com.github.mjdev.libaums.driver.scsi

Class ScsiBlockDevice

java.lang.Object

com.github.mjdev.libaums.driver.scsi.ScsiBlockDevice

All Implemented Interfaces:

BlockDeviceDriver

public class ScsiBlockDevice
extends java.lang.Object
implements BlockDeviceDriver

This class is responsible for handling mass storage devices which follow the SCSI standard. This class communicates with the mass storage device via the different SCSI commands.

See Also:

com.github.mjdev.libaums.driver.scsi.commands

Constructor Summary

Constructors

Constructor and Description
ScsiBlockDevice(UsbCommunication usbCommunication)

Method Summary

Modifier and Type	Method and Description
int	getBlockSize() Returns the block size of the block device.
void	init() Issues a SCSI Inquiry to determine the connected device.
void	read(long devOffset, java.nio.ByteBuffer dest) This method reads from the device at the specific device offset.
void	write(long devOffset, java.nio.ByteBuffer src) This method writes from the device at the specific device offset.

Methods inherited from class java.lang.Object

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

Constructor Detail

ScsiBlockDevice

public ScsiBlockDevice(UsbCommunication usbCommunication)

Method Detail

init

public void init()
          throws java.io.IOException

Issues a SCSI Inquiry to determine the connected device. After that it is checked if the unit is ready. Logs a warning if the unit is not ready. Finally the capacity of the mass storage device is read.

Specified by:

init in interface BlockDeviceDriver

Throws:

java.io.IOException - If initialing fails due to an unsupported device or if reading fails.

See Also:

ScsiInquiry, ScsiInquiryResponse, ScsiTestUnitReady, ScsiReadCapacity, ScsiReadCapacityResponse

read

public void read(long devOffset,
                 java.nio.ByteBuffer dest)
          throws java.io.IOException

This method reads from the device at the specific device offset. The devOffset specifies at which block the reading should begin. That means the devOffset is not in bytes!

Specified by:

read in interface BlockDeviceDriver

Parameters:

devOffset - 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 devOffset,
                  java.nio.ByteBuffer src)
           throws java.io.IOException

This method writes from the device at the specific device offset. The devOffset specifies at which block the writing should begin. That means the devOffset is not in bytes!

Specified by:

write in interface BlockDeviceDriver

Parameters:

devOffset - 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.