bt.data.file

Class FileSystemStorageUnit

java.lang.Object

bt.data.file.FileSystemStorageUnit

All Implemented Interfaces:

StorageUnit, Closeable, AutoCloseable

public class FileSystemStorageUnit
extends Object
implements StorageUnit

Constructor Summary

Constructors

Constructor and Description
FileSystemStorageUnit(OpenFileCache cache, Path file)

Method Summary

Modifier and Type	Method and Description
long	capacity() Get total maximum capacity of this storage.
void	close()
int	readBlock(ByteBuffer buffer, long offset) Try to read a block of data into the provided buffer, starting with a given offset.
void	readBlockFully(ByteBuffer buffer, long offset)
long	size() Get current amount of data in this storage.
String	toString()
int	writeBlock(ByteBuffer buffer, long offset) Try to write a block of data from the provided buffer to this storage, starting with a given offset.
int	writeBlock(ByteBufferView buffer, long offset) Try to write a block of data from the provided buffer to this storage, starting with a given offset.
void	writeBlockFully(ByteBuffer buffer, long offset)
void	writeBlockFully(ByteBufferView buffer, long offset)

Methods inherited from class java.lang.Object

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

Methods inherited from interface bt.data.StorageUnit

createEmpty, readBlock, writeBlock

Constructor Detail

FileSystemStorageUnit

public FileSystemStorageUnit(OpenFileCache cache,
                             Path file)

Method Detail

readBlock

public int readBlock(ByteBuffer buffer,
                     long offset)

Description copied from interface: StorageUnit

Try to read a block of data into the provided buffer, starting with a given offset. Maximum number of bytes to be read is determined by Buffer.remaining().

Storage must throw an exception if

offset > StorageUnit.capacity() - buffer.remaining()

Specified by:

readBlock in interface StorageUnit

Parameters:

buffer - Buffer to read bytes into. Value returned by buffer.remaining() determines the maximum number of bytes to read.

offset - Index to start reading from (0-based)

Returns:

Actual number of bytes read

readBlockFully

public void readBlockFully(ByteBuffer buffer,
                           long offset)

Specified by:

readBlockFully in interface StorageUnit

writeBlock

public int writeBlock(ByteBuffer buffer,
                      long offset)

Description copied from interface: StorageUnit

Try to write a block of data from the provided buffer to this storage, starting with a given offset.

Maximum number of bytes to be written is determined by Buffer.remaining().

Storage must throw an exception if

offset > StorageUnit.capacity() - buffer.remaining()

Specified by:

writeBlock in interface StorageUnit

Parameters:

buffer - Buffer containing the block of data to write to this storage. Value returned by buffer.remaining() determines the maximum number of bytes to write.

offset - Offset in this storage's data to start writing to (0-based)

Returns:

Actual number of bytes written

writeBlockFully

public void writeBlockFully(ByteBuffer buffer,
                            long offset)

Specified by:

writeBlockFully in interface StorageUnit

writeBlock

public int writeBlock(ByteBufferView buffer,
                      long offset)

Description copied from interface: StorageUnit

Try to write a block of data from the provided buffer to this storage, starting with a given offset.

Maximum number of bytes to be written is determined by ByteBufferView.remaining().

Storage must throw an exception if

offset > StorageUnit.capacity() - buffer.remaining()

Specified by:

writeBlock in interface StorageUnit

Parameters:

buffer - Buffer containing the block of data to write to this storage. Value returned by buffer.remaining() determines the maximum number of bytes to write.

offset - Offset in this storage's data to start writing to (0-based)

Returns:

Actual number of bytes written

writeBlockFully

public void writeBlockFully(ByteBufferView buffer,
                            long offset)

Specified by:

writeBlockFully in interface StorageUnit

capacity

public long capacity()

Description copied from interface: StorageUnit

Get total maximum capacity of this storage.

Specified by:

capacity in interface StorageUnit

Returns:

Total maximum capacity of this storage

size

public long size()

Description copied from interface: StorageUnit

Get current amount of data in this storage.

Specified by:

size in interface StorageUnit

Returns:

Current amount of data in this storage

toString

public String toString()

Overrides:

toString in class Object

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException