org.apache.fop.pdf

Class PDFObject

java.lang.Object

org.apache.fop.pdf.PDFObject

All Implemented Interfaces:

PDFWritable

Direct Known Subclasses:

PDFAction, PDFAnnotList, PDFArray, PDFCharProcs, PDFCIDFont, PDFCIDSystemInfo, PDFDestination, PDFDictionary, PDFEncryptionJCE, PDFFileSpec, PDFFunction, PDFGState, PDFICCBasedColorSpace, PDFInfo, PDFLink, PDFName, PDFNumber, PDFNumsArray, PDFOutline, PDFOutputIntent, PDFPages, PDFPathPaint, PDFResources, PDFShading, PDFText

public abstract class PDFObject
extends java.lang.Object
implements PDFWritable

generic PDF object. A PDF Document is essentially a collection of these objects. A PDF Object has a number and a generation (although the generation will always be 0 in new documents).

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.text.SimpleDateFormat	DATE_FORMAT Formatting pattern for PDF date
protected static org.apache.commons.logging.Log	log logger for all PDFObjects (and descendants)

Constructor Summary

Constructors

Constructor and Description
PDFObject() Default constructor.
PDFObject(PDFObject parent) Constructor for direct objects.

Method Summary

Methods

Modifier and Type	Method and Description
static byte[]	encode(java.lang.String text) Converts text to a byte array for writing to a PDF file.
protected void	encodeBinaryToHexString(byte[] data, java.io.OutputStream out) Encodes binary data as hexadecimal string object.
protected byte[]	encodeString(java.lang.String string) Encodes a String (3.2.3 in PDF 1.4 specs)
protected byte[]	encodeText(java.lang.String text) Encodes a Text String (3.8.1 in PDF 1.4 specs)
protected java.lang.String	formatDateTime(java.util.Date time) Formats a date/time according to the PDF specification.
protected java.lang.String	formatDateTime(java.util.Date time, java.util.TimeZone tz) Formats a date/time according to the PDF specification (D:YYYYMMDDHHmmSSOHH'mm').
protected void	formatObject(java.lang.Object obj, java.io.OutputStream out, java.io.Writer writer) Formats an object for serialization to PDF.
PDFDocument	getDocument() Returns the parent PDFDocument if assigned.
PDFDocument	getDocumentSafely() Returns the parent PDFDocument, but unlike getDocument() it throws an informative Exception if the parent document is unavailable instead of having a NullPointerException somewhere without a message.
int	getGeneration() Returns the object's generation.
java.lang.String	getObjectID() Returns the PDF representation of the Object ID.
int	getObjectNumber() Returns the object's number.
PDFObject	getParent() Returns this objects's parent.
boolean	hasObjectNumber() Indicates whether this PDFObject has already been assigned an object number.
PDFReference	makeReference() Creates and returns a reference to this object.
protected int	output(java.io.OutputStream stream) Write the PDF represention of this object
void	outputInline(java.io.OutputStream out, java.io.Writer writer) Writes a "direct object" (inline object) representation to the stream.
java.lang.String	referencePDF() Returns the PDF representation of a reference to this object.
void	setDocument(PDFDocument doc) Sets the parent PDFDocument.
void	setObjectNumber(int objnum) Sets the object number
void	setParent(PDFObject parent) Sets the direct parent object.
protected byte[]	toPDF() Encodes the object as a byte array for output to a PDF file.
protected java.lang.String	toPDFString() This method returns a String representation of the PDF object.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static org.apache.commons.logging.Log log

logger for all PDFObjects (and descendants)

DATE_FORMAT

protected static final java.text.SimpleDateFormat DATE_FORMAT

Formatting pattern for PDF date

Constructor Detail

PDFObject

public PDFObject()

Default constructor.

PDFObject

public PDFObject(PDFObject parent)

Constructor for direct objects.

Parameters:

parent - the containing PDFObject instance

Method Detail

getObjectNumber

public int getObjectNumber()

Returns the object's number.

Returns:

the PDF Object number

hasObjectNumber

public boolean hasObjectNumber()

Indicates whether this PDFObject has already been assigned an object number.

Returns:

True if it has an object number

setObjectNumber

public void setObjectNumber(int objnum)

Sets the object number

Parameters:

objnum - the object number

getGeneration

public int getGeneration()

Returns the object's generation.

