Class MemoryCacheSeekableStream.MemoryCache

java.lang.Object

com.twelvemonkeys.io.AbstractCachedSeekableStream.StreamCache

com.twelvemonkeys.io.MemoryCacheSeekableStream.MemoryCache

Enclosing class:

MemoryCacheSeekableStream

static final class MemoryCacheSeekableStream.MemoryCache
extends AbstractCachedSeekableStream.StreamCache

Version:

$Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/io/MemoryCacheSeekableStream.java#3 $

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final int	BLOCK_SIZE
private final List<byte[]>	cache
private long	length
private long	position
private long	start

Constructor Summary

Constructors

Constructor	Description
MemoryCache()

Method Summary

Modifier and Type	Method	Description
(package private) void	close()
void	flush(long pPosition)	Optionally flushes any data prior to the given position.
private byte[]	getBlock()
long	getPosition()	Returns the current cache read/write position.
int	read()	Reads a single byte a the current read/write position.
int	read(byte[] pBytes, int pOffset, int pLength)	Writes a series of bytes at the current read/write position.
void	seek(long pPosition)	Repositions the current cache read/write position to the given position.
void	write(byte[] pBuffer, int pOffset, int pLength)	Writes a series of bytes at the current read/write position.
void	write(int pByte)	Writes a single byte at the current read/write position.

Methods inherited from class Object

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

Field Details

BLOCK_SIZE

static final int BLOCK_SIZE

See Also:

• Constant Field Values

cache

private final List<byte[]> cache

length

private long length

position

private long position

start

private long start

Constructor Details

MemoryCache

MemoryCache()

Method Details

getBlock

private byte[] getBlock()
                 throws IOException

Throws:

IOException

write

public void write(int pByte)
           throws IOException

Description copied from class: AbstractCachedSeekableStream.StreamCache

Writes a single byte at the current read/write position. The read/write position will be increased by one.

Specified by:

write in class AbstractCachedSeekableStream.StreamCache

Parameters:

pByte - the byte value to write.

Throws:

IOException - if an I/O exception occurs in the cache backing mechanism.

write

public void write(byte[] pBuffer,
 int pOffset,
 int pLength)
           throws IOException

Description copied from class: AbstractCachedSeekableStream.StreamCache

Writes a series of bytes at the current read/write position. The read/write position will be increased by pLength.

This implementation invokes AbstractCachedSeekableStream.StreamCache.write(int) pLength times. Subclasses may override this method for performance.

Overrides:

write in class AbstractCachedSeekableStream.StreamCache

Parameters:

pBuffer - the bytes to write.

pOffset - the starting offset into the buffer.

pLength - the number of bytes to write from the buffer.

Throws:

IOException - if an I/O exception occurs in the cache backing mechanism.

read

public int read()
         throws IOException

Description copied from class: AbstractCachedSeekableStream.StreamCache

Reads a single byte a the current read/write position. The read/write position will be increased by one.

Specified by:

read in class AbstractCachedSeekableStream.StreamCache

Returns:

the value read, or -1 to indicate EOF.

Throws:

IOException - if an I/O exception occurs in the cache backing mechanism.

read

public int read(byte[] pBytes,
 int pOffset,
 int pLength)
         throws IOException

Description copied from class: AbstractCachedSeekableStream.StreamCache

Writes a series of bytes at the current read/write position. The read/write position will be increased by pLength.

This implementation invokes AbstractCachedSeekableStream.StreamCache.read() pLength times. Subclasses may override this method for performance.

Overrides:

read in class AbstractCachedSeekableStream.StreamCache

Parameters:

pBytes - the bytes to write

pOffset - the starting offset into the buffer.

pLength - the number of bytes to write from the buffer.

Returns:

the number of bytes read, or -1 to indicate EOF.

Throws:

IOException - if an I/O exception occurs in the cache backing mechanism.

seek

public void seek(long pPosition)
          throws IOException

Description copied from class: AbstractCachedSeekableStream.StreamCache

Repositions the current cache read/write position to the given position.

Specified by:

seek in class AbstractCachedSeekableStream.StreamCache

Parameters:

pPosition - the new read/write position

Throws:

IOException - if an I/O exception occurs in the cache backing mechanism.

flush

public void flush(long pPosition)

Description copied from class: AbstractCachedSeekableStream.StreamCache

Optionally flushes any data prior to the given position.

Attempting to perform a seek operation, and/or a read or write operation to a position equal to or before the flushed position may result in exceptions or undefined behaviour.

Subclasses should override this method for performance reasons, to avoid holding on to unnecessary resources. This implementation does nothing.

Overrides:

flush in class AbstractCachedSeekableStream.StreamCache

Parameters:

pPosition - the last position to flush.

close

void close()
    throws IOException

Specified by:

close in class AbstractCachedSeekableStream.StreamCache

Throws:

IOException

getPosition

public long getPosition()

Description copied from class: AbstractCachedSeekableStream.StreamCache

Returns the current cache read/write position.

Specified by:

getPosition in class AbstractCachedSeekableStream.StreamCache

Returns:

the current cache read/write postion.