| import ecore : 'http://www.eclipse.org/emf/2002/Ecore#/'; |
| |
| package tutorial : tut = 'http://www.eclipse.org/mdt/ocl/oclinecore/tutorial' |
| { |
| class Library |
| { |
| attribute name : String; |
| property books#library : Book[*] { composes }; |
| property loans : Loan[*] { composes }; |
| property members#library : Member[*] { composes }; |
| } |
| |
| class Book |
| { |
| invariant SufficientCopies: |
| library.loans->select(book=self)->size() <= copies; |
| attribute name : String; |
| attribute copies : Integer; |
| property library#books : Library[?]; |
| property loans : Loan[*] { derived,volatile } |
| { |
| derivation: library.loans->select(book=self); |
| } |
| operation isAvailable() : Boolean[?] |
| { |
| body: loans->size() < copies; |
| } |
| } |
| |
| class Member |
| { |
| invariant AtMostTwoLoans: |
| loans->size() <= 2; |
| invariant UniqueLoans: |
| loans->isUnique(book); |
| attribute name : String; |
| property library#members : Library[?]; |
| property loans : Loan[*] { derived,volatile } |
| { |
| derivation: library.loans->select(member=self); |
| } |
| property books : Book[*] { derived,volatile,!unique } |
| { |
| derivation: loans->collect(book); |
| } |
| } |
| |
| class Loan |
| { |
| property book : Book; |
| property member : Member; |
| attribute date : ecore::EDate[?]; |
| } |
| } |
| |
