Class SubInputStream

java.lang.Object

javax.imageio.stream.ImageInputStreamImpl

org.apache.pdfbox.jbig2.io.SubInputStream

All Implemented Interfaces:

Closeable, DataInput, AutoCloseable, ImageInputStream

public class SubInputStream
extends ImageInputStreamImpl

A wrapper for an ImageInputStream which is able to provide a view of a specific part of the wrapped stream. Read accesses to the wrapped stream are synchronized, so that users of this stream need to deal with synchronization against other users of the same instance, but not against other users of the wrapped stream.

Field Summary

Fields

Modifier and Type	Field	Description
private final byte[]	buffer	A buffer which is used to improve read performance.
(package private) long	bufferBase	Location of the first byte in the buffer with respect to the start of the stream.
(package private) long	bufferTop	Location of the last byte in the buffer with respect to the start of the stream.
protected final long	length	The length of the window.
protected final long	offset	The position in the wrapped stream at which the window starts.
protected final ImageInputStream	wrappedStream

Fields inherited from class ImageInputStreamImpl

bitOffset, byteOrder, flushedPos, streamPos

Constructor Summary

Constructors

Constructor	Description
SubInputStream(ImageInputStream iis, long offset, long length)	Construct a new SubInputStream which provides a view of the wrapped stream.

Method Summary

Modifier and Type	Method	Description
private boolean	fillBuffer()	Fill the buffer at the current stream position.
long	length()
int	read()
int	read(byte[] b, int off, int len)
void	skipBits()	Skips remaining bits in the current byte.

Methods inherited from class ImageInputStreamImpl

checkClosed, close, finalize, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, isCached, isCachedFile, isCachedMemory, mark, read, readBit, readBits, readBoolean, readByte, readBytes, readChar, readDouble, readFloat, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort, readUTF, reset, seek, setBitOffset, setByteOrder, skipBytes, skipBytes

Methods inherited from class Object

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

Field Details

wrappedStream

protected final ImageInputStream wrappedStream

offset

protected final long offset

The position in the wrapped stream at which the window starts. Offset is an absolut value.

length

protected final long length

The length of the window. Length is an relative value.

buffer

private final byte[] buffer

A buffer which is used to improve read performance.

bufferBase

long bufferBase

Location of the first byte in the buffer with respect to the start of the stream.

bufferTop

long bufferTop

Location of the last byte in the buffer with respect to the start of the stream.

Constructor Details

SubInputStream

public SubInputStream(ImageInputStream iis,
 long offset,
 long length)

Construct a new SubInputStream which provides a view of the wrapped stream.

Parameters:

iis - - The stream to be wrapped.

offset - - The absolute position in the wrapped stream at which the sub-stream starts.

length - - The length of the sub-stream.

Method Details

read

public int read()
         throws IOException

Specified by:

read in interface ImageInputStream

Specified by:

read in class ImageInputStreamImpl

Throws:

IOException

read

public int read(byte[] b,
 int off,
 int len)
         throws IOException

Specified by:

read in interface ImageInputStream

Specified by:

read in class ImageInputStreamImpl

Throws:

IOException

fillBuffer

private boolean fillBuffer()
                    throws IOException

Fill the buffer at the current stream position.

Returns:

Boolean flag. true if successful, false if not.

Throws:

IOException

length

public long length()

Specified by:

length in interface ImageInputStream

Overrides:

length in class ImageInputStreamImpl

skipBits

public void skipBits()

Skips remaining bits in the current byte.