### Question:
FieldLayoutComponent implements FormLayoutComponent,
                                             LayoutDragComponent { @Override public IsWidget getPreviewWidget(RenderingContext ctx) { return generateContent(ctx); } @Inject  FieldLayoutComponent(FieldRendererManager fieldRendererManager, TranslationService translationService); void init(FormRenderingContext renderingContext,
                     FieldDefinition field); @Override String getDragComponentTitle(); @Override IsWidget getPreviewWidget(RenderingContext ctx); @Override IsWidget getShowWidget(RenderingContext ctx); Optional<IsWidget> getContentPart(String partId, RenderingContext componentContext); void addComponentParts(LayoutComponent component); String getFieldId(); String getFormId(); FieldRenderer getFieldRenderer(); FieldDefinition getField(); @PreDestroy void destroy();  }### Answer:
@Test public void testGetPreviewWidget() { component.getPreviewWidget(mock(RenderingContext.class)); verify(renderer).renderWidget(); verify(content).clear(); verify(content).add(any(IsWidget.class)); }