book3.setTitle("Book 3");
book3.setPages(3000);
book3.setCategory(BookCategory.BIOGRAPHY_LITERAL);
fixture.getBooks().add(book3);
Writer writer1 = LibraryFactory.eINSTANCE.createWriter();
writer1.setName("Writer 1");
writer1.getBooks().add(book1);
fixture.getWriters().add(writer1);
Writer writer2 = LibraryFactory.eINSTANCE.createWriter();
writer2.setName("Writer 2");
writer2.getBooks().add(book2);
writer2.getBooks().add(book3);
fixture.getWriters().add(writer2);
// add some anonymous content to the resource
// e.g., an XML document consisting of
// <test xmlns="urn:test">