Java IDE for Children and Beginning Programmers
Java Other


Java IDE for Children and Beginning Programmers

JUDO website

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After running JUDO, go to the Help menu and select Tutorials. There are several topics to read through and learn to get you started writing your own programs.

General help with installing or running JUDO
Help writing programs


JUDO is available in English, French, Indonesian, Italian, Slovenian, and Spanish. If using the Windows installer, language can be selected during installation. For other operating systems: after unpacking, the language can be selected in



JUDO is a program written to help people learn to program, pure and simple. It is free software and you are encouraged to give it to others, look at its source code, or improve it.

JUDO was developed on the Windows platform, but some care was taken to make it cross-platform. However, I have not tested it, or even installed it all platforms.

I created JUDO while I was teaching a programming class to 12-14 year olds in Boston, MA. The program I did this with is called Citizen Schools ( and I recommend that you check it out. You may find similar opportunities in your community!

Your installation of JUDO may include a copy of the Java Development Kit from Sun Microsystems, Inc. It is governed by Sun Microsystems, Inc. Binary Code License Agreement.

What a JUDO program looks like:

void main()

    printLine("What is your name?");
    String name = readString();

    printLine("Hi " + name + ". Type in a color.");
    Color c = readColor();

    fillCircle(100, 30, 100);

    printLine("Now go paint a face!");

    while(true) {
        if (getMouseEvent()) {
            setColor( randomColor() );

            if (getMouseButton(1)) {
                fillCircle(getMouseX()-5, getMouseY()-5, 10);

JUDO program code and running program

JUDO function reference

Contributing to JUDO

Developers, if you want to help the children of the world learn to program, consider contributing to JUDO. Here are some areas that could use attention:

  • Update to latest Java version
  • Testing and bug fixes on Macos X and Linux
  • Installers or executable JARs for MacOS X and Linux
  • Double-buffering with methods such as enableBuffering() and drawBuffer()
  • Right-side, hideable JUDO Function reference UI, perhaps accordion style (in groups of functions: Graphics, I/O, Mouse, Keyboard, etc)
  • Help on documentation

The majority of JUDO development happened way back in 2001. I've come a long way since then :) JUDO could use some major refactoring or even a rewrite... alpha