRECT_BLOCKS
static long	DOUBLE_INDIRECT_MAX
static long	FRAGMENT_MAX
static int	FRAGMENT_SIZE
static int	INDIRECT_BLOCKS
static int	INLINE_BLOB_SIZE
static long	INLINE_MAX
static int	INODE_BLOCK_SIZE
static int	INODE_SIZE
static int	MINI_FRAG_BLOB_SIZE
static int	MINI_FRAG_MAX
static int	MINI_FRAG_SIZE
static int	SINGLE_INDIRECT_BLOCKS
static long	SINGLE_INDIRECT_MAX
static int	TRIPLE_INDIRECT_BLOCKS

Constructor Summary

Inode()

Inode(Store store)

Inode(Store store, StoreTransaction xa)

Method Summary

byte[]	getBuffer() Returns the buffer.
long	getLength() Returns the length.
Store	getStore() Returns the backing store.
void	init(Store store, StoreTransaction xa, byte[] buffer, int offset)
java.io.InputStream	openInputStream() Opens a read stream to the inode.
java.io.OutputStream	openOutputStream() Opens a byte output stream to the inode.
java.io.Reader	openReader() Opens a char reader to the inode.
java.io.Writer	openWriter() Opens a char writer to the inode.
static long	readLong(byte[] buffer, int offset) Reads the long.
void	remove() Deletes the inode
static void	writeLong(byte[] buffer, int offset, long v) Writes the long.
void	writeToStream(OutputStreamWithBuffer os) Writes the inode value to a stream.
void	writeToStream(OutputStreamWithBuffer os, long offset, long length) Writes the inode value to a stream.
void	writeToWriter(java.io.Writer writer) Writes the inode value to a stream.

Methods inherited from class java.lang.Object

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

Field Detail

INODE_SIZE

public static final int INODE_SIZE

See Also:

Constant Field Values

INLINE_BLOB_SIZE

public static final int INLINE_BLOB_SIZE

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Constant Field Values

BLOCK_SIZE

public static final int BLOCK_SIZE

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Constant Field Values

INODE_BLOCK_SIZE

public static final int INODE_BLOCK_SIZE

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Constant Field Values

FRAGMENT_SIZE

public static final int FRAGMENT_SIZE

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Constant Field Values

MINI_FRAG_SIZE

public static final int MINI_FRAG_SIZE

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Constant Field Values

MINI_FRAG_BLOB_SIZE

public static final int MINI_FRAG_BLOB_SIZE

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Constant Field Values

INDIRECT_BLOCKS

public static final int INDIRECT_BLOCKS

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Constant Field Values

DIRECT_BLOCKS

public static final int DIRECT_BLOCKS

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Constant Field Values

SINGLE_INDIRECT_BLOCKS

public static final int SINGLE_INDIRECT_BLOCKS

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Constant Field Values

DOUBLE_INDIRECT_BLOCKS

public static final int DOUBLE_INDIRECT_BLOCKS

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Constant Field Values

TRIPLE_INDIRECT_BLOCKS

public static final int TRIPLE_INDIRECT_BLOCKS

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Constant Field Values

INLINE_MAX

public static final long INLINE_MAX

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Constant Field Values

MINI_FRAG_MAX

public static final int MINI_FRAG_MAX

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Constant Field Values

DIRECT_MAX

public static final long DIRECT_MAX

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Constant Field Values

SINGLE_INDIRECT_MAX

public static final long SINGLE_INDIRECT_MAX

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Constant Field Values

FRAGMENT_MAX

public static final long FRAGMENT_MAX

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Constant Field Values

DOUBLE_INDIRECT_MAX

public static final long DOUBLE_INDIRECT_MAX

See Also:

Constant Field Values

Constructor Detail

Inode

public Inode()

Inode

public Inode(Store store,
             StoreTransaction xa)

Inode

public Inode(Store store)

Method Detail

getStore

public Store getStore()

Returns the backing store.

getBuffer

public byte[] getBuffer()

Returns the buffer.

getLength

public long getLength()

Returns the length.

init

public void init(Store store,
                 StoreTransaction xa,
                 byte[] buffer,
                 int offset)

openInputStream

public java.io.InputStream openInputStream()

Opens a read stream to the inode.

writeToStream

public void writeToStream(OutputStreamWithBuffer os)
                   throws java.io.IOException

Writes the inode value to a stream.

Throws:

java.io.IOException

writeToStream

public void writeToStream(OutputStreamWithBuffer os,
                          long offset,
                          long length)
                   throws java.io.IOException

Writes the inode value to a stream.

Throws:

java.io.IOException

writeToWriter

public void writeToWriter(java.io.Writer writer)
                   throws java.io.IOException

Writes the inode value to a stream.

Throws:

java.io.IOException

openOutputStream

public java.io.OutputStream openOutputStream()

Opens a byte output stream to the inode.

openReader

public java.io.Reader openReader()

Opens a char reader to the inode.

openWriter

public java.io.Writer openWriter()

Opens a char writer to the inode.

remove

public void remove()

Deletes the inode

readLong

public static long readLong(byte[] buffer,
                            int offset)

Reads the long.

writeLong

public static void writeLong(byte[] buffer,
                             int offset,
                             long v)

Writes the long.