### Question:
UtilsValidator { public static Boolean checkPresent(JsonNode jsonValue, String... keys) { for (String key : keys) { if (!jsonValue.has(key)) { return false; } } return true; }  static T get(JsonNode jsonValue, String key); static boolean isEqualTo(String a, String b); static boolean isDifferentFrom(String a, String b); static boolean isEqualTo(Number a, Number b); static boolean isDifferentFrom(Number a, Number b); static boolean isGreaterThan(Number a, Number b); static boolean isLowerThan(Number a, Number b); static boolean isGreaterThanOrEqual(Number a, Number b); static boolean isLowerThanOrEqual(Number a, Number b); static boolean isGreaterThan(Date date, int count, TimeUnit unit); static boolean isLowerThan(Date date, int count, TimeUnit unit); static boolean isGreaterThanOrEqual(Date date, int count, TimeUnit unit); static boolean isLowerThanOrEqual(Date date, int count, TimeUnit unit); static Boolean checkPresent(JsonNode jsonValue, String... keys);  }### Answer:
@Test public void checkPresent_OK() { String test = "{\"key1\": \"blablablabla toto blablabla\", \"key2\": \"tutu\",\"key3\": \"tata\",\"key4\": \"titi\" }"; JsonNode JsonNode = JSONUtils.createJsonNode(test); assertThat(UtilsValidator.checkPresent(JsonNode, "key1", "key2", "key4")).isTrue(); }
@Test public void checkPresent_KO() { String test = "{\"key1\": \"blablablabla toto blablabla\", \"key2\": \"tutu\",\"key3\": \"tata\",\"key4\": \"titi\" }"; JsonNode JsonNode = JSONUtils.createJsonNode(test); assertThat(UtilsValidator.checkPresent(JsonNode, "key1", "key2", "moi")).isFalse(); }