@Override
  public String generate() {
    return UUID.randomUUID().toString();
  }
@Test
  public void generate_shouldGenerateUniqueIds() {
    String requestId1 = requestIdGenerator.generate();
    String requestId2 = requestIdGenerator.generate();
    String requestId3 = requestIdGenerator.generate();

    assertThat(requestId1).isNotEqualTo(requestId2).isNotEqualTo(requestId3);
  }