com.etymon.pjx
Class PdfInputFile

java.lang.Object
  com.etymon.pjx.PdfInputFile

All Implemented Interfaces:

PdfInput

public class PdfInputFile
extends java.lang.Object
implements PdfInput

Provides low-level methods for reading portions of a PDF document. PdfReader accesses PDF documents through the PdfInput interface, which is implemented by this class. The portions of the document are read from the file system as they are requested, which reduces memory consumption as compared to PdfInputBuffer but is a bit slower.

This class is synchronized; however, note that since it acts as a wrapper around a file that is kept open, it is the calling method's responsibility to ensure that the file is not modified externally to this class. If that is a problem, use PdfInputBuffer.PdfInputBuffer(File), which reads the entire file into memory and closes it immediately.

Field Summary

protected java.nio.channels.FileChannel	_fileChannel The file channel associated with the PDF document.
protected long	_length The length of the input file.
protected java.lang.String	_name The input file name.
protected java.io.RandomAccessFile	_randomAccessFile The random access file containing the PDF document.

Constructor Summary

PdfInputFile(java.io.File pdfFile)
Constructs a PDF input source based on a specified file.

Method Summary

void	close() Closes the PDF document and releases any system resources associated with it.
long	getLength() Returns the length of the PDF document.
java.lang.String	getName() Returns a name string associated of the PDF document.
java.nio.ByteBuffer	readBytes(long start, long end) Returns a specified portion of a PDF document as a ByteBuffer.
java.nio.CharBuffer	readChars(long start, long end) Returns a specified portion of a PDF document as a CharBuffer.

Methods inherited from class java.lang.Object

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

Field Detail

_fileChannel

protected java.nio.channels.FileChannel _fileChannel

The file channel associated with the PDF document.

_length

protected long _length

The length of the input file.

_name

protected java.lang.String _name

The input file name.

_randomAccessFile

protected java.io.RandomAccessFile _randomAccessFile

The random access file containing the PDF document.

Constructor Detail

PdfInputFile

public PdfInputFile(java.io.File pdfFile)
             throws java.io.IOException

Constructs a PDF input source based on a specified file. The file is kept open, and portions of it are read as they are requested. It is the calling method's responsibility to ensure that the file is not modified externally to this class.

Parameters:

pdfFile - the source file.

Throws:

java.io.IOException

Method Detail

close

public void close()
           throws java.io.IOException

Closes the PDF document and releases any system resources associated with it.

Throws:

java.io.IOException

getLength

public long getLength()

Description copied from interface: PdfInput

Returns the length of the PDF document.

Specified by:

getLength in interface PdfInput

Returns:

the length (in bytes) of the PDF document.

readBytes

public java.nio.ByteBuffer readBytes(long start,
                                     long end)
                              throws java.io.IOException

Description copied from interface: PdfInput

Returns a specified portion of a PDF document as a ByteBuffer.

Specified by:

readBytes in interface PdfInput

Parameters:

start - the offset position of the first byte to read.

end - the offset position at which to stop reading. (The byte at this offset is not included.)

Returns:

the requested portion of the PDF document.

Throws:

java.io.IOException

readChars

public java.nio.CharBuffer readChars(long start,
                                     long end)
                              throws java.io.IOException

Description copied from interface: PdfInput

Returns a specified portion of a PDF document as a CharBuffer.

Specified by:

readChars in interface PdfInput

Parameters:

start - the offset position of the first byte to read.

end - the offset position at which to stop reading. (The byte at this offset is not included.)

Returns:

the requested portion of the PDF document.

Throws:

java.io.IOException

getName

public java.lang.String getName()

Description copied from interface: PdfInput

Returns a name string associated of the PDF document.

Specified by:

getName in interface PdfInput

Returns:

the name of the PDF document.