### Question:
IsSame implements BinaryPredicate<L, R> { public static <L, R> IsSame<L, R> instance() { return new IsSame<L, R>(); } IsSame(); boolean test(L left, R right); @Override boolean equals(Object that); @Override int hashCode(); @Override String toString(); static IsSame<L, R> instance(); static Predicate<L> as(R object); static final IsSame<Object, Object> INSTANCE; }### Answer:
@Test public void testConstant() throws Exception { assertEquals(IsSame.instance(), IsSame.instance()); assertNotSame(IsSame.instance(), IsSame.instance()); assertSame(IsSame.INSTANCE, IsSame.INSTANCE); }