EntityRegionMap implements Function<String, ActorRef> { public static Builder newBuilder() { return new Builder(); } private  EntityRegionMap(final Map<String, ActorRef> rawMap); private  EntityRegionMap(final Builder builder); Optional<ActorRef> lookup(final String resourceType); @Override @Nullable ActorRef apply(final String resourceType); static EntityRegionMap singleton(final String resourceType, final ActorRef targetActor); static Builder newBuilder(); @Override boolean equals(final Object o); @Override int hashCode(); @Override String toString();  }
@Test(expected = NullPointerException.class) public void buildWithNullResourceTypeThrowsException() { EntityRegionMap.newBuilder() .put(null, createTestActorRef("ref")); }
@Test(expected = NullPointerException.class) public void buildWithNullActorRefThrowsException() { EntityRegionMap.newBuilder() .put("resourceType", null); }