Java Code Generation from Class Diagram

VP-UML supports generating Java source code from UML class model, and keeping the code and model synchronized. In this tutorial we will develop a simple class diagram, generate code from it, modify the code and update the changes back to UML class model.

Start VP-UML in a new workspace.
Create a class diagram and name it as Employee. You can create a class diagram through the Diagram Navigator.
Select Class from diagram toolbar and click on class diagram to create a class. Name it as Person.
Create attributes in it. Right click on Person and select Add Attribute from the popup menu. Enter name : String to name the attribute as name and set type as String.
Repeat step 4 to create 2 more attributes:

Name Type

age int

address String
Now, create a sub-class from Person. Move the mouse pointer to class Person and press on the resource icon Generalization -> Class.
Drag downwards and release the mouse button. Name the class as Employee.
Add the following attributes to the Employee class:

Name Type

employeeID String

role String
Create a class Department next to Employee class, like this:
Add the following attributes to the Department class:

Name Type

deptID String

name String
Associate Department with Employee. Move the mouse pointer to class Department and press on the resource icon Association -> Class.
Drag to Employee class and release the mouse button.
Name the roles of both ends of association. Double click at the end of association to name it.
Double click at the association end again and specify the multiplicity of both ends. Set the Department end to be 1 and the Employee end to be 1..*.
Now comes code generation. Select Tools > Java Round-trip > Generate Code... from the main menu.
Specify the source path and click OK.
Open the generated code files.
Let's edit the code file. After that, we will update the changes back to model. Add a static operation createEmployee() in the Employee class. It returns and Employee object.
Save the file and go back to VP-UML.
Select Tools > Java Round-trip > Reverse Code... from the main menu.
In the Reverse Code dialog box, uncheck Reverse source on demand and click OK. This option will cause an index tree to created instead of reversing files directly. Since we want to update the class model directly, we just uncheck it.
You can see that the operation createEmployee() is created in Employee class.