@Override
    public boolean isJson(String text) {
        try {
            MAPPER.readTree(text);
            return true;
        } catch (JsonProcessingException ignored) {
        }
        return false;
    }
@Test
    public void testIsJson() {
        // normal json
        Assertions.assertTrue(JACKSON_HANDLER.isJson(EXPECTED_ENTITY_JSON));
        Assertions.assertTrue(JACKSON_HANDLER.isJson(EXPECTED_ENTITY_ARRAY_JSON));
        Assertions.assertTrue(JACKSON_HANDLER.isJson(" "));
        // illegal json
        Assertions.assertFalse(JACKSON_HANDLER.isJson("{" +
                "\"id\":1," +
                "\"name\":\"entity1\"," +
                "\"entity\":{\"id\":2,\"name\":\"entity2\"}"));
        // null json
        Assertions.assertThrows(IllegalArgumentException.class, () -> JACKSON_HANDLER.isJson(null));
    }