Tomato

The prototype works sufficiently to be used to help develop parts of itself. As parts of Tomato are developed in Tomato, the development process itself is being evaluated to find ways to improve Tomato. Thus, Tomato development is shaped by real-world development requirements, rather than adherence to a predetermined abstract design. This process of long-term ad-hoc prototyping1 should either produce a working visual programming system, or leave a trail of empirical evidence to indicate why general purpose visual programming systems aren't viable.

Once the Tomato prototype can handle most development tasks and demonstrate that general purpose visual programming is viable, it will be redesigned from scratch. The next generation Tomato will be developed entirely within the final evolution of the Tomato prototype.

To our knowledge, Tomato is the first open source development tool of its kind for the Java platform.

Why?

Specialised visual programming languages -- eg., National Instruments' LabVIEW, the shader language in Houdini, or ToonTalk -- have proven successful in niche markets or genres. In these contexts, visual programming has demonstrated advantages over traditional text-based programming.

Visual programming has not yet made a significant impact on general application development. While efforts like Sun's BeanBox or the BlueJ project are promising, they are limited in scope. Tomato was created to explore the use of visual programming for general purpose development.

• A visual programming language -- based on an "icons on strings" metaphor -- for creating, testing, and compiling scripts and new Java classes. Java classes may be instantiated and manipulated at design-time, which facilitates early testing, debugging, and productive experimentation. Program execution is displayed with dynamic visualisation -- colour changes are used to indicate method invocation, variable assignments, etc., and these occur in real time. The discrete stages of designing, writing, testing, debugging, and compiling code are merged into a unified software modeling process.

  The visual language supports dynamic execution of source code during development. Programs can be assembled from small, individually-tested units. Each unit can be assembled from even smaller units, and so on. All units can be run and tested during construction. Some units may even continue to execute while they are assembled into a whole.2 This may represent a uniquely powerful "run early, run always" development methodology.

• An integrated development environment to manage visual source code and generate Java applications. This is of a relatively conventional design.

• A collection of useful reuseable Java classes with Java source code, including database-enabled derivations of the standard JFC/Swing widgets. (These are being developed as a separate project at http://dbappbuilder.sourceforge.net) These may be used within Tomato or any other Java development environment.

Goals

• Reduce application development time.
• Reduce developer effort.
• Reduce the opportunity for syntax and logic errors.
• Integrate prototyping, development, productive experimentation, and testing into the development process from the earliest stages.
• Automate and/or encourage best practices.
• Encourage the development of reuseable classes.
• Encourage use of reusable design patterns.
• Facilitate implementation and use of code generators.

Limitations

The visual scripting and class authoring facilities are incomplete. It is possible to write useful Java classes, but inner classes are not yet supported, building expressions is laborious, parameters cannot be defined for new methods and constructors, and so on.

The documentation, including this document, is incomplete.

These and other limitations will be addressed in future versions.

In other words, this tomato ain't ripe! Tomato is being released at this embryonic stage in order to develop interest and solicit feedback on the design.

Requirements

You will require a version 1.4.x Java 2 Platform and should have a Java compiler.

See the Download and Installation section below for URLs where you can obtain these.

The Java compiler is optional, but without it you cannot compile new classes; you will only be able to work with existing Java classes.

License

Tomato may not be used to test or develop applications where vertebrate lifeforms may be harmed by a possible malfunction. This includes but is not limited to medical, weapons, and aircraft flight control systems.

The Tomato source code is released under the Gnu Public License, a copy of which can be found at http://www.gnu.org.

Classes and applications created using Tomato are not bound by this license.

"Java" is a trademark of Sun Microsystems, Inc.

"Linux" is a trademark of Linus Torvalds.

"Windows" is a trademark of Microsoft Corporation.

Wiki

Forums

SourceForge.net

FAQ

None yet...

Current Version

1. Download and install the Sun Java 2 Standard Edition SDK from http://java.sun.com/j2se/1.4.1/download.html. Obtain the SDK, not the JRE. The JRE (Java Runtime Edition) does not include the Java compiler.

2. (Optional) The Sun Java compiler is slow. You may wish to use the Jikes compiler, which is much faster. Obtain it from http://www-124.ibm.com/developerworks/oss/jikes/. Jikes is just the compiler -- you'll still need the Java 2 Platform.

3. Download Tomato.zip to a directory of your choice.

   Download: http://sourceforge.net/project/showfiles.php?group_id=67296

4. Unzip the Tomato.zip file, including all its subdirectories, into a directory of your choice.

Running Tomato

Note: In the following instructions, replace <directory> with the directory you created in Step 4 under Download and Installation.

Windows: Select "Start | Run", enter java <directory>/Tomato

UNIX or Linux: Type cd <directory>; java Tomato

MacOS: Unknown.

Getting Started

Bugs

The most annoying bug is that your visual programming source files -- 'Models' in the Tomato parlance -- may occasionally become corrupt when saved. Make frequent backups!

Compilation using Jikes does not work under Windows.

Some of the sample models may not work reliably under Windows.

Contact

Author

Footnotes

1 I.e., "hacking" in the classic sense.

2 Modifying an application while it executes is an unusual and strangely exhilarating experience.

3 Botanically, a tomato is a fruit.