### Question:
SlotState { public String toString() { return new StringBuilder().append(granularity == null ? "null" : granularity.name()) .append(",").append(slot) .append(",").append(state == null ? "null" : state.code()) .append(": ").append(getTimestamp() == null ? "" : getTimestamp()) .toString(); } SlotState(Granularity g, int slot, UpdateStamp.State state);  SlotState(); SlotState withTimestamp(long timestamp); SlotState withLastUpdatedTimestamp(long lastUpdatedTimestamp); String toString(); boolean equals(Object other); Granularity getGranularity(); int getSlot(); UpdateStamp.State getState(); Long getTimestamp(); long getLastUpdatedTimestamp();  }### Answer:
@Test public void testStringConversion() { Assert.assertEquals(s1 + ": ", ss1.toString()); Assert.assertEquals(s2 + ": " + time, ss2.toString()); Assert.assertEquals(s3 + ": " + time, ss3.toString()); }