Summary	Pencil - a log-message-compiler for java.
Categories	None
License	GNU General Public License (GPL v. 2.0)
Owner(s)	nestor_kodila

Logging with Pencil and commons-logging.
Fast and safe way to log.

What is "Pencil" and how i can eat it?

"Pencil" is a log-message-compiler for java (keyword: generative programming). It takes bytecode produced by javac (or another java-compiler), transforms it and enriches it with real logging expressions.

The main goal of the "Pencil" project is to provide a mechanism to make logging easy, safe and fast. To achieve this result, "Pencil" uses its own expression language developed with the ANTLR parser-generator. But have no fear! "Pencil" is not a Language-extension. You don't need a special IDE with a new source-code viewer. There's no need to extend the syntax of java to use pencil and your code will look cleaner than it did before.
To log some stuff you simply use a class from "Pencil"-framework within your java-code. Pencil behaves kind of like a logging plugin to your code.

Example:
To compile your program without logging just compile your java-code with javac. If you want to distribute your app with logging, simply use pencil to enrich the bytecode with logging-code of your favorite logging framework. (at this moment only commons-logging is supported)

The above example is then transformed to the following code:


You can see, that the code with pencil-logging-statements is more readable than in the old-school way of logging. Pencil also provides a NullPointerException-precaution mechanism. It also does not allow to call business-logic-methods from within your logging-expressions. The result is, your code is safer than before. No more NullPointerExceptions and no more unintended business logic in the logging expressions.
Pencil simply forbids a faulty logging-functionality in your code.

Where can i download "Pencil"?

If you are interesting in pencil, you can DOWNLOAD THE ACTUAL DISTRIBUTION here.

If you have questions about pencli, please read the FAQ and the How-to within the "Documents & files"-area or send me an email.

The instalation is described here.


have fun, Andreas Siebert.