org.sejda.io

Interface SeekableSource

All Superinterfaces:

AutoCloseable, Channel, Closeable, ReadableByteChannel

All Known Implementing Classes:

BaseSeekableSource, BufferedSeekableSource, ByteArraySeekableSource, FileChannelSeekableSource, MemoryMappedSeekableSource

public interface SeekableSource
extends ReadableByteChannel

Readable source that provides random access capabilities.

Author:

Andrea Vacondio

Method Summary

Modifier and Type	Method and Description
default InputStream	asInputStream() Creates an InputStream from this SeekableSource.
default SeekableSource	back() Skips backward moving back the source position of one byte
default SeekableSource	back(long offset) Skips backward the given number of bytes moving back the source position
default SeekableSource	forward(long offset) Skips the given number of bytes moving forward the source position
String	id()
default int	peek() Reads the next byte and sets the position back by one.
default int	peekBack() Reads the previous byte and sets the position back where it was.
long	position()
SeekableSource	position(long position) Sets the source position.
int	read() Reads a byte of data from this source.
long	size()
SeekableSource	view(long startingPosition, long length)

Methods inherited from interface java.nio.channels.ReadableByteChannel

read

Methods inherited from interface java.nio.channels.Channel

close, isOpen

Method Detail

id

String id()

Returns:

the unique id for the source.

position

long position()
       throws IOException

Returns:

the current source position as a positive long

Throws:

IOException

position

SeekableSource position(long position)
                 throws IOException

Sets the source position. Setting the position to a value that is greater than the source's size is legal but does not change the size of the source. A later attempt to read bytes at such a position will immediately return an end-of-file indication.

Parameters:

position - a non-negative long for the new position

Returns:

this source

Throws:

IOException

size

long size()

Returns:

The source size, measured in bytes

read

int read()
  throws IOException

Reads a byte of data from this source. The byte is returned as an integer in the range 0 to 255 ( 0x00-0xff ).

Returns:

the next byte of data, or -1 if there is no more data.

Throws:

IOException

view

SeekableSource view(long startingPosition,
                    long length)
             throws IOException

Parameters:

startingPosition -

length -

Returns:

a readable view of a portion of this SeekableSource. Reading from the view doesn't affect the SeekableSource position. Closing the SeekableSource makes all the views unreadable but closing the view has no effect on the SeekableSource. A view may or may not work on a thread bound copy of the SeekableSource so as a general rule it should not be created and handed to other threads..

Throws:

IOException - if something goes wrong while creating the view

back

default SeekableSource back(long offset)
                     throws IOException

Skips backward the given number of bytes moving back the source position

Parameters:

offset - the number of bytes to skip back.

Returns:

this source

Throws:

IOException

back

default SeekableSource back()
                     throws IOException

Skips backward moving back the source position of one byte

Returns:

this source

Throws:

IOException

See Also:

back(long)

forward

default SeekableSource forward(long offset)
                        throws IOException

Skips the given number of bytes moving forward the source position

Parameters:

offset - the number of bytes to skip .

Returns:

this source

Throws:

IOException

peek

default int peek()
          throws IOException

Reads the next byte and sets the position back by one.

Returns:

the next byte or -1 if there is no more data.

Throws:

IOException

See Also:

read()

peekBack

default int peekBack()
              throws IOException

Reads the previous byte and sets the position back where it was.

Returns:

the previous byte or -1 if we are at the beginning of the source.

Throws:

IOException

See Also:

read()

asInputStream

default InputStream asInputStream()

Creates an InputStream from this SeekableSource.

Returns:

the input stream wrapping the given SeekableSource