### Question:
IsElementOf implements BinaryPredicate<L, R> { @Override public boolean equals(Object obj) { return (obj instanceof IsElementOf<?, ?>); } IsElementOf(); boolean test(L obj, R col); @Override boolean equals(Object obj); @Override int hashCode(); @Override String toString(); static IsElementOf<Object, Object> instance(); static Predicate<A> instance(Object obj);  }### Answer:
@Test public void testEquals() throws Exception { IsElementOf<Integer, Collection<Integer>> p1 = new IsElementOf<Integer, Collection<Integer>>(); assertObjectsAreEqual(p1, p1); assertObjectsAreEqual(p1, new IsElementOf<Integer, Collection<Integer>>()); assertObjectsAreEqual(p1, IsElementOf.instance()); assertSame(IsElementOf.instance(), IsElementOf.instance()); assertObjectsAreNotEqual(p1, Constant.falsePredicate()); }