WorkflowInstance { public String toKey() { return workflowId().toKey() + "#" + parameter(); }  @JsonProperty abstract WorkflowId workflowId(); @JsonProperty abstract String parameter(); String toKey(); @JsonCreator static WorkflowInstance create(
      @JsonProperty("workflow_id") WorkflowId workflowId,
      @JsonProperty("parameter") String parameter); static WorkflowInstance parseKey(String key); @Override String toString(); static final Comparator<WorkflowInstance> KEY_COMPARATOR; }
@Test public void toKey() { assertThat(WORKFLOW_INSTANCE.toKey(), is(WORKFLOW_ID.toKey() + "#" + PARAMETER)); }