Brad Cox (I think the same guy who invented Objective C) has released a Java preprocessor called Java+.

Java+ is an open source Java preprocessor (download) that adds these features to any Java compiler:

• Multi-line strings with executable inclusions like Perl and Ruby
• Optionally segregates Java+ strings into ResourceBundle files
• Eliminates the need for JSP or ASP and their need for Java compilers on deployment servers (a security concern)
• Optionally processes only inputs whose outputs are out of date
• Extremely fast. Astonishingly so.
• Adds no overhead, in either space or time
• Graphical and command-line interfaces
• Simple, general, recursive string syntax
• Free software, BSD open source license
• Comprehensive built-in documentation