Hi Jeremias,
Many thanks for your great explanation! I'm very motivated to study
PDFDocumentGraphics2D with your explanation and your support.
I would like create the same API than iText (Paragraph, Table, etc) with FOP
(or PDFBox) and use it for our converterODF/OOXML.
I would like avoid managing layout for docx and layour for odt, but use in
the 2 cases the Paragraph, Table structures that I would like provides with
FOP or PDFBox.
I have started to manage that with PDFBox (but with FOP it will be same
thing) and I track x and y when I add a structure (to compute x/y position
and know if new page must be added) :
ex:
-----------------------------------------------------------
Document doc=new Document()
Paragrapf p = new Paragraph();
p.addRun(new Run("AAAA"));
p.addRun(new Run(" "));
p.addRun(new Run("BBBB"));
doc.addParagraph(p);
doc.save("test.pdf"); // <= here it loops to each structure and compute x, y
position, after coputing that it render each structure.
-----------------------------------------------------------
I don't know how to manage layout (x and y position) with a different means?
Anyway thank a lot for your great help.
Regards Angelo
2011/10/15 Jeremias Maerki <[email protected]>
> Hi Angelo
>
> PDFDocumentGraphics2D is a Graphics2D subclass, so the API is stable.
> The only thing special to it is the font and page size setup and the
> nextPage() method.
>
> You program once against a Graphics2D object to paint individual pages
> and that allows you to paint on the Screen (AWT/Swing), print to a
> printer (javax.print) or to create SVG (SVGGraphics2D from Apache Batik),
> PDF (PDFDocumentGraphics2D from Apache FOP), PostScript
> (PSDocumentGraphics2D from Apache XML Graphics Commons) or whatever. I
> think iText has a Graphics2D implementation, too. We could even write
> one for PDFBox.
>
> PDFBox already has the opposite direction: it takes a PDF page and can
> paint it on a Graphics2D object. That's how it does PDF2Image and how
> the PDFReader displays the PDF contents.
>
> Graphics2D is a vector graphics painting API suitable for a single
> page/box/screen. It works with absolute coordinates. You can use it to
> create paged documents. There are tools in java.awt.text that help
> laying out text but it's no full layout engine.
>
> Word processing documents (ODF/OOXML/DOC) are flow-oriented formats,
> just like HTML and XSL-FO. It's the job of a formatting engine (like
> Apache FOP) to turn that into a paged format, i.e. from not having to
> track X/Y to absolute positioning on a page. It does line breaking und
> checks how many lines fit into a page and continues on a new page if an
> overflow occurs (that's simplified).
>
> Apparently, you have a nice API in iText that allows you to build up the
> PDF by adding paragraphs and runs where you don't have to worry about
> line breaking, hyphenation and page breaks. That means, iText has at
> least a simple formatting engine built in. PDFBox doesn't have that (yet).
> FOP has a sophisticated one for XSL-FO. Apache Batik has one for the SVG
> flow-text feature (using java.text.AttributedCharacterIterator, but
> heavily relying on their internal GVT framework).
>
> The JDK has one in javax.swing.text (rendering Text, HTML and RTF, also
> using java.awt.font and java.text) although I'm starting to believe that
> it only supports line-breaking, not page breaking. That's the one I used
> in the example for PDFDocumentGraphics2D. I can't tell if that would
> make a good basis for a simple layout engine for PDFBox. But I certainly
> think it might be possible to reuse some of that and try to build a
> simple page breaker on top of that. I think that might actually one of
> the best option for have something useful relatively quickly but it
> might not fit for all possible features that ODF/OOXML offer.
>
> So, in the end I don't think you can get around to find or program some
> kind of formatter/layout engine that handles the transition from
> flow-based to absolute text, when you go from ODF/OOXML to PDF.
>
> Doing that on an engine that does not directly depend on PDFBox would
> allow you to cater for more than just PDF (taking XDocReport's and ODF
> Toolkit's view). That's why I suggested to have a look at FOP's
> intermediate format. Because if you can generate that format you have
> immediate access to all paged output formats that FOP supports (PDF, PS,
> AFP, PCL, TIFF, Print). To a lesser degree the same is also possible if
> you program against Graphics2D because you can then also produce various
> output formats (see the list of Graphics2D implementations that I gave
> above).
