General Info about FISSURES


The goal of the FISSURES Project is to provide a framework for seismology software and data transmission based on CORBA and the Java Platform that are developed in an open and cooperative fashion and released under the terms of the Gnu Public License.


What is the minimum needed to use FISSURES?

The absolute minimum that is needed is the core IDL. The IDL defines the FISSURES objects and interfaces and can be used to create FISSURES friendly servers and clients in any CORBA supported language. In order to do this you will need to find an ORB and an IDL compiler for the language you are interested in. The IDL compiler will create source code for all the objects and interfaces in that language. A stand alone application might be able just use this code, perhaps with some additional libraries, but a distributed client or server will need to make use of the ORB.

Do I have to compile the IDL myself?

If you are using Java, no, but for any other language, yes. While you can compile the IDL into Java yourself, it is rather time consuming. Usually it is much easier to download the Java source precompiled from the IDL. You can either get the actual Java code, or a jar with all of the Java compiled as well. See the FISSURES IDL project for download links as well as documentation on its use.

What else might I find interesting if I am using Java?

Because FISSURES development has almost exclusively been done in Java so far, there is much more available to base new programs on than for other languages. The FISSURES Impl subproject is a collection of code that is not an application, but a library of useful code that directly complements the IDL generated code. Java programmers should definitely use this as it provides needed implementations of the assorted valuetype objects. It may be of interest as a reference for other langages as well. The Fissures Util project is forms support code that is less tightly coupled to the IDL, but still provides useful functionality, such as GUI widgets and caching proxies for various servers.

Where can I go for more information about CORBA?

There are many good sources of information about CORBA on the web. Just a few are given here:

The OMG, developer of CORBA.

OOC, developer of Orbacus, a C++ and Java ORB, with a very nice free-for-noncommercial license. This is the ORB and IDL compiler used in developing FISSURES.
Note: OOC was recently bought out by Iona, and their once very generous license is now much more restrictive, to the point of it being unusable by most researchers.

Two open source Java ORBs are JacORB and OpenORB. We are investigating both of these as replacements for Orbacus.

Javasoft at Sun, the source for Java. The new version of Java, 1.4, supposedly has much better support for CORBA and may be all you need.

Getting Involved

We do not currently have a very formal system for being involved in FISSURES or for submiting suggestions or code. Basically, if you are interested, you should subscribe to the mailing list, and post your suggestions there.

To subscribe to the mailing list, send an email to the mailing list with

subscribe fissures-dev

in the body.

Please remember that if you send an email to fissures-dev, it goes to everyone on the list. If you are trying to subscribe or unsubscribe you should send the email to the mailing list instead.

If you have a project that you are working on that is FISSURES-friendly and would like to let others know about it, send the webmaster an email and I will add it to the list of related projects.

Reference Library

Getting up to speed with FISSURES is currently more difficult than it should be, largely due to the fact that the code has outpaced the documentation. In addition, the design was large, and done by a very small group of people, so the detailed knowledge of the system is in only a few heads.

The place to understand FISSURES objects at their most fundamental level is the IDL itself. Of course, understanding the syntax and how it is mapped into a given programming language is needed as well.

Another useful place is the javadocs that are generated both directly from the IDL and from the java source code compiled from the IDL. Some of the difficulties in syntax of IDL are removed by looking at the java derived version, but have the added complexity of the additional helper classes generated for each IDL entity. A useful overview of the way Fissures servers are located can be found here.

Looking at existing client and server applications is also very useful. Our simple clients can be useful as a starting point.

Bug Reporting

If you find bugs or would like to submit a request for enhancement, you should post them to the fissures-dev email list. General discussions should also take place via the the fissures-dev mailing list . For information on how to subscribe to the fissures-dev email list, see the “Getting Involved” paragraph above.