### Question:
OAuthJSONAccessTokenResponse extends OAuthAccessTokenResponse { @Override public Long getExpiresIn() { String value = getParam(OAuth.OAUTH_EXPIRES_IN); return value == null? null: Long.valueOf(value); } OAuthJSONAccessTokenResponse(); @Override String getAccessToken(); @Override String getTokenType(); @Override Long getExpiresIn(); String getScope(); OAuthToken getOAuthToken(); String getRefreshToken();  }### Answer:
@Test public void testGetExpiresIn() throws Exception { OAuthJSONAccessTokenResponse r = null; try { r = new OAuthJSONAccessTokenResponse(); r.init(TestUtils.VALID_JSON_RESPONSE, OAuth.ContentType.JSON, 200); } catch (OAuthProblemException e) { fail("Exception not expected"); } Assert.assertEquals(TestUtils.EXPIRES_IN, r.getExpiresIn()); initAndAssertError(r); }