Add Constructor to UML Class
What is a Constructor in UML Class Diagram?
A constructor is an operation within a UML class. It is annotated with «create» stereotype. A constructor is a special operation (or method) that is used to initialize a class instance. A constructor may be parameterless or it may include a list of parameters that have to be set to initialize a class instance properly.
How to Add a Constructor?
- Select a class to which you want to add a constructor.
- Click on Add Constructor in the context bar.
- New Constructor dialog will show. In the dialog, choose the attributes you want to include in the constructor as its parameters.
- Click on OK to confirm the dialog and insert the new constructor.
Various Methods of Constructor Creation
Consider a class in your diagram with several properties or attributes. There are several methods you can add a constructor to the class.
Method 1: Manual Constructor Addition
- Add a new operation to your class.
- Name this operation after the class itself and add a 'create' stereotype.
- This method is simple but might become less efficient if your constructor requires multiple parameters.
Method 2: Using the 'Add Constructor' Context Button
This method is more efficient, especially for constructors with numerous parameters.
- Select the class in your diagram. A context bar will appear under the selected class.
- Find and click the 'Add Constructor' button in this context bar.
- A dialog box will open, allowing you to select which attributes to initialize in the constructor. You can also add more parameters later in the diagram editor.
- After making your choices, click 'OK' to confirm and add the constructor to the class.
Method 3: Shortcut Key Method
Adding constructors using shortcut keys is a quick alternative.
- Use the relevant shortcut key that corresponds to the constructor button in the context bar - in our case, it is the fourth button, so we press ALT+4.
- This opens the 'New Constructor' dialog.
- In the dialog, use the 'Select All' option to choose all attributes, and then click 'OK'.
- This action will create a new constructor that initializes all chosen attributes and adds it to the class operations list.