这个东西比较有趣，代码还要区分是否在Eclipse环境下运行。
先看看现象，以EMF例子Library.ecore为例, 测试代码如下：

public?class?Test?{
????public?static?void?main(String[]?args)?throws?IOException?{
????????ResourceSet?rs?=?new?ResourceSetImpl();
????????rs.getResourceFactoryRegistry().getExtensionToFactoryMap().put(
????????????????Resource.Factory.Registry.DEFAULT_EXTENSION,
????????????????new?XMIResourceFactoryImpl()); //outside eclipse
????????Resource?resource?=?rs.createResource(URI
????????????????.createURI(EXTLibraryPackage.eNS_URI));
????????//step?a
????????Library?library?=?EXTLibraryFactory.eINSTANCE.createLibrary();
????????library.setName("some?lib");
????????resource.getContents().add(library);
????????//step?b
//????????Book?book?=?EXTLibraryFactory.eINSTANCE.createBook();
//????????book.setTitle("some?book");
//????????Employee?employee?=?EXTLibraryFactory.eINSTANCE.createEmployee();
//????????employee.setFirstName("some?one");
????????//step?c
//????????library.getBooks().add(book);
//????????library.getEmployees().add(employee);
????????//step?d
//????????resource.getContents().add(book);
????
//????????System.out.println(EcoreUtil.getURI(employee));
//????????System.out.println(EcoreUtil.getURI(book));
????????resource.save(System.out,?null);
????}
}