IExtension applicationExtension = Platform.getExtensionRegistry().getExtension(Platform.PI_RUNTIME, Platform.PT_APPLICATIONS, applicationToRun);
IConfigurationElement[] configs = applicationExtension.getConfigurationElements();
if (configs.length == 0) throw new RuntimeException(NLS.bind(Messages.application_invalidExtension, getApplicationDescriptor().getApplicationId()));
return configs[0].createExecutableExtension("run");

IExtension extension = Platform.getExtensionRegistry().getExtension(Platform.PI_RUNTIME, Platform.PT_APPLICATIONS, applicationToRun);
Assert.isNotNull(extension, "Could not find IExtension for application: " + applicationToRun);

IConfigurationElement[] elements = extension.getConfigurationElements();
if (elements.length > 0) {
	IConfigurationElement[] runs = elements[0].getChildren("run"); //$NON-NLS-1$
	if (runs.length > 0) {
		Object runnable = runs[0].createExecutableExtension("class"); //$NON-NLS-1$
		if (runnable instanceof IApplication)
			return runnable;
	}
}

<extension id="rcp-application" point="org.eclipse.core.runtime.applications">
	<application thread="main">
		<run class="com.test.DiFramework">
			<parameter name="class" value="org.eclipse.equinox.app.IApplication"></parameter>
			<parameter name="named" value="rcp-application-sample"></parameter>
		</run>
	</application>
</extension>

public class DiFramework implements IExecutableExtension, IExecutableExtensionFactory {
	// -- parsing constants
	private final static String CLASS_NAME_PARAMETER = "class";
	private final static String NAMED_PARAMETER      = "named";
	
	/**
	 * Value from initialization
	 */
	private IConfigurationElement configuration;
	private Object data;
	private IContributor contributor;

	@Override
	public void setInitializationData(final IConfigurationElement config, final String name, final Object data) {
		// -- keep initialization value for further uses
		this.configuration = config;
		this.data          = data;
		this.contributor   = configuration.getContributor();
	}	

	@Override
	public Object create() throws CoreException {
		// -- resolve bundle
		Bundle bundle = ContributorFactoryOSGi.resolve(contributor);
		
		// -- retrieve key
		Key<?> key = retrieveKey(bundle, configuration, data);
		
		// -- create instance
		return retrieveInjector(bundle).getInstance(key);
	}
	
	/**
	 * Retrieve key from initialization value
	 * 
	 * @param bundle the bundle
	 * @param config the configuration element used to trigger this execution. 
	 *               It can be queried by the executable extension for specific configuration properties
	 * @param data adapter data in the form of a {@link String}, a {@link Hashtable}, or <code>null</code>.
	 * 
	 * @return an {@link Injector} {@link Key}
	 * 
	 * @throws CoreException if class name cannot be found or cannot be loaded
	 */
	private Key<?> retrieveKey(Bundle bundle, IConfigurationElement config, Object data) throws CoreException {
		// Retrieve class name and named
		//
		String className = null;
		String named     = null;
		
		// 1. try to query data
		//
		// -- data is a string
		if (data instanceof String) {
			className = data.toString();
		}
		// -- data is a table
		else if (data instanceof Map) {
			@SuppressWarnings("unchecked")
			Map<String, String> table = (Map<String, String>) data;
			
			// -- retrieve value, will be null if no mapping
			className = table.get(CLASS_NAME_PARAMETER);
			named     = table.get(NAMED_PARAMETER);
		}
		
		// 2. try the id of the config element
		//
		if (className == null) {
			if (config.getAttribute("id") != null) {
				className = config.getAttribute("id");
				log.debug("Found class name from config id '{}'", className);
			}
		}
		
		// -- class name not found
		if (className == null) {
			throw newCoreException("Unable to find a class name from configuration");
		}
		
		// -- load class
		final Class<?> clazz;
		try {
			clazz = bundle.loadClass(className);
		}
		catch (final InvalidRegistryObjectException e) {
			throw newCoreException(e);
		}
		catch (final ClassNotFoundException e) {
			throw newCoreException(e);
		}
		
		// -- forge key
		return named != null ? Key.get(clazz, Names.named(named)) : Key.get(clazz);
	}
}

Hello application 'com.example.MyApplication' with name 'My Application 1'

org.eclipse.core.runtime.CoreException: Unable to find a class name from configuration
	at com.example.DiFramework.newCoreException(DiFramework.java:78)
	at com.example.DiFramework.create(DiFramework.java:73)
	at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:262)
	at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:55)
	at org.eclipse.pde.internal.junit.runtime.NonUIThreadTestApplication.getApplication(NonUIThreadTestApplication.java:111)
	at org.eclipse.pde.internal.junit.runtime.NonUIThreadTestApplication.start(NonUIThreadTestApplication.java:36)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1386)