com.github.mjdev.libaums.partition

Class Partition

java.lang.Object

com.github.mjdev.libaums.partition.Partition

All Implemented Interfaces:

BlockDeviceDriver

public class Partition
extends java.lang.Object
implements BlockDeviceDriver

This class represents a partition on an mass storage device. A partition has a certain file system which can be accessed via getFileSystem(). This file system is needed to to access the files and directories of a partition.

The method getVolumeLabel() returns the volume label for the partition. Calling the method is equivalent to calling FileSystem.getVolumeLabel().

Method Summary

Modifier and Type	Method and Description
static Partition	createPartition(PartitionTableEntry entry, BlockDeviceDriver blockDevice) Creates a new partition with the information given.
int	getBlockSize() Returns the block size of the block device.
FileSystem	getFileSystem()
java.lang.String	getVolumeLabel() This method returns the volume label of the file system / partition.
void	init() Initializes the block device for further use.
void	read(long offset, java.nio.ByteBuffer dest) Reads from the block device at a certain offset into the given buffer.
void	write(long offset, java.nio.ByteBuffer src) 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

Method Detail

createPartition

public static Partition createPartition(PartitionTableEntry entry,
                                        BlockDeviceDriver blockDevice)
                                 throws java.io.IOException

Creates a new partition with the information given.

Parameters:

entry - The entry the partition shall represent.

blockDevice - The underlying block device.

Returns:

The newly created Partition.

Throws:

java.io.IOException - If reading from the device fails.

getFileSystem

public FileSystem getFileSystem()

Returns:

the file system on the partition which can be used to access files and directories.

getVolumeLabel

public java.lang.String getVolumeLabel()

This method returns the volume label of the file system / partition. Calling this method is equivalent to calling FileSystem.getVolumeLabel().

Returns:

Returns the volume label of this partition.

init

public void init()

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

read

public void read(long offset,
                 java.nio.ByteBuffer dest)
          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:

offset - The offset where the reading should begin.

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

Throws:

java.io.IOException - If reading fails.

write

public void write(long offset,
                  java.nio.ByteBuffer src)
           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:

offset - The offset where the writing should begin.

src - 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.