Book Review: Jython Essentials
By Samuele Pedroni & Noel Rappin, published by O'Reilly 2002
Jython Essentials, at 275 pages, is a fairly slender volume considering the ground it covers.
The first half of Jython Essentials (chapters 1-5) describes the Python language, covering basics such as lists, tuples, string slicing, and mapping functions, but also explaining how Jython compares with standard Python in the language details described. For example, Python is a language that allows multiple inheritance, but Java allows a class to inherit from only one parent class. So how does the Jython hybrid marry these two approaches? (You'll find the answer on page 96.)
The second half of Jython Essentials (chapters 6-13) focuses on how to access and use effectively the Java libraries that are now accessible to Python. It discusses the importance of the JavaBean component model, and how it helps the Jython programmer to write succinct code. It demonstrates rapid application development using Java Swing, shows how you can access a database using JDBC, write servlets, and perform unit testing all within the framework of Jython.
If you're reading this and wondering whether or not it's worth buying the book to help you investigate the Jython language - it IS! Jython Essentials is a great book to get you started. If you are a 'dabbler', this book might be all you need. If you are serious about using Jython to build an application, then you will probably need to supplement this book with a thicker volume on Jython and/or Python. But read this book to decide whether you like Jython.
In summary, Jython Essentials provides the perfect introduction to Python and Jython for the Java programmer. I doubt it does the same for a Python programmer who does not know Java, but, hey, there's probably not many of those around who want to learn Jython (my apologies if you're one of them!).
SW, April 2003.