org.exist.storage.btree
Class Paged

java.lang.Object
  org.exist.storage.btree.Paged

Direct Known Subclasses:

BTree

public abstract class Paged
extends Object

Paged is a paged file foundation that is used by the BTree class and its subclasses.

Nested Class Summary

class	Paged.FileHeader FileHeader
class	Paged.Page Page
static class	Paged.PageHeader

Field Summary

static int	LENGTH_FIRST_FREE_PAGE
static int	LENGTH_HEADER_SIZE
static int	LENGTH_LAST_FREE_PAGE
static int	LENGTH_MAX_KEY_SIZE
static int	LENGTH_PAGE_COUNT
static int	LENGTH_PAGE_HEADER_SIZE
static int	LENGTH_PAGE_SIZE
static int	LENGTH_RECORD_COUNT
static int	LENGTH_TOTAL_COUNT
static int	LENGTH_VERSION_ID
static int	OFFSET_FIRST_FREE_PAGE
static int	OFFSET_HEADER_SIZE
static int	OFFSET_LAST_FREE_PAGE
static int	OFFSET_MAX_KEY_SIZE
static int	OFFSET_PAGE_COUNT
static int	OFFSET_PAGE_HEADER_SIZE
static int	OFFSET_PAGE_SIZE
static int	OFFSET_RECORD_COUNT
static int	OFFSET_REMAINDER
static int	OFFSET_TOTAL_COUNT
static int	OFFSET_VERSION_ID

Constructor Summary

Paged()

Paged(File file)

Method Summary

void	backupToStream(OutputStream os) Backup the entire contents of the underlying file to an output stream.
boolean	close() Close the underlying files.
void	closeAndRemove() Completely close down the instance and all underlying resources and caches.
boolean	create()
abstract Paged.FileHeader	createFileHeader() createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.
abstract Paged.FileHeader	createFileHeader(boolean read) createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.
abstract Paged.FileHeader	createFileHeader(long pageCount) createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.
abstract Paged.FileHeader	createFileHeader(long pageCount, int pageSize) createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.
abstract Paged.PageHeader	createPageHeader() createPageHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a PageHeader.
boolean	exists()
boolean	flush()
File	getFile() getFile returns the file object for this Paged.
Paged.FileHeader	getFileHeader() getFileHeader returns the FileHeader
abstract short	getFileVersion()
static int	getPageSize()
static String	hexDump(byte[] data)
boolean	isOpened() Gets the opened attribute of the Paged object
boolean	isReadOnly()
boolean	open(short expectedVersion)
void	printFreeSpaceList() Debug
static void	setPageSize(int pageSize)

Methods inherited from class java.lang.Object

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

Field Detail

LENGTH_VERSION_ID

public static int LENGTH_VERSION_ID

LENGTH_HEADER_SIZE

public static int LENGTH_HEADER_SIZE

LENGTH_PAGE_COUNT

public static int LENGTH_PAGE_COUNT

LENGTH_PAGE_SIZE

public static int LENGTH_PAGE_SIZE

LENGTH_TOTAL_COUNT

public static int LENGTH_TOTAL_COUNT

LENGTH_FIRST_FREE_PAGE

public static int LENGTH_FIRST_FREE_PAGE

LENGTH_LAST_FREE_PAGE

public static int LENGTH_LAST_FREE_PAGE

LENGTH_PAGE_HEADER_SIZE

public static int LENGTH_PAGE_HEADER_SIZE

LENGTH_MAX_KEY_SIZE

public static int LENGTH_MAX_KEY_SIZE

LENGTH_RECORD_COUNT

public static int LENGTH_RECORD_COUNT

OFFSET_VERSION_ID

public static int OFFSET_VERSION_ID

OFFSET_HEADER_SIZE

public static int OFFSET_HEADER_SIZE

OFFSET_PAGE_SIZE

public static int OFFSET_PAGE_SIZE

OFFSET_PAGE_COUNT

public static int OFFSET_PAGE_COUNT

OFFSET_TOTAL_COUNT

public static int OFFSET_TOTAL_COUNT

OFFSET_FIRST_FREE_PAGE

public static int OFFSET_FIRST_FREE_PAGE

OFFSET_LAST_FREE_PAGE

public static int OFFSET_LAST_FREE_PAGE

OFFSET_PAGE_HEADER_SIZE

public static int OFFSET_PAGE_HEADER_SIZE

OFFSET_MAX_KEY_SIZE

public static int OFFSET_MAX_KEY_SIZE

OFFSET_RECORD_COUNT

public static int OFFSET_RECORD_COUNT

OFFSET_REMAINDER

public static int OFFSET_REMAINDER

Constructor Detail

Paged

public Paged()

Paged

public Paged(File file)
      throws DBException

Throws:

DBException

Method Detail

getFileVersion

public abstract short getFileVersion()

setPageSize

public static final void setPageSize(int pageSize)

getPageSize

public static final int getPageSize()

isReadOnly

public final boolean isReadOnly()

close

public boolean close()
              throws DBException

Close the underlying files.

Returns:

TRUE if closed.

Throws:

DBException

create

public boolean create()
               throws DBException

Throws:

DBException

createFileHeader

public abstract Paged.FileHeader createFileHeader()

createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.

Returns:

a new FileHeader

createFileHeader

public abstract Paged.FileHeader createFileHeader(boolean read)
                                           throws IOException

createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.

Parameters:

read - If true, reads the FileHeader from disk

Returns:

a new FileHeader

Throws:

IOException - if an exception occurs

createFileHeader

public abstract Paged.FileHeader createFileHeader(long pageCount)

createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.

Parameters:

pageCount - The number of pages to allocate for primary storage

Returns:

a new FileHeader

createFileHeader

public abstract Paged.FileHeader createFileHeader(long pageCount,
                                                  int pageSize)

createFileHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a FileHeader.

Parameters:

pageCount - The number of pages to allocate for primary storage

pageSize - The size of a Page (should be a multiple of a FS block)

Returns:

a new FileHeader

createPageHeader

public abstract Paged.PageHeader createPageHeader()

createPageHeader must be implemented by a Paged implementation in order to create an appropriate subclass instance of a PageHeader.

Returns:

a new PageHeader

exists

public boolean exists()

flush

public boolean flush()
              throws DBException

Throws:

DBException

backupToStream

public void backupToStream(OutputStream os)
                    throws IOException

Backup the entire contents of the underlying file to an output stream.

Parameters:

os -

Throws:

IOException

getFile

public final File getFile()

getFile returns the file object for this Paged.

Returns:

The File

getFileHeader

public Paged.FileHeader getFileHeader()

getFileHeader returns the FileHeader

Returns:

The FileHeader

closeAndRemove

public void closeAndRemove()

Completely close down the instance and all underlying resources and caches.

isOpened

public boolean isOpened()

Gets the opened attribute of the Paged object

Returns:

The opened value

open

public boolean open(short expectedVersion)
             throws DBException

Throws:

DBException

printFreeSpaceList

public void printFreeSpaceList()
                        throws IOException

Debug

Throws:

IOException - Description of the Exception

hexDump

public static String hexDump(byte[] data)