### Question:
PolicyEnforcementFilter extends GenericHeapObject implements Filter { @VisibleForTesting static String createKeyCache(final String ssoToken, final String jwt, final String requestedUri) { return new StringBuilder(requestedUri).append(ifSpecified(ssoToken)).append(ifSpecified(jwt)).toString(); } @VisibleForTesting  PolicyEnforcementFilter(final URI baseUri, final Handler policiesHandler);  PolicyEnforcementFilter(final URI baseUri,
                                   final Handler policiesHandler,
                                   final Duration cacheMaxExpiration); void setCache(final ThreadSafeCache<String, Promise<JsonValue, ResourceException>> cache); @Override Promise<Response, NeverThrowsException> filter(final Context context,
                                                          final Request request,
                                                          final Handler next); void setApplication(final String application); void setSsoTokenSubject(final Expression<String> ssoTokenSubject); void setJwtSubject(final Expression<String> jwtSubject);  }### Answer:
@Test(dataProvider = "givenAndExpectedKey") public void shouldSucceedToCreateCacheKey(final String requestedUri, final String ssoToken, final String jwt, final String expected) { assertThat(createKeyCache(ssoToken, jwt, requestedUri)).isEqualTo(expected); }