GPP is a general-purpose preprocessor with customizable syntax, suitable for a wide range of preprocessing tasks. Its independence from any programming language makes it much more versatile than cpp, while its syntax is lighter and more flexible than that of m4. The syntax is fully customizable, which makes it possible to process text files, HTML, or source code equally efficiently in a variety of languages.
Barter is a tool for increasing the quality of applications written in Java. It allows the programmer to use design by contract and define other development aspects right in the classes and interfaces where they are relevant, as JavaDoc comments. It is essentially a code generator for AspectJ, implemented as an xDoclet task.
Java+ is a Java preprocessor that adds its features to any Java compiler. It has long, multi-line strings with executable inclusions like Perl or Ruby, optionally segregates Java+ strings into ResourceBundle files, eliminates the need for JSP or ASP and their implied need for Java compilers on deployment servers (a security concern), and adds absolutely no overhead in either space or time. There are graphical and command line interfaces, and a simple, general, and recursive string syntax.
The DObject Library C++ is a Java-like library that acts as a bridge between the C++ and the Java worlds. It offers a wide range of the Java facilities without losing the power of C++. It offers naming convention that is similar to the Java language, smart pointers emulating Java references, and classes emulating Java arrays.
Easy Generator Generator (EGG) is a development tool for fast and easy realization of XML to plain-text tranformations. It is similar to XSLT, Velocity, or JSP but emphasises source code generation in a model-driven generative developmen process. It comes with an iterative development process for creating templates that lets you build transformations quickly and easily.
JCPP is a complete, compliant, standalone, pure Java implementation of the C preprocessor. It is intended to be of use to people writing C-style compilers in Java using tools like sablecc, antlr, JLex, CUP, and so forth. It has been used to successfully preprocess much of the source code of the GNU C library.
The Java Exorcist is a simple Java syntax extender. By default (with no extensions), it only compiles standard Java code, but with each extension to Exorcist a new Java language construct can be defined or redefined. The Exorcist preserves line numbering at runtime and at compile-time. It can be invoked on the command line and through an ant task.