Java Program is a free software utility that provides you with the source code for several popular Java-based widgets. This gives you the ability to see how these apps function, and you can even play with them to see if you can add any functionality of your own. The software includes source code for several exceptionally basic apps, like a calculator, Armstrong number, sum of series, bank management, pattern series, number and palindrome strings, and much more.

The user interface for this software is straightforward and exceptionally basic. It works a lot like any other library of content. You can select programs from a list that populates the main area of the app, and when you click on one of the programs, it takes you to a page containing the source code. The code is formatted appropriately for easy reading, and you can save pieces of the code to be used in other locations.

If you want to learn how to code in Java, this is one of the best ways to learn. Reverse engineering existing apps is an excellent learning method for developing your own apps. The only true way to know how something works is to take it apart.