net.bitform.api

Interface SimpleChannel

All Known Implementing Classes:

NativeSimpleChannel

public interface SimpleChannel

Interface that allows the developer to provide read and/or write access to an series of bytes. Classes that implement this interface may be passed to the options of type FileOption, most commonly the SecureOptions.SourceDocument, SecureOptions.ScrubbedDocument and SecureOptions.ResultDocument options.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DIRECTBYTEBUFFERS Indicates the SimpleChannel requires direct ByteBuffers to operate correctly.
static int	READ Indicates the SimpleChannel supports reading bytes.
static int	READWRITE Indicates the SimpleChannel supports both reading and writing bytes.
static int	WRITE Indicates the SimpleChannel supports writing bytes.

Method Summary

Modifier and Type	Method and Description
void	close() Close resources associated with this SimpleChannel
int	read(java.nio.ByteBuffer buffer, long position) Read bytes into the buffer from the developer's bytes.
long	size() The size of the developer's bytes.
int	supports() Return what operations the SimpleChannel supports
void	truncate(long size) Truncate the stream to the given length.
void	write(java.nio.ByteBuffer buffer, long position) Writes bytes from the buffer to the developer's bytes.

Field Detail

READ

static final int READ

Indicates the SimpleChannel supports reading bytes.

See Also:

Constant Field Values

WRITE

static final int WRITE

Indicates the SimpleChannel supports writing bytes.

See Also:

Constant Field Values

READWRITE

static final int READWRITE

Indicates the SimpleChannel supports both reading and writing bytes.

See Also:

Constant Field Values

DIRECTBYTEBUFFERS

static final int DIRECTBYTEBUFFERS

Indicates the SimpleChannel requires direct ByteBuffers to operate correctly.

See Also:

Constant Field Values

Method Detail

read

int read(java.nio.ByteBuffer buffer,
         long position)
  throws java.io.IOException

Read bytes into the buffer from the developer's bytes. Up to buffer.remaining bytes should to read into the buffer starting at buffer.position and continuing until either buffer.limit or the underlying byte stream runs out of bytes. Reading beyond bounds of the developer's bytes stream must NOT throw an EOFException.

Parameters:

buffer - Target buffer for the read bytes

position - Location in the underlying byte stream where the method should being reading bytes

Returns:

Number of bytes actually read, may be 0 or -1 if there are no more bytes to read

Throws:

java.io.IOException - Any failure to read

write

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

Writes bytes from the buffer to the developer's bytes. buffer.remaining bytes should be written starting at buffer.position and continuing until buffer.limit.

Parameters:

buffer -

position - Location in the underlying byte stream where the method should being writing bytes

Throws:

java.io.IOException - Any failure to write

size

long size()
   throws java.io.IOException

The size of the developer's bytes. Note that unlike some size methods a return value of -1 indicating that the size is unknown is not acceptable. Many file formats (most notablly PDF) cannot be processed unless the size is known.

Returns:

Number of bytes in the developer's byte stream.

Throws:

java.io.IOException - Any failure to get the size

supports

int supports()

Return what operations the SimpleChannel supports

Returns:

SimpleChannel.READ, SimpleChannel.WRITE or SimpleChannel.READWRITE possibly ORed with SimpleChannel.DIRECTBYTEBUFFERS

truncate

void truncate(long size)
       throws java.io.IOException

Truncate the stream to the given length. File position will be preserved unless it is beyond the new size in which case it will be reset to the last position.

Parameters:

size - Size of the file after truncation.

Throws:

java.io.IOException

close

void close()

Close resources associated with this SimpleChannel