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Class Diagrams

UML class diagrams are a handy way to define object-oriented types. MontiArc has an integration for class diagrams written with cd4code (a language extension of cd4analysis). cd4code features the definition of

  • Enums
  • Interfaces
  • Classes
  • Abstract classes
  • Field members
  • Method members
  • Associations between classes, also featuring cardinalities
  • Package structures
package corp;
import java.util.Date;

classdiagram MyCompany {

  enum CorpKind { SOLE_PROPRIETOR, S_CORP, C_CORP, B_CORP, CLOSE_CORP, NON_PROFIT; }
  abstract class Entity;
  package people {
    class Person extends Entity {
      Date birthday;
      List<String> nickNames;
      -> Address [*] {ordered};
    }
    class Address {
      String city;
      String street;
      int number;
    }
  }
  class Company extends Entity {
    CorpKind kind;
  }
  class Employee extends people.Person {
    int salary;
  }
  class Share {
    int value;
  }
  association [1..*] Company (employer) <-> Employee [*];
  composition [1] Company <- Share [*];
  association shareholding [1] Entity (shareholder) -- (owns) Share [*];
}

Comprehensive information

You can find comprehensive information on how to define types with cd4code here. Moreover, there are several examples of cd4code models.

Special behavior of class diagram usage in MontiArc

There are some things that you should note when working with object-oriented types in MontiArc:

Packages

Class diagrams themselves are defined within a package structure. However, they themselves also span a new package. E.g., take the following class diagram model: 

package com.example;

classdiagram fingerprotection {
  public enum FingerProtectionOrder {
    PROTECT, PROTECTION_OFF;
  }
}
The FingerProtectionOrder type will be located in the com.example.fingerprotection package. Note that the class diagram name becomes a part of the package name. To use the type in MontiArc, one would be importing it at the beginning of the MontiArc model: 
package com.example.window;

import com.example.fingerprotection.FingerProtectionOrder;

component WindowController { /*...*/ }

Calling constructors

compute {
  personOutPort = Person.Person("Steven");
}
When calling constructors of object-oriented types in MontiArc, one calls the constructor as if it were a method of the defining type: 
TypeName.methodName(/*arguments*/)
As the constructor method name is the same as the type name, this syntax becomes 
TypeName.TypeName(/*arguments*/)