Lab: UML

In this lab you will practice using the UML diagram tool Violet (see Violet in the menu to the left) to create class, sequence, and state diagrams.

Violet comes as an executable Java archive file which you can download here: violet-0.16c.jar
You must have Java installed on your machine.
On some operating systems you can launch Violet by double-clicking its icon. If that doesn't work for you, open a command window, change to the folder where your violet-0.16c.jar file is located, and run the command:
```
    java -jar violet-0.16c.jar
    
```
You should see a screen that looks like:

This section describes basic operations for class diagrams in Violet, such as creating a new diagram and manipulating its parts.

This short overview is not a complete description of Violet; it is just intended to get you started.

Dismiss the opening informational dialog and click File > New > Class Diagram to obtain the tool below. This is the tool for creating class diagrams.

All tools in Violet run in their own window. The main Violet windonw is like a mini-desktop that allows several tools running at once.

Each tool has window controls in the upper right like this:

Clicking on the left-most control will minimize the class diagram tool as shown below, with the minimized window placed at the lower left in a a task bar. Now other tools can be used. To maximize a minimized tool window, click its icon on the task bar.

Click to select the Class icon on the tool bar:

Any time a tool is selected, that is the type of diagram component (whether it is a class, relationship arrow, etc.) that will be created when you click again.

Locate a place in the window where you want to put a node (class icon), and click there. An empty rectangle will appear. You can move the node around by dragging it with the mouse. If you right-click in the rectangle you will get a Properties dialog that will allow you to enter a class name, attributes, and methods.

Experiment until you get two nodes that look like this:

Since a team is an aggregate of players, select the Aggregation icon:

Click anywhere in the Team class, and drag to anywhere in the Player class.

If the classes occupy the same horizontal strip within the diagram, you will get an edge (connecting line) like:

Click the Select icon on the tool bar:

Now drag the Player class icon down an inch or so:

All edges have a bentStyle property that defines the style of the edge.

The bentStyle of our edge is currently HVH (horizontal-vertical-horizontal).

You can control the bentStyle of an edge by right-clicking on it to get the edge's property editor:

Violet will attempt to maintain the bentStyle properties of an edge as you move associated nodes around.

Below, the Player class icon has been dragged up, but the bentStyle property of the edge is still VH (vertical-horizontal).

You can add notes to a diagram by selecting the Note icon on the tool bar:

Click anywhere in the diagram to produce a note.

Then, right-click on the note icon to get the note's property editor. You can enter the note's text and change its background color:

Finally, select the Note connector icon on the tool bar:

to connect the note to some aspect of the diagram:

Your job is to create diagrams as described in this section.

For each diagram, use the File > Save as option in Violet:

Do not use the Export image option.

In the resulting dialog, give the file the required name, leaving the Files of Type: selection set to Violet Files.

If the required name is "MyDiagram," Violet will create the full file name as "MyDiagram.violet."

Create a class diagram that looks like the one below, except that <YOUR NAME HERE> is replaced by your name.

Save your diagram as Class. Violet will actually create the file Class.violet.

Create a state diagram that looks exactly like the one below.

Note the extensive use of notes and the property editor to change a note's background color.

Save your diagram as State. Violet will actually create the file State.violet.