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Appendix C. A complete example

This appendix reproduces one model and the script that runs it, both taken unchanged from the test resources of the platform (flexo-test-resources: FML/Library.fml and AutomatedTests/TestLibrary.fmlscript). The platform's automated tests load the model and run every assert of the script, so everything below is known to parse and to behave as asserted. The tables after the listings point at the place of each construct in this specification.

C.1 The model​

use org.openflexo.foundation.fml.rt.FMLRTModelSlot as FMLRT;

import java.util.List;
import ["http://openflexo.org/test/TestResourceCenter/Library.fml/Catalog.fml"];

@URI("http://openflexo.org/test/TestResourceCenter/Library.fml")
@Version("1.0")
@Description("A library holding shelves of books")
public model Library {

	Catalog catalog;
	String lastCreatedShelf;

	public Catalog createCatalog() {
		catalog = new Catalog() with (name="catalog");
		return catalog;
	}

	public Shelf newShelf(String label) {
		Shelf shelf = new Shelf(parameters.label, 20);
		fire new ShelfCreated(parameters.label);
		return shelf;
	}

	listen ShelfCreated from this {
		lastCreatedShelf = evt.label;
	}

	event ShelfCreated {
		String label;
		create(String label) {
			label = parameters.label;
		}
	}

	public Shelf newSmallShelf(String label) {
		return new Shelf::withDefaultCapacity(parameters.label);
	}

	public List<Shelf> allShelves() {
		return select Shelf from this;
	}

	public int totalCapacity() {
		List<Shelf> shelves = select Shelf from this;
		int total = 0;
		for (int i = 0; i < shelves.size; i++) {
			total = total + shelves.get(i).capacity;
		}
		return total;
	}

	public int synchronizeIndex() {
		MatchingSet<IndexEntry> entries = begin match IndexEntry from this;
		for (Shelf shelf : select Shelf from this) {
			for (Book b : shelf.books) {
				match IndexEntry in entries from this where (book=b) unmatched: new IndexEntry(b);
			}
		}
		end match IndexEntry in entries unmatched: delete();
		List<IndexEntry> all = select IndexEntry from this;
		return all.size;
	}

	public concept IndexEntry {

		Book book;

		create(Book book) {
			book = parameters.book;
		}

		delete() {
		}
	}

	public abstract concept Publication {

		abstract String code;
	}

	public concept Shelf {

		String label;
		int capacity;
		Book[0,*] books;
		int bookCount values books.size;
		private String notes;

		String displayName {
			String get() {
				return "Shelf " + label;
			}
			set(String value) {
				label = value;
			}
		};

		create(required String label, int capacity=10) {
			label = parameters.label;
			capacity = parameters.capacity;
		}

		create::withDefaultCapacity(String label) {
			label = parameters.label;
			capacity = 10;
		}

		delete() {
		}

		@UI(
			@TextField(value="title", label="book_title")
		)
		public Book newBook(required String title) {
			Book book = new Book(parameters.title);
			books.add(book);
			return book;
		}

		public Novel newNovel(String title, String author) {
			Novel novel = new Novel(parameters.title, parameters.author);
			books.add(novel);
			return novel;
		}

		public rename(String newName) {
			displayName = parameters.newName;
		}

		public int countNovels() {
			int count = 0;
			for (Book book : books) {
				if (book instanceof Novel) {
					count = count + 1;
				}
			}
			return count;
		}

		public Book findBook(String title) {
			for (Book book : books) {
				if (book.title == parameters.title) {
					return book;
				}
			}
			return null;
		}

		public Book findBookByTitle(String title) {
			return select unique Book from (this) where (selected.title == parameters.title);
		}

		public int freeSlots() {
			int free = 0;
			int filled = bookCount;
			while (filled < capacity) {
				filled = filled + 1;
				free = free + 1;
			}
			return free;
		}

		public removeBook(Book book) {
			books.remove(parameters.book);
			delete parameters.book;
		}

		public concept Book extends Publication {

			String title;
			String code values "B-" + title;

