| // Copied from org.eclipse.ocl.examples.test.xtext.PivotDocumentationExamples.java | |
| OCL ocl = OCL.newInstance(); | |
| OCLHelper helper = ocl.createOCLHelper(EXTLibraryPackage.Literals.LIBRARY); | |
| ExpressionInOCL invariant = helper.createInvariant( | |
| "books->forAll(b1, b2 | b1 <> b2 implies b1.title <> b2.title)"); | |
| ExpressionInOCL query = helper.createQuery( | |
| "books->collect(b : Book | b.category)->asSet()"); | |
| // create a Query to evaluate our query expression | |
| Query queryEval = ocl.createQuery(query); | |
| // create another to check our constraint | |
| Query constraintEval = ocl.createQuery(invariant); | |
| List<Library> libraries = getLibraries(); // hypothetical source of libraries | |
| // only print the set of book categories for valid libraries | |
| for (Library next : libraries) { | |
| if (constraintEval.check(next)) { | |
| // the OCL result type of our query expression is Set(BookCategory) | |
| @SuppressWarnings("unchecked") | |
| Set<BookCategory> categories = (Set<BookCategory>) queryEval.evaluate(next); | |
| debugPrintf("%s: %s%n\n", next.getName(), categories); | |
| } | |
| } |