### Question:
PayloadImpl implements Payload, Serializable { Map<String, JsonNode> getTree() { return tree; } PayloadImpl(String issuer, String subject, List<String> audience, Date expiresAt, Date notBefore, Date issuedAt, String jwtId, Map<String, JsonNode> tree, ObjectReader objectReader); @Override String getIssuer(); @Override String getSubject(); @Override List<String> getAudience(); @Override Date getExpiresAt(); @Override Date getNotBefore(); @Override Date getIssuedAt(); @Override String getId(); @Override Claim getClaim(String name); @Override Map<String, Claim> getClaims();  }### Answer:
@SuppressWarnings("Convert2Diamond") @Test public void shouldHaveUnmodifiableTree() throws Exception { exception.expect(UnsupportedOperationException.class); PayloadImpl payload = new PayloadImpl(null, null, null, null, null, null, null, new HashMap<String, JsonNode>(), objectReader); payload.getTree().put("something", null); }