New Acceleo project

The aim of an Acceleo project is to generate text from a model. For this tutorial, we will create a new Acceleo module for generating java beans from a UML model.

To create a new Acceleo project, you can right click on the package explorer view then New->Acceleo Project.

Choose a correct plugin name for the project, then click next.

Next you can create a new Acceleo module file.

• Select the folder in which you want to create the new module file.
• Fill in the module name
• Optionally, you can browse for an existing file which will be copied into the new module file. This could be useful to create a module from an existing file.
• Then, select the metamodel from which your generation file will take its types (in this example, UML)
• Finally, choose the metaclass that will be used to generate the file (in this example, Class)

You can create more than one module file in this project by using the "Add" button ont the left.

Clicking on finish will create the module file(s), and some files automatically generated from it ( more on these below ).

The Acceleo editor

The module editor provides the following features :

• Syntax highlighting
• Content assistant (ctrl + space)
• Error detection
• Quick fixes (ctrl + shift + 1)
• Dynamic outline
• Quick outline (ctrl + O)
• Code folding
• Open declaration (either with 'ctrl + left click' or 'F3')
• Search references (ctrl + shift + G)

For more information about the Acceleo syntax, please read the official OMG specification accessible from : <http://www.omg.org/spec/MOFM2T/1.0/>

Creating a module to generate java beans

We would like to create a bean for each of the classes defined in the model. Here is the code for the module file :

[module generate('http://www.eclipse.org/uml2/2.1.0/UML')/]

[template public generate(c : Class)]
        [file (c.name.concat('.java'), false)]
        public class [c.name.toUpperFirst()/] {
        [for (p : Property | c.attribute)]
        private [p.type.name/] [p.name/];
        [/for]
        [for (p : Property | c.attribute)]
        public [p.type.name/] get[p.name.toUpperFirst()/]() {
                return this.[p.name/];
        }
        [/for]
        [for (o : Operation | c.ownedOperation)]
        public [o.type.name/] [o.name/]() {
                // TODO should be implemented
        }
        [/for]
        }
        [/file]
[/template]

As shown below, the content assistant provides choices for the UML metamodel :

The resulting java file generated by launching this module file will look like this :

The java file

Note : This feature may evolve in future releases.

Next to each module file containing a [comment @main] annotation, a java file with the same name is automatically generated. This allows you to launch the generation via the doGenerate() method. This can be achieved either by creating a new instance of the class, or calling its main() method.

The ant task

Note : This feature may evolve in future releases.

If you create a tasks folder at the root of our project, there will also be generated an ant file which can be used to launch a generation with the specified template. In order to use this build file, copy it inside the project containing the model to generate from, rename it to build.xml for example, then change the MODEL and TARGET properties accordingly. Launch the build via External Tools > Run As > Ant Build.