Architecture

The following documents give a high-level discussion of some aspects of the ORB architecture:

• PEPt architecture. This is the request handling architecture for the ORB.
• Server Activation Framework document.This discusses the current ORBD design and some ideas for a portable implementation using the Object Reference Template that would replace the current ORBD. This document is only available in PDF, due to HTML conversion problems in FrameMaker 7.
• ORBD Architecture. This is an early document on some aspects of fault tolerance and load balancing

Here are some more detailed descriptions of parts of the ORB design:

• Presentation
  • Dynamic RMI-IIOP
    • Optimization notes. These changes are now in place.
    • Design
• Encoding. This area is not well documented at present. Everett Anderson (no longer involved with this project) wrote some useful documentation back in 2002:
  • Serialization 1: Overview
  • Serialization 2: Valuetype Code
  • Serialization 3: RMI-IIOP Stream Format 2 Overview
  • Serialization 4: Serializable Refresh
  • Serialization 5: Stream Format 2
  • Serialization 6: Remaining Items
  Some parts of these presentations are a bit outdated, but the technical content is still correct and useful.
• Protocol

  There's not a lot written for this layer either. There is a lot of code in the ORB that represents the GIOP protocol messages, but that is pretty simple. The transport-protocol dispatch does need to be documented somewhere.

  • GIOP Testing
  • GIOP Blunders (aka things I wish the GIOP specification did differently)
• Transport
• Utility (or things that do not fit elsewhere)
  • Thread Pool
  • Monitoring Extensions
  • Copyobject

The ORB also has an extensive internal SPI that is used by the GlassFIsh project. Javadocs for the ORB SPI are available here.