### Question:
DiagramTypeClientProjectService implements DiagramTypeClientService { @Override public ProjectType getProjectType(final Metadata metadata) { return Optional.ofNullable(projectTypeRegistry.get(getDiagramId(metadata))) .orElse(ProjectType.BPMN); } DiagramTypeClientProjectService(); @Inject  DiagramTypeClientProjectService(Caller<BPMNDiagramService> bpmnDiagramService); @Override void loadDiagramType(Metadata metadata); @Override ProjectType getProjectType(final Metadata metadata);  }### Answer:
@Test public void getNull() { ProjectType projectType = tested.getProjectType(metadata); assertThat(projectType).isEqualTo(ProjectType.BPMN); }