			create(String title) {
				title = parameters.title;
			}

			delete() {
			}
		}

		public concept Novel extends Book {

			String author;

			create(String title, String author) {
				super(parameters.title);
				author = parameters.author;
			}

			delete() {
			}
		}
	}
}

C.2 Where each construct is specified​

In the modelConstructSection
use … as FMLRT;technology-adapter alias§3.4
import java.util.List;Java import§3.5.1
import ["…/Catalog.fml"];import of a contained model by address§3.5.2, §5.1.4
@URI, @Version, @Descriptionannotations on a model§11.3
public model Librarymodel declaration§5.1
Catalog catalog;property typed with a contained model§6.1
new Catalog() with (name="catalog")instantiating a model§9.7
event ShelfCreated, fire, listen … from this, evtevents§5.5, §10.6, §7.7
new Shelf::withDefaultCapacity(…)named creation scheme§7.3.1
select Shelf from thisquery§10.2
for (int i = 0; i < shelves.size; i++)classic for, property access size§8.5, §9.6
begin match … end matchmatching set§10.9
public abstract concept Publication, abstract String code;abstract concept and property§5.2.2, §6.6
Book[0,*] books;multi-valued property§4.6, §6.3
int bookCount values books.size;expression property§6.4
String displayName { … };get/set property§6.7
private String notes;visibility§5.8
create(required String label, int capacity=10)creation scheme, required argument, default§7.2, §7.3.1
create::withDefaultCapacitynamed creation scheme§7.3.1
delete() { }deletion scheme§7.3.2
@UI(@TextField(…))annotation on a behaviour§11.5
books.add(book), books.remove(…)multi-valued property§6.3
select unique Book from (this) where (selected.title == …)single-result query§10.2
while (filled < capacity)loop§8.5
book instanceof Noveltype test§9.9
delete parameters.book;deletion§10.4
public concept Book extends Publicationnesting and inheritance§5.2.1, §5.3
super(parameters.title)parent creation scheme§5.3.2
parameters.titleargument access§7.2.1

C.3 The script​

virtualModel = load -r ["http://openflexo.org/test/TestResourceCenter/Library.fml"];
assert virtualModel != null;
assert virtualModel.name == "Library";

// Nested concepts: Book and Novel live in Shelf, which is a root concept
shelf = virtualModel.getFlexoConcept("Shelf");
assert shelf != null;
book = virtualModel.getFlexoConcept("Book");
assert book != null;
assert shelf.isRoot();
assert book.isRoot() == false;
assert book.containerFlexoConcept == shelf;
assert book.getURI() == "http://openflexo.org/test/TestResourceCenter/Library.fml#Shelf#Book";

// Concept inheritance: Novel extends Book
novel = virtualModel.getFlexoConcept("Novel");
assert novel != null;
assert book.isSuperConceptOf(novel);

// Contained VirtualModel: Catalog is stored in Library.fml/, its URI is computed from Library's one
assert virtualModel.getVirtualModels(true).size == 1;
assert virtualModel.getVirtualModels(true).get(0).getURI() == "http://openflexo.org/test/TestResourceCenter/Library.fml/Catalog.fml";
catalog = load -r ["http://openflexo.org/test/TestResourceCenter/Library.fml/Catalog.fml"];
assert catalog != null;
assert catalog.containerVirtualModel == virtualModel;

// Run-time
service ResourceCenterService add_temp_rc;
library = new Library() with (name="library");
assert library != null;

// Inside a behaviour of Library, "new Catalog() with (name=...)" creates a VirtualModelInstance of the
// contained VirtualModel, itself contained in the Library instance
libraryCatalog = library.createCatalog();
assert libraryCatalog != null;
assert libraryCatalog.name == "catalog";
assert libraryCatalog.containerVirtualModelInstance == library;
assert library.catalog == libraryCatalog;

