DS520 - Lecture Outline

DePaul University - Winter 2003 - Kenniston

Since the content of this course has changed significantly since the last time I taught it, the outline below is approximate and is subject to revision as the term progresses. More detail will be added as we go, so that this outline will serve as a summary of all the topics we have covered, and can thus be used as a study guide for the exams. This outline will also supply the links to the online readings.

Week 1 - 2003-01-09 Thursday - Intro to CORBA

• Administrative stuff:
  • Instructor background.
  • Prerequisites.
  • Use of dlweb.
  • Homework policy. (50% of course grade).
  • Office hours.
• Midterm exam: open book and note. (15% of course grade)
• Final project: (35% of course grade)
  • Your choice of topic, but you must get approval from instructor.
  • Write a paper.
  • Present the material to the class - aprox. 10-15 minute talk.
  • DL students contact instructor for special arrangements.
• Overall course organization:
  • We will look at various distributed systems frameworks (DSFs).
  • You will write some programs using DSFs.
  • Instructor is also learning, and will be more of a guide/mentor than a guru with all the answers.
• Terminology:
  • Patterns.
  • Class libraries.
  • Frameworks.
  • Components.
  • Objects.
• Why use frameworks: Re-use
  • Reduce cost.
  • Increase reliability.
  • Reduce time-to-market.
• Distributed Systems are especially hard to design and implement correctly.
• Advantages of IP, TCP, sockets, RPC:
  • Independent of CPU hardware.
  • Independent of network hardware.
  • Independent of operating system.
  • Independent of programming language.
  • Independent of vendor.
• CORBA - an example of a DSF.
• CORBA provides the same advantages, but at a higher level (distributed objects).
• CORBA objects (implemented with programming language objects).
• IDL (Interface Definition Language).
• ORB (Object Request Broker).
• IIOP (protocol for communicating ORBs).
• Proxies: stubs and skeletons.
• Marshalling.
• IOR (to move object references across the network).
• callbacks.
• Language bindings.
• CORBA services.
• CORBA facilities.
• The OMG.
• Comparison with COM/DCOM/.NET.

Week 2 - 2003-01-16 Thursday - Implementing CORBA Objects in Java

• IDL files
• idlj -fall -oldImplBase
• tnameserv
• Client code
• Initializing the ORB
• Name services
• Server code
• Registering the object
• Demo on one machine, then across network (-ORBInitialHost nameserverhost)
• Primitive types in detail
  • boolean
  • char/wchar
  • string/wstring
  • octet, short, long, long long
  • float, double
• Holder types for out and inout arguments.
• Struct, enum, array, const
• Attributes and accessors.

Class examples:

• Calculator
• args

Readings:

• An IDL Tutorial from Sun.
• Some more documentation on IDL and Java from Sun. The "Hello World Tutorial" is particularly helpful.
• The mapping between IDL and CORBA types is shown in this table.
• If you prefer PowerPoint-style bullet lists, try this CORBA and Java Tutorial.

Week 3 - 2003-01-23 Thursday - More CORBA

• Exception handling across the network with CORBA.
• Interoperable Object References (IORs), stringification
• Automatic marshalling and stub creation during the call of a callback.
• Review of Java objects and references, CORBA objects and references, Java and CORBA interfaces, and how they relate to callbacks and polymorphism.
• Iterators in CORBA.
• Naming Services and Naming Contexts.
• DII (Dynamic Invokation Interface) and DSI (Dynamic Skeleton Interface), and their use in diagnostic tools (e.g. debuggers) and gateways.
• Using delegation (aka "tie" method) to work around the lack of multiple implementation inheritance in Java.
• Options for server threading.
• Open-source ORBS.
• CORBA with C++: typedefs, memory management.

Class Examples:

• The same args example from last week includes exceptions and callbacks.
• The Naming Service example shows both Naming Contexts and Iterators.
• The C++ example shows what CORBA looks like in a C++ program.

Week 4 - 2003-01-30 Thursday

Readings:

• For just about anything related to Web standards, check out the W3C web site.
• Microsoft's Introduction to Web Services.
• More intro to .NET from MS is here and here.
• Here is another view of what .NET is all about.
• A number of good short tutorials related to Web Services are here. Unfortunately the online book doesn't work. :-)
• Some .NET tutorials W3Schools.
• To download the whole Internet, click here :-)
• The last page of the Internet.

Week 5 - 2003-02-06 Thursday - Midterm Exam

The midterm will be held in the usual room at the usual class meeting time.

The midterm may include any material covered in lectures 1 through 4, or in homeworks due on or before the date of exam. It will not include obscure things from the readings which have not been mentioned in class.

The exam will be open-book and open-note, but not open-laptop or open-neighbor. The midterm exam counts for ??% of the course grade.

Week 6 - 2003-02-13 Thursday

Week 7 - 2003-02-20 Thursday

Week 8 - 2003-02-27 Thursday

Week 9 - 2003-03-06 Thursday

Week 10 - 2003-03-13 Thursday

Week 11 - 2003-03-20 Thursday - Final Exam

The final exam for this course will be on Thursday, March 20, 2003, in the usual classroom (CS&T 222), at the usual class meeting time (5:45-9:00 PM).

The final exam will consist of everyone's project presentation. Each of you will have 9 minutes (including questions) to present your work, so that we can get through everyone in a single 3-hour session. Your written project is also due at this time.