@Test
  public void shouldValidateJSONObject() {
    assertTrue(StringUtils.isJsonObject("{\"a\":true}"));
    assertTrue(StringUtils.isJsonObject("[0, 1, 2]"));
    assertTrue(StringUtils.isJsonObject("true"));
    assertTrue(StringUtils.isJsonObject("false"));
    assertTrue(StringUtils.isJsonObject("null"));
    assertTrue(StringUtils.isJsonObject("1"));
    assertTrue(StringUtils.isJsonObject("-1"));
  }
A dummy key which is longer than allowed.
src/test/java/net/spy/memcached/util/StringUtilsTest.java