### Question:
ZipkinRequestUUIDImpl implements ZipkinRequestUUID { @Override public String getRootUUIDComponent() { return cougarUuid.getRootUUIDComponent(); } ZipkinRequestUUIDImpl(@Nonnull RequestUUID cougarUuid);  ZipkinRequestUUIDImpl(@Nonnull RequestUUID cougarUuid, @Nullable ZipkinDataBuilder zipkinDataBuilder); @Override String getRootUUIDComponent(); @Override String getParentUUIDComponent(); @Override String getLocalUUIDComponent(); @Override @Nonnull RequestUUID getNewSubUUID(); @Override @Nonnull ZipkinData getZipkinData(); @Override boolean isZipkinTracingEnabled(); @Override boolean isZipkinTracingReady(); @Override ZipkinData buildZipkinData(@Nonnull String spanName); @Override String getUUID(); @Override String toCougarLogString(); @Override String toString();  }### Answer:
@Test public void getRootUUIDComponent_ShouldDeferToCougarUUID() { String rootUUIDComponent = "abcde-1234-fghij-5678-klmno"; when(cougarUuid.getRootUUIDComponent()).thenReturn(rootUUIDComponent); victim = new ZipkinRequestUUIDImpl(cougarUuid, null); assertEquals(rootUUIDComponent, victim.getRootUUIDComponent()); }