Conceptual Architecture of MozillaFirefox (version 2.0.0.3)Jared HainesIris LaiJohn,Chun-Hung,ChiuJosh Fairhead

June 5, 2007

Introduction Discuss the conceptual architecture of Mozilla Firefox

2.0.0.3. Firefox is an open source cross-platform web browser

developed by the Mozilla Corporation The Conceptual architecture for Mozilla Firefox is based on the reference architecture of Mozilla Browser

Reference architecture of Mozilla browser includes User Interface, Browser Engine, Rendering Engine, Networking, XML Parser, JavaScript Interpreter, and Data Persistence.

Conceptual Architecture of Mozilla Firefox includes User Interface, Gecko, Necko, XML Parser, JavaScript Interpreter, and Data Persistence.

Reference Architecture of Mozilla Browser

Conceptual Architecture of Mozilla Firefox

User Interface

Gecko

Necko

JavaScript Interpreter

XPCOM XML Parser

Data Persistence

User Interface Module(1)

User Interface Module(2) in between user and Gecko

allow user inputs / requests, mainly interacts with Gecko, the rendering/browsing engine

UI components built by XUL and HTML , decorated by CSS

XPFE / XPToolkit is the development framework (based upon XUL language) that allows to build same UI components by using the same API in different platform.

AOM defines objects and relationships that compose the UI and related services . Services performs the actual application-specific tasks.

Gecko

Browser layout engine Components:

HTML Parser Style System Image Loader Content Model Frame System Graphics Interface

Gecko

Gecko

XML Parser

HTML Parser

Content Model

Necko

Image Loader

Style System

CSS Parser

Frame System

Graphics Interface

GDI

X11/GTK

Mac OS/X

JavaScript Interpreter?

Data flow within Gecko

NeckoNecko

Firefox

Network Service

Protocol Handler

Protocol Connection

File Transport Socket Transport

URL

Necko

Network Service - facilitates the construction and opening of URLs

Protocol Handler – unique protocol handler for each protocol type

Protocol Connection – any protocol-specific accessors required

File/Socket Transport – represents the physical connection

Necko

Threading application thread and a maximum number of

transport threads most protocols utilize a background thread for I/O

operations

Necko

Evolution Started as a networking library known as netlib Design goals:

Memory footprint Code maintainability Network performance

XML ParserXML Parser (Expat)

XHTML MathML SVG RDF XUL

The XML Parser is the component responsible for handling eXtensible Markup Language (XML) documents like XHTML, MathML, SVG, RDF, and XUL.

The XML Parser subsystem parses XML documents into a Document Object Model (DOM) tree.

Mozilla uses James Clark's expat parser.

XML Parser Architecture

* The arrows represent C/Java/Javascript APIs.

JavaScript Interpreter

The JavaScript Interpreter evaluates JavaScript (also known as ECMAScript) code, which may be embedded in web pages.

JavaScript is an object-oriented scripting language developed by Netscape.

JavaScript Interpreter

SpiderMonkey

XPCOM

Cross-Platform Component Object Model Manages creation, ownership, and deletion of

objects Handles message passing between objects Similar to CORBA and Microsoft COM Components:

Component, Service, and Category Managers XPConnect File/memory management, threads, data structures

XPCOM Conceptual Architecture

XPCOM

XPConnect JavaScript Interpreter

Data Persistence

Data Persistence

Session Storage

Global Storage

Gecko

Data Persistence

DOM storage Session storage

available for the page session Global storage

maintains multiple public and private storage areas used to hold data over a long period of time

References are accessed by the HTML code

Q & A

Thank you!