org.apache.labs.bananadb.store.data.bananatrie
Class Hashtable

java.lang.Object
  org.apache.labs.bananadb.store.data.FileHandler<Hashtable.Header,Hashtable.Posting>
      org.apache.labs.bananadb.store.data.bananatrie.Hashtable

public class Hashtable
extends FileHandler<Hashtable.Header,Hashtable.Posting>

Hashtable file. There is never more than one of these that are valid at any given time.

The position in the hashtable for a given hash code is calculated as (hash & (capacity - 1)). At this position there is a posting that points at the first known hash code posting.

This file is affected by rehashing.

Since:

2009-mar-16 14:00:56

Author:

kalle

Nested Class Summary

static class	Hashtable.Header
static class	Hashtable.Posting

Field Summary

static int

HEADER_BYTE_SIZE

Constructor Summary

Hashtable(java.io.File directory, int versionId, java.lang.String access, LockFactory lockFactory)

Method Summary

int	calculateHashCodePostingOffset(long hashCode)
int	getHeaderByteSize()
int	getVersionId()
void	markPostingAsDeleted(int startOffset, java.io.RandomAccessFile RAF, long revision)
void	open()
void	readHeader(Hashtable.Header header, java.io.RandomAccessFile RAF)
void	readPosting(Hashtable.Posting posting, java.io.RandomAccessFile RAF)
void	writeHeader(Hashtable.Header header, java.io.RandomAccessFile RAF)
void	writePosting(Hashtable.Posting posting, java.io.RandomAccessFile RAF)

Methods inherited from class org.apache.labs.bananadb.store.data.FileHandler

close, exists, format, format, getFile, getLock, getRAF, markPostingAsDeleted, readHeader, readHeader, readHeader, readPosting, readPosting, writeHeader, writeHeader, writeHeader, writePosting, writePosting, writePosting

Methods inherited from class java.lang.Object

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

Field Detail

HEADER_BYTE_SIZE

public static final int HEADER_BYTE_SIZE

See Also:

Constant Field Values

Constructor Detail

Hashtable

public Hashtable(java.io.File directory,
                 int versionId,
                 java.lang.String access,
                 LockFactory lockFactory)
          throws java.io.IOException

Throws:

java.io.IOException

Method Detail

open

public void open()
          throws java.io.IOException

Overrides:

open in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException

getVersionId

public int getVersionId()

getHeaderByteSize

public int getHeaderByteSize()

Specified by:

getHeaderByteSize in class FileHandler<Hashtable.Header,Hashtable.Posting>

readHeader

public void readHeader(Hashtable.Header header,
                       java.io.RandomAccessFile RAF)
                throws java.io.IOException

Specified by:

readHeader in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException

writeHeader

public void writeHeader(Hashtable.Header header,
                        java.io.RandomAccessFile RAF)
                 throws java.io.IOException

Specified by:

writeHeader in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException

calculateHashCodePostingOffset

public int calculateHashCodePostingOffset(long hashCode)

readPosting

public void readPosting(Hashtable.Posting posting,
                        java.io.RandomAccessFile RAF)
                 throws java.io.IOException

Specified by:

readPosting in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException

writePosting

public void writePosting(Hashtable.Posting posting,
                         java.io.RandomAccessFile RAF)
                  throws java.io.IOException

Specified by:

writePosting in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException

markPostingAsDeleted

public void markPostingAsDeleted(int startOffset,
                                 java.io.RandomAccessFile RAF,
                                 long revision)
                          throws java.io.IOException

Specified by:

markPostingAsDeleted in class FileHandler<Hashtable.Header,Hashtable.Posting>

Throws:

java.io.IOException