@Test
  public void testSuccessiveRestrictToFips_works() throws Exception {
    Assume.assumeTrue(TinkFipsUtil.fipsModuleAvailable());
    Registry.reset();
    Registry.restrictToFipsIfEmpty();
    Registry.restrictToFipsIfEmpty();
    Registry.restrictToFipsIfEmpty();
    assertTrue(TinkFipsUtil.useOnlyFips());
  }
Returns the type URL that identifies the key type of keys managed by this KeyManager.
java_src/src/test/java/com/google/crypto/tink/RegistryTest.java