public MetricDto setKey(String key) {
    this.kee = checkMetricKey(key);
    return this;
  }
@Test
  void fail_if_key_longer_than_64_characters() {
    String a65 = repeat("a", 65);

    assertThatThrownBy(() -> underTest.setKey(a65))
      .isInstanceOf(IllegalArgumentException.class)
      .hasMessage("Metric key length (65) is longer than the maximum authorized (64). '" + a65 + "' was provided.");
  }