>
> Please note: I don't want to deny PDFBox a nice simple (flow-oriented)
> API for generating PDFs or a Graphics2D implementation. I'm just
> pointing out possible directions.
>
> And the bitter pill at the end: doing layout can be real hard. I'm
> speaking from experience.
>
> On 15.10.2011 14:09:20 Angelo zerr wrote:
> > Hi Jeremias ,
> >
> > Wow thta's a very cool sample! Thank a lot.
> >
> > With you sample I must manage x and y position that I have started with
> > PDFBox implementation.
> > It seems that PDFDocumentGraphics2D looks like PDPageContentStream (draw
> > string, set font, color, exc).
> >
> > So my question what is advantage to use PDFDocumentGraphics2D from FOP
> > instead of PDPageContentStream from PDFBox?
> > PDFDocumentGraphics2D is an API stable?
> >
> > Thank a lot for your answer.
> >
> > Regards Angelo
> >
> > 2011/10/15 Jeremias Maerki <[email protected]>
> >
> > > It turned out PDFDocumentGraphics2D was not so operational anymore.
> > > Somewhere along the way it broke. I've fixed it again [1] and added a
> > > usage example [2]. That means you'll have to download FOP Trunk [3].
> > >
> > > [1] http://svn.apache.org/viewvc?rev=1183620&view=rev
> > > [2]
> > >
> http://svn.apache.org/viewvc/xmlgraphics/fop/trunk/examples/embedding/java/embedding/ExampleJava2D2PDF.java?view=markup
> > > [3] http://xmlgraphics.apache.org/fop/download.html
> > >
> > > But guys, talking about PDFDocumentGraphics2D is getting very off-topic
> > > for this list. Please take that part to
> [email protected]
> > > from here.
> > >
> > > On 14.10.2011 23:54:56 Angelo zerr wrote:
> > > > Hi Steve
> > > >
> > > > 2011/10/14 Steve Hannah <[email protected]>
> > > >
> > > > > >
> > > > > >
> > > > > > It works but I have the same problem than PDFBox. I must manage x
> and
> > > y
> > > > > > position (increment x and y when I add some text).
> > > > > >
> > > > >
> > > > > It appears that PDFDocumentGraphics2D is just a Graphics2D context.
> > > Then
> > > > > presumably you could pass it to the paint() method of any AWT or
> Swing
> > > > > component to have that component paint itself to the PDF. E.g.
> Just
> > > use a
> > > > > JTextPane or a JTable, then pas the PDFDocumentGraphics2D object to
> > > their
> > > > > paint() methods
> > > > >
> > > >
> > > > Ok thank's for this information.
> > > >
> > > > >
> > > > >
> > > > >
> > > > > > I have started to manage that with PDFBox and it works great
> > > (increment x
> > > > > > when text is added, increment y when text is too long for the
> line,
> > > etc).
> > > > > >
> > > > > > I don't see the advantage to use PDFDocumentGraphics2D instread
> of
> > > using
> > > > > > PDFBox PDPageContentStream.
> > > > > > I'm afraid with FOP because:
> > > > > >
> > > > > > * PDFDocumentGraphics2D is not documented. It seems that nobody
> > > (google
> > > > > > tell me that) has used PDFDocumentGraphics2D to create PDF from
> > > scratch.
> > > > > >
> > > > > One google search found some API docs.
> > > > >
> > > > >
> > >
> http://www.jarvana.com/jarvana/view/org/apache/xmlgraphics/fop/1.0/fop-1.0-javadoc.jar!/org/apache/fop/svg/PDFDocumentGraphics2D.html
> > > > >
> > > > > Possibly old, but that's what 10 seconds of research found.
> > > > >
> > > >
> > > > When I said documented, I meant that I have no found documentation in
> the
> > > > FOP WebSite or other blog which explains how to use this class. I
> have
> > > not
> > > > found sample which use this class.
> > > > Your link is the Javadoc that I have already read because I have the
> > > sources
> > > > of FOP in my Eclipse Workspace.
> > > >
> > > > Regards Angelo
> > > >
> > > > >
> > > > > Best regards
> > > > >
> > > > > Steve
> > > > >
> > >
> > >
> > >
> > >
> > > Jeremias Maerki
> > >
> > >
>
>
>
>
> Jeremias Maerki
>
>
