### Question:
Persistent { public static Array array() { return ARRAY; } private  Persistent(); static Object object(); static Object object(String alias); static Array array(); static final String GENERIC_TYPE; static final Null NULL; }### Answer:
@Test public void array_identity() throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException { Array a1 = Persistent.array(); Array a2 = Persistent.array(); assertThat(a1).isSameAs(a2); assertThat(a1).isEqualTo(a2); assertThat(a1).isNotEqualTo("Array()"); Constructor<Array> constructor = Array.class.getDeclaredConstructor(); constructor.setAccessible(true); Array a3 = constructor.newInstance(); assertThat(a3).isNotSameAs(a2); assertThat(a3).isEqualTo(a2); assertThat(a3.hashCode()).isEqualTo(a2.hashCode()); }
@Test public void array_to_string() { assertThat(Persistent.array().toString()).isEqualTo("Array()"); }