Returns:

the PDF Object generation

getDocument

public final PDFDocument getDocument()

Returns the parent PDFDocument if assigned.

Returns:

the parent PDFDocument (May be null if the parent PDFDocument has not been assigned)

getDocumentSafely

public final PDFDocument getDocumentSafely()

Returns the parent PDFDocument, but unlike getDocument() it throws an informative Exception if the parent document is unavailable instead of having a NullPointerException somewhere without a message.

Returns:

the parent PDFDocument

setDocument

public void setDocument(PDFDocument doc)

Sets the parent PDFDocument.

Parameters:

doc - the PDFDocument.

getParent

public PDFObject getParent()

Returns this objects's parent. The parent is null if it is a "direct object".

Returns:

the parent or null if there's no parent (or it hasn't been set)

setParent

public void setParent(PDFObject parent)

Sets the direct parent object.

Parameters:

parent - the direct parent

getObjectID

public java.lang.String getObjectID()

Returns the PDF representation of the Object ID.

Returns:

the Object ID

referencePDF

public java.lang.String referencePDF()

Returns the PDF representation of a reference to this object.

Returns:

the reference string

makeReference

public PDFReference makeReference()

Creates and returns a reference to this object.

Returns:

the object reference

output

protected int output(java.io.OutputStream stream)
              throws java.io.IOException

Write the PDF represention of this object

Parameters:

stream - the stream to write the PDF to

Returns:

the number of bytes written

Throws:

java.io.IOException - if there is an error writing to the stream

outputInline

public void outputInline(java.io.OutputStream out,
                java.io.Writer writer)
                  throws java.io.IOException

Writes a "direct object" (inline object) representation to the stream. A Writer is given for optimized encoding of text content. Since the Writer is buffered, make sure flush() is called before any direct calls to out are made.

Specified by:

outputInline in interface PDFWritable

Parameters:

out - the OutputStream (for binary content)

writer - the Writer (for text content, wraps the above OutputStream)

Throws:

java.io.IOException - if an I/O error occurs

toPDF

protected byte[] toPDF()

Encodes the object as a byte array for output to a PDF file.

Returns:

PDF string

toPDFString

protected java.lang.String toPDFString()

This method returns a String representation of the PDF object. The result is normally converted/encoded to a byte array by toPDF(). Only use this method to implement the serialization if the object can be fully represented as text. If the PDF representation of the object contains binary content use toPDF() or output(OutputStream) instead. This applies to any object potentially containing a string object because string object are encrypted and therefore need to be binary.

Returns:

String the String representation

encode

public static final byte[] encode(java.lang.String text)

Converts text to a byte array for writing to a PDF file.

Parameters:

text - text to convert/encode

Returns:

byte[] the resulting byte array

encodeText

protected byte[] encodeText(java.lang.String text)

Encodes a Text String (3.8.1 in PDF 1.4 specs)

Parameters:

text - the text to encode

Returns:

byte[] the encoded text

encodeString

protected byte[] encodeString(java.lang.String string)

Encodes a String (3.2.3 in PDF 1.4 specs)

Parameters:

string - the string to encode

Returns:

byte[] the encoded string

encodeBinaryToHexString

protected void encodeBinaryToHexString(byte[] data,
                           java.io.OutputStream out)
                                throws java.io.IOException

Encodes binary data as hexadecimal string object.

Parameters:

data - the binary data

out - the OutputStream to write the encoded object to

Throws:

java.io.IOException - if an I/O error occurs

formatObject

protected void formatObject(java.lang.Object obj,
                java.io.OutputStream out,
                java.io.Writer writer)
                     throws java.io.IOException

Formats an object for serialization to PDF.

Parameters:

obj - the object

out - the OutputStream to write to

writer - a Writer for text content (will always be a wrapper around the above OutputStream. Make sure flush is called when mixing calls)

Throws:

java.io.IOException - If an I/O error occurs

formatDateTime

protected java.lang.String formatDateTime(java.util.Date time,
                              java.util.TimeZone tz)

Formats a date/time according to the PDF specification (D:YYYYMMDDHHmmSSOHH'mm').

Parameters:

time - date/time value to format

tz - the time zone

Returns:

the requested String representation

formatDateTime

protected java.lang.String formatDateTime(java.util.Date time)

Formats a date/time according to the PDF specification. (D:YYYYMMDDHHmmSSOHH'mm').

Parameters:

time - date/time value to format

Returns:

the requested String representation