// Creation scheme with a required parameter and a parameter declaring a default value
shelfCreation = shelf.getCreationSchemes().get(0);
assert shelfCreation.getSignature() == "create(label,capacity)";
assert shelfCreation.getParameter("label").getIsRequired();
assert shelfCreation.getParameter("capacity").getIsRequired() == false;
fiction = library.newShelf("Fiction");
assert fiction != null;
assert fiction.label == "Fiction";
// newShelf fires a ShelfCreated event, received by the listener declared in Library
assert library.lastCreatedShelf == "Fiction";
assert fiction.capacity == 20;
assert library.allShelves().size == 1;

// Inside a behaviour of Shelf, "new Book(...)" creates a Book contained in that Shelf instance
emma = fiction.newBook("Emma");
assert emma != null;
assert emma.title == "Emma";
assert emma.container == fiction;

dune = fiction.newNovel("Dune", "Frank Herbert");
assert dune != null;
assert dune.title == "Dune";
assert dune.author == "Frank Herbert";
assert dune.container == fiction;

// Concept instance role with multiple cardinality, and expression property (read-only)
assert shelf.getDeclaredProperty("books").cardinality.toString() == "ZeroMany";
assert shelf.getDeclaredProperty("bookCount").isReadOnly();
assert shelf.getDeclaredProperty("label").getURI() == "http://openflexo.org/test/TestResourceCenter/Library.fml#Shelf.label";
assert fiction.books.size == 2;
assert fiction.bookCount == 2;

// Get/set property: the getter computes, the setter (called by rename) writes the label
assert fiction.displayName == "Shelf Fiction";
fiction.rename("Classics");
assert fiction.label == "Classics";
assert fiction.displayName == "Shelf Classics";

// Iteration and conditional
assert fiction.countNovels() == 1;

// Early return from an iteration
assert fiction.findBook("Dune") == dune;
assert fiction.findBook("Ulysses") == null;

// Fetch request with a where clause
assert fiction.findBookByTitle("Emma") == emma;
assert fiction.findBookByTitle("Ulysses") == null;

// While loop
assert fiction.freeSlots() == 18;

// Abstract property: Publication declares code, Book implements it with an expression property
publication = virtualModel.getFlexoConcept("Publication");
assert publication != null;
assert publication.isAbstract();
assert publication.isSuperConceptOf(book);
assert emma.code == "B-Emma";
assert dune.code == "B-Dune";

// Named creation scheme, reached with new Shelf::withDefaultCapacity(...)
small = library.newSmallShelf("Poetry");
assert small != null;
assert small.label == "Poetry";
assert small.capacity == 10;

// Classic for loop, over the shelves Fiction (20) and Poetry (10)
assert library.totalCapacity() == 30;

// Matching: one index entry per book; running the synchronization again creates no duplicate
assert library.synchronizeIndex() == 2;
assert library.synchronizeIndex() == 2;

// Deletion: the book is removed from the multiple role, then deleted
fiction.removeBook(emma);
assert fiction.books.size == 1;

// Matching: the entry of the deleted book is not matched any more, and is deleted by end match
assert library.synchronizeIndex() == 1;
assert fiction.findBook("Emma") == null;

// Visibility: no keyword means Default
assert shelf.getDeclaredProperty("notes").visibility.toString() == "Private";
assert shelf.getDeclaredProperty("label").visibility.toString() == "Default";

log "Test PASSED: Library instantiates, with nested and inherited concepts, properties, parameters and control structures";

C.4 Reading the script​

Part of the scriptWhat it showsSection
load -r […]loading returns the virtual model§12.3
getFlexoConcept("Shelf"), isRoot(), containerFlexoConceptthe model level can be inspected§13.1
service ResourceCenterService add_temp_rc;a writable resource center§12.5
new Library() with (name="library")instantiating a model§12.5
fiction.books.size == 2a multi-valued property is a list§6.3
emma.container == fictioncontainment at run time§13.2
library.lastCreatedShelf == "Fiction"event delivered synchronously§10.6
fiction.displayName == "Shelf Fiction"get/set property§6.7
fiction.freeSlots() == 18a while loop in a behaviour§8.5
library.synchronizeIndex() == 2 run twicea re-runnable matching§10.9, §13.11
shelf.getDeclaredProperty("notes").visibility.toString() == "Private"visibility is metadata§5.8