### Question:
HmacKey implements Key { public String getId() { return keyId; } HmacKey(String keyId, String secret); String getId(); Set<Algorithm> getAlgorithms(); boolean canVerify(); boolean verify(Algorithm algorithm, byte[] contentBytes, byte[] signatureBytes); boolean canSign(); byte[] sign(Algorithm algorithm, byte[] contentBytes);  }### Answer:
@Test public void shouldReturnSuppliedId() throws Exception { assertThat(new HmacKey("myId", "").getId(), is("myId")); }