@Before
public void setup() {
AssetManager assetManager = CoreRegistry.put(AssetManager.class, mock(AssetManager.class));
when(assetManager.listLoadedAssets(AssetType.PREFAB, Prefab.class)).thenReturn(Collections.<Prefab>emptyList());
EntitySystemBuilder builder = new EntitySystemBuilder();
entityManager = builder.build(moduleManager.getEnvironment(), mock(NetworkSystem.class), new ReflectionReflectFactory());
entityManager.getComponentLibrary().register(new SimpleUri("test", "gettersetter"), GetterSetterComponent.class);
entityManager.getComponentLibrary().register(new SimpleUri("test", "string"), StringComponent.class);
entityManager.getComponentLibrary().register(new SimpleUri("test", "integer"), IntegerComponent.class);