Before building your application, your application components must be assembled into projects. Projects and their usage are described in Applications and Projects. Review the information in Managing Project Dependencies to understand project dependencies and making JARs and J2EE libraries available to your projects.
Under normal circumstances, you will never explicitly build your projects/applications since by default, Workshop builds your files automatically, using the Eclipse Build Automatically feature. This feature does an incremental build whenever a program file is saved.
If you wish, you can build your files, projects and enterprise applications manually. Workshop uses the standard Eclipse commands for building, as described in detail in the Eclipse/JDT documentation, available by clicking Help > Contents and choosing Java Development User Guide from the Contents pane at the left.
The clean operation (the Project > Clean command) cleans all build artifacts resulting from a previous build of a project. It's a good way to "start over" so that you know that your build output includes only the most up-to-date files based on your source code. You should clean your project before final production deployment.
Before you deploy your application to a production environment, you will probably want to perform a clean operation followed by a complete build in a controlled environment. In this way you can ensure that you have a formal, repeatable build process that you use every time you deploy an application to production.
The Project menu provides the following standard Eclipse commands for building your files: