org.apache.poi.poifs.storage
Class BATBlock

java.lang.Object
  org.apache.poi.poifs.storage.BATBlock

All Implemented Interfaces:

BlockWritable

public class BATBlock
extends java.lang.Object

A block of block allocation table entries. BATBlocks are created only through a static factory method: createBATBlocks.

Author:

Marc Johnson (mjohnson at apache dot org)

Method Summary

static int	calculateStorageRequirements(int entryCount) Calculate how many BATBlocks are needed to hold a specified number of BAT entries.
static int	calculateXBATStorageRequirements(int entryCount) Calculate how many XBATBlocks are needed to hold a specified number of BAT entries.
static BATBlock[]	createBATBlocks(int[] entries) Create an array of BATBlocks from an array of int block allocation table entries
static BATBlock[]	createXBATBlocks(int[] entries, int startBlock) Create an array of XBATBlocks from an array of int block allocation table entries
protected void	doWriteData(java.io.OutputStream stream, byte[] data) Default implementation of write for extending classes that contain their data in a simple array of bytes.
static int	entriesPerBlock()
static int	entriesPerXBATBlock()
static int	getXBATChainOffset()
void	writeBlocks(java.io.OutputStream stream) Write the storage to an OutputStream

Methods inherited from class java.lang.Object

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

Method Detail

createBATBlocks

public static BATBlock[] createBATBlocks(int[] entries)

Create an array of BATBlocks from an array of int block allocation table entries

Parameters:

entries - the array of int entries

Returns:

the newly created array of BATBlocks

createXBATBlocks

public static BATBlock[] createXBATBlocks(int[] entries,
                                          int startBlock)

Create an array of XBATBlocks from an array of int block allocation table entries

Parameters:

entries - the array of int entries

startBlock - the start block of the array of XBAT blocks

Returns:

the newly created array of BATBlocks

calculateStorageRequirements

public static int calculateStorageRequirements(int entryCount)

Calculate how many BATBlocks are needed to hold a specified number of BAT entries.

Parameters:

entryCount - the number of entries

Returns:

the number of BATBlocks needed

calculateXBATStorageRequirements

public static int calculateXBATStorageRequirements(int entryCount)

Calculate how many XBATBlocks are needed to hold a specified number of BAT entries.

Parameters:

entryCount - the number of entries

Returns:

the number of XBATBlocks needed

entriesPerBlock

public static final int entriesPerBlock()

Returns:

number of entries per block

entriesPerXBATBlock

public static final int entriesPerXBATBlock()

Returns:

number of entries per XBAT block

getXBATChainOffset

public static final int getXBATChainOffset()

Returns:

offset of chain index of XBAT block

doWriteData

protected void doWriteData(java.io.OutputStream stream,
                           byte[] data)
                    throws java.io.IOException

Default implementation of write for extending classes that contain their data in a simple array of bytes.

Parameters:

stream - the OutputStream to which the data should be written.

data - the byte array of to be written.

Throws:

java.io.IOException - on problems writing to the specified stream.

writeBlocks

public void writeBlocks(java.io.OutputStream stream)
                 throws java.io.IOException

Write the storage to an OutputStream

Specified by:

writeBlocks in interface BlockWritable

Parameters:

stream - the OutputStream to which the stored data should be written

Throws:

java.io.IOException - on problems writing to the specified stream