org.apache.pdfbox.io

Class RandomAccessReadBuffer

java.lang.Object

org.apache.pdfbox.io.RandomAccessReadBuffer

All Implemented Interfaces:

Closeable, AutoCloseable, RandomAccessRead

Direct Known Subclasses:

RandomAccessReadWriteBuffer

public class RandomAccessReadBuffer
extends Object
implements RandomAccessRead

An implementation of the RandomAccessRead interface to store data in memory. The data will be stored in chunks organized in an ArrayList.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	chunkSize
protected ByteBuffer	currentBuffer
protected int	currentBufferPointer
static int	DEFAULT_CHUNK_SIZE_4KB
protected long	pointer
protected long	size

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RandomAccessReadBuffer() Default constructor.
	RandomAccessReadBuffer(byte[] input) Create a random access buffer using the given byte array.
	RandomAccessReadBuffer(ByteBuffer input) Create a random access buffer using the given ByteBuffer.
	RandomAccessReadBuffer(InputStream input) Create a random access read buffer of the given input stream by copying the data to the memory.
protected	RandomAccessReadBuffer(int definedChunkSize) Default constructor.

Method Summary

Modifier and Type	Method and Description
protected void	checkClosed() Ensure that the RandomAccessBuffer is not closed
void	close()
static RandomAccessReadBuffer	createBufferFromStream(InputStream inputStream) Create e new RandomAccessReadBuffer using the given InputStream.
RandomAccessReadView	createView(long startPosition, long streamLength) Creates a random access read view starting at the given position with the given length.
protected void	expandBuffer() create a new buffer chunk and adjust all pointers and indices.
long	getPosition() Returns offset of next byte to be returned by a read method.
boolean	isClosed() Returns true if this source has been closed.
boolean	isEOF() A simple test to see if we are at the end of the data.
long	length() The total number of bytes that are available.
int	read() Read a single byte of data.
int	read(byte[] b, int offset, int length) Read a buffer of data.
protected void	resetBuffers() Reset to position 0 and remove all buffers but the first one.
void	seek(long position) Seek to a position in the data.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.pdfbox.io.RandomAccessRead

available, peek, read, rewind, skip

Field Detail

DEFAULT_CHUNK_SIZE_4KB

public static final int DEFAULT_CHUNK_SIZE_4KB

See Also:

Constant Field Values

chunkSize

protected int chunkSize

currentBuffer

protected ByteBuffer currentBuffer

pointer

protected long pointer

currentBufferPointer

protected int currentBufferPointer

size

protected long size

Constructor Detail

RandomAccessReadBuffer

protected RandomAccessReadBuffer()

Default constructor.

RandomAccessReadBuffer

protected RandomAccessReadBuffer(int definedChunkSize)

Default constructor.

RandomAccessReadBuffer

public RandomAccessReadBuffer(byte[] input)

Create a random access buffer using the given byte array.

Parameters:

input - the byte array to be read

RandomAccessReadBuffer

public RandomAccessReadBuffer(ByteBuffer input)

Create a random access buffer using the given ByteBuffer.

Parameters:

input - the ByteBuffer to be read

RandomAccessReadBuffer

public RandomAccessReadBuffer(InputStream input)
                       throws IOException

Create a random access read buffer of the given input stream by copying the data to the memory.

Parameters:

input - the input stream to be read

Throws:

IOException - if something went wrong while copying the data

Method Detail

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

seek

public void seek(long position)
          throws IOException

Seek to a position in the data.

Specified by:

seek in interface RandomAccessRead

Parameters:

position - The position to seek to.

Throws:

IOException - If there is an error while seeking.

getPosition

public long getPosition()
                 throws IOException

Returns offset of next byte to be returned by a read method.

Specified by:

getPosition in interface RandomAccessRead

Returns:

offset of next byte which will be returned with next RandomAccessRead.read() (if no more bytes are left it returns a value >= length of source)

Throws:

IOException - If there was an error while getting the current position

read

public int read()
         throws IOException

Read a single byte of data.

Specified by:

read in interface RandomAccessRead

Returns:

The byte of data that is being read.

Throws:

IOException - If there is an error while reading the data.

read

public int read(byte[] b,
                int offset,
                int length)
         throws IOException

Read a buffer of data.

Specified by:

read in interface RandomAccessRead

Parameters:

b - The buffer to write the data to.

offset - Offset into the buffer to start writing.

length - The amount of data to attempt to read.

Returns:

The number of bytes that were actually read.

Throws:

IOException - If there was an error while reading the data.

length

public long length()
            throws IOException

The total number of bytes that are available.

Specified by:

length in interface RandomAccessRead

Returns:

The number of bytes available.

Throws:

IOException - If there is an IO error while determining the length of the data stream.

expandBuffer

protected void expandBuffer()
                     throws IOException

create a new buffer chunk and adjust all pointers and indices.

Throws:

IOException

checkClosed

protected void checkClosed()
                    throws IOException

Ensure that the RandomAccessBuffer is not closed

Throws:

IOException - If RandomAccessBuffer already closed

isClosed

public boolean isClosed()

Returns true if this source has been closed.

Specified by:

isClosed in interface RandomAccessRead

Returns:

true if the source has been closed

isEOF

public boolean isEOF()
              throws IOException

A simple test to see if we are at the end of the data.

Specified by:

isEOF in interface RandomAccessRead

Returns:

true if we are at the end of the data.

Throws:

IOException - If there is an error reading the next byte.

createView

public RandomAccessReadView createView(long startPosition,
                                       long streamLength)
                                throws IOException

Description copied from interface: RandomAccessRead

Creates a random access read view starting at the given position with the given length.

Specified by:

createView in interface RandomAccessRead

Parameters:

startPosition - start position within the underlying random access read

streamLength - stream length

Returns:

the random access read view

Throws:

IOException - if something went wrong when creating the view for the RandomAccessRead

createBufferFromStream

public static RandomAccessReadBuffer createBufferFromStream(InputStream inputStream)
                                                     throws IOException

Create e new RandomAccessReadBuffer using the given InputStream. The data is copied to the memory and the InputStream is closed.

Parameters:

inputStream - the InputStream holding the data to be copied

Returns:

the RandomAccessReadBuffer holding the data of the InputStream

Throws:

IOException - if something went wrong while copying the data

resetBuffers

protected void resetBuffers()

Reset to position 0 and remove all buffers but the first one.