vmote 2003/04/06 21:43:41
Modified:src/documentation/content/xdocs/design book.xml
src/documentation/content/xdocs/dev book.xml
Added: src/documentation/content/xdocs/dev implement.xml
Removed: src/documentation/content/xdocs/design architecture.xml
Log:
Move design/architecture.xml to dev/implement.xml.
Revision ChangesPath
1.7 +0 -3 xml-fop/src/documentation/content/xdocs/design/book.xml
Index: book.xml
===
RCS file: /home/cvs/xml-fop/src/documentation/content/xdocs/design/book.xml,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -r1.6 -r1.7
--- book.xml 24 Mar 2003 21:37:20 - 1.6
+++ book.xml 7 Apr 2003 04:43:41 - 1.7
@@ -14,9 +14,6 @@
-
-
-
1.14 +1 -0 xml-fop/src/documentation/content/xdocs/dev/book.xml
Index: book.xml
===
RCS file: /home/cvs/xml-fop/src/documentation/content/xdocs/dev/book.xml,v
retrieving revision 1.13
retrieving revision 1.14
diff -u -r1.13 -r1.14
--- book.xml 7 Apr 2003 04:22:59 - 1.13
+++ book.xml 7 Apr 2003 04:43:41 - 1.14
@@ -11,6 +11,7 @@
+
1.1 xml-fop/src/documentation/content/xdocs/dev/implement.xml
Index: implement.xml
===
http://cvs.apache.org/viewcvs.cgi/*checkout*/xml-forrest/src/resources/schema/dtd/document-v11.dtd";>
Implementation Overview
Following a Document Through FOP
The purpose of this document is to tie together the FOP design (interface)
with some of the key points where control is passed within FOP (implementation), so
that developers can quickly find the section of code that is relevant to their needs.
The process described is for a "typical" command-line document. All classes are in
org.apache.fop unless otherwise designated.
Overview
The input FO document is sent to the FO tree builder via SAX events.
Fragments of an FO Tree are built from this process. As each page-sequence element is
completed, it is passed to a layout processor, which in turn converts it into an Area
Tree. The Area Tree is then given to the Renderer, which converts it into a stream of
data containing the output document. The sections below will provide additional
details. Where needed differences between the trunk and maintenance branches are shown
in tabular format.
Startup
The job starts in apps.Fop.main().
Control is passed to apps.CommandLineStarter.run().
Control is passed to apps.Driver.render(). This class fires up
a SAX parser, the events from which indirectly control the remaining processing,
including building the FO Tree, building the Area Tree, rendering, output and
logging.
Formatting Object Tree
TrunkMaintenance
The SAX events that the parser creates are handled by
fo.FOTreeBuilder, which uses startElement(),
endElement(), and characters() methods to build the FO
Tree.
fo.FOTreeBuilder.endElement() runs the end() method for each
node as it is created. The fo.pagination.PageSequence class overrides this
end() method to run apps.LayoutHandler.endPageSequence(), which in turn runs
fo.pagination.PageSequence.format().
the end of a PageSequence element causes the PageSequence object to be
passed to apps.StreamRenderer.render, which in turn runs
fo.pagination.PageSequence.format.
fo.pagination.PageSequence.addFlow() programatically adds a
Flow object to the page sequence.
fo.pagination.PageSequence.makePage() creates a BodyArea and passes it
to fo.Flow.layout
the layout process is then driven from
fo.pagination.PageSequence.format.
Layout
There are layout managers for each type of layout decision.
They take an FO Tree as input and build a laid-out Area Tree from it.
The layout process involves finding out where line breaks and page breaks should be
made, then creating the areas on the page.
Static areas can then be added for any static regions.
As pages are completed, they are added to the Area Tree.
Area Tree
The area tree is a data structure designed to hold the page areas.
These pages are then filled with the page regions and various areas.
The area tree is used primarily as a minimal structure that can be rendered
by the rendere
