code: private static Renderer createRenderer(final String rendererName) {
  		if (rendererName.endsWith(".vm")) {
  			// This is a velocity template, so use a VelocityLayout
  			return new VelocityRenderer(rendererName);
  		}
  
  		try {
  			Class<?> managerClass = Class.forName(rendererName);
  			Object manager = managerClass.newInstance();
  
  			if (!(manager instanceof Renderer)) {
  				throw new SystemException(rendererName + " is not a Renderer");
  			}
  
  			return (Renderer) manager;
  		} catch (ClassNotFoundException e) {
  			// Legal - there might not a manager implementation in a given theme
  			return null;
  		} catch (InstantiationException e) {
  			throw new SystemException("Failed to instantiate " + rendererName, e);
  		} catch (IllegalAccessException e) {
  			throw new SystemException("Failed to access " + rendererName, e);
  		}
  	}
docs: Attempts to create a Renderer with the given name.
  
  @param rendererName the name of the Renderer
  @return a Renderer of the given type, or null if the class was not found.