Demonstrates how to create an EMF resource loading/storing (configuration) model from/to YAML files. It can be used for creating configuration editors for Spring applications, e.g. microservices.

YamlResource.java

// --- Resource ---
public class YamlResourceImpl extends ResourceImpl {
			
	private Map<String, Object> data;
	
	public YamlResourceImpl(URI uri) {
		super(uri);
	}

	@SuppressWarnings("unchecked")
	@Override
	protected void doLoad(InputStream inputStream, Map<?, ?> options) throws IOException {
		Yaml yaml = new Yaml();
		data = (Map<String, Object>) yaml.load(inputStream); 

    // Create model content here ...
		getContents().add(content);
	}
	
	@Override
	protected void doSave(OutputStream outputStream, Map<?, ?> options) throws IOException {
		if (data == null) {
			data = new LinkedHashMap<>();
		}
		// Save to data.
		getContents()...
		
		DumperOptions dumperOptions = new DumperOptions();
		dumperOptions.setDefaultFlowStyle(FlowStyle.BLOCK);
		dumperOptions.setIndent(4);
		Yaml yaml = new Yaml(dumperOptions);
		yaml.dump(data, new OutputStreamWriter(outputStream));		
	}

}

// --- Resource factory ---
public class YamlResourceFactoryImpl extends ResourceFactoryImpl {

	@Override
	public Resource createResource(URI uri) {
		return new YamlResourceImpl(uri);
	}
	
}

// --- Resource set - in wizard and editor - simple implementation ---
ResourceSet resourceSet = new ResourceSetImpl();
						
Resource.Factory.Registry resourceFactoryRegistry = new ResourceFactoryRegistryImpl() {

	@Override
	protected Resource.Factory delegatedGetFactory(URI uri, String contentTypeIdentifier) {
		// This editor works only with YAML files which are assumed to be CCP configuration files.
		return new YamlResourceFactoryImpl();
	}

	@Override
	protected URIConverter getURIConverter() {
		return resourceSet.getURIConverter();
	}

};
						
resourceSet.setResourceFactoryRegistry(resourceFactoryRegistry);