EPackage

struct EPackage

Overview

EPackage is a container for classifiers (classes, data types, enums) and provides a namespace for metamodel elements. Packages are the top-level organisational unit in Ecore, similar to packages in Java or modules in Swift.

Each package has:

• Namespace URI (nsURI): Unique identifier for the package across systems

• Namespace Prefix (nsPrefix): Short prefix used in XML serialisation

• Classifiers: The types (classes, data types, enums) defined in this package

• Subpackages: Nested packages for hierarchical organisation

Example

let companyPackage = EPackage(
    name: "company",
    nsURI: "http://example.org/company",
    nsPrefix: "company",
    classifiers: [
        EClass(name: "Employee"),
        EClass(name: "Department")
    ]
)

// Look up a classifier
if let employee = companyPackage.getClassifier("Employee") as? EClass {
    print("Found class: \(employee.name)")
}

Namespace URIs

The namespace URI uniquely identifies the package across different systems and versions. By convention, it uses a reverse domain name format:

• http://www.eclipse.org/emf/2002/Ecore - The Ecore metamodel itself

• http://example.org/mymodel - Custom metamodel

XML Namespace Prefixes

The namespace prefix is used in XMI serialisation to abbreviate element names:

<company:Employee xmlns:company="http://example.org/company" name="Alice"/>