Package com.github.mjdev.libaums.driver.file

Class FileBlockDeviceDriver

java.lang.Object

com.github.mjdev.libaums.driver.file.FileBlockDeviceDriver

All Implemented Interfaces:

BlockDeviceDriver

public class FileBlockDeviceDriver
extends java.lang.Object
implements BlockDeviceDriver

Created by magnusja on 01/08/17.

Constructor Summary

Constructors

Constructor	Description
FileBlockDeviceDriver(java.io.File file)
FileBlockDeviceDriver(java.io.File file, int byteOffset)
FileBlockDeviceDriver(java.io.File file, int blockSize, int byteOffset)
FileBlockDeviceDriver(java.net.URL url)
FileBlockDeviceDriver(java.net.URL url, int byteOffset)
FileBlockDeviceDriver(java.net.URL url, int blockSize, int byteOffset)

Method Summary

Modifier and Type	Method	Description
int	getBlockSize()	Returns the block size of the block device.
void	init()	Initializes the block device for further use.
void	read(long deviceOffset, java.nio.ByteBuffer buffer)	Reads from the block device at a certain offset into the given buffer.
void	write(long deviceOffset, java.nio.ByteBuffer buffer)	Writes to the block device at a certain offset from the given buffer.

Methods inherited from class java.lang.Object

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

Constructor Detail

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.io.File file,
                             int blockSize,
                             int byteOffset)
                      throws java.io.FileNotFoundException

Throws:

java.io.FileNotFoundException

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.io.File file,
                             int byteOffset)
                      throws java.io.FileNotFoundException

Throws:

java.io.FileNotFoundException

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.io.File file)
                      throws java.io.FileNotFoundException

Throws:

java.io.FileNotFoundException

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.net.URL url,
                             int blockSize,
                             int byteOffset)
                      throws java.io.IOException

Throws:

java.io.IOException

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.net.URL url,
                             int byteOffset)
                      throws java.io.IOException

Throws:

java.io.IOException

FileBlockDeviceDriver

public FileBlockDeviceDriver(java.net.URL url)
                      throws java.io.IOException

Throws:

java.io.IOException

Method Detail

init

public void init()
          throws java.io.IOException

Description copied from interface: BlockDeviceDriver

Initializes the block device for further use. This method should be called before doing anything else on the block device.

Specified by:

init in interface BlockDeviceDriver

Throws:

java.io.IOException - If initializing fails

read

public void read(long deviceOffset,
                 java.nio.ByteBuffer buffer)
          throws java.io.IOException

Description copied from interface: BlockDeviceDriver

Reads from the block device at a certain offset into the given buffer. The amount of bytes to be read are determined by Buffer.remaining().

The deviceOffset can either be the amount of bytes or a logical block addressing using the block size. To get the bytes in the last case you have to multiply the lba with the block size (offset * BlockDeviceDriver.getBlockSize()).

Specified by:

read in interface BlockDeviceDriver

Parameters:

deviceOffset - The offset where the reading should begin.

buffer - The buffer where the data should be read into.

Throws:

java.io.IOException - If reading fails.

write

public void write(long deviceOffset,
                  java.nio.ByteBuffer buffer)
           throws java.io.IOException

Description copied from interface: BlockDeviceDriver

Writes to the block device at a certain offset from the given buffer. The amount of bytes to be written are determined by Buffer.remaining().

The deviceOffset can either be the amount of bytes or a logical block addressing using the block size. To get the bytes in the last case you have to multiply the lba with the block size (offset * BlockDeviceDriver.getBlockSize()).

Specified by:

write in interface BlockDeviceDriver

Parameters:

deviceOffset - The offset where the writing should begin.

buffer - The buffer with the data to be transferred.

Throws:

java.io.IOException - If writing fails.

getBlockSize

public int getBlockSize()

Description copied from interface: BlockDeviceDriver

Returns the block size of the block device. Every block device can only read and store bytes in a specific block with a certain size.

That means that it is only possible to read or write hole blocks!

Specified by:

getBlockSize in interface BlockDeviceDriver

Returns:

The block size in bytes, mostly 512 bytes.