AmazonS3Object { @Override public int hashCode() { return Objects.hash(region, bucketName, key, size, eTag, versionId); } AmazonS3Object(
      final String region,
      final String bucketName,
      final String key,
      final long size,
      @Nullable final String eTag,
      @Nullable final String versionId); String getRegion(); String getBucketName(); String getKey(); long getSize(); Optional<String> getETag(); Optional<String> getVersionId(); @Override boolean equals(final Object obj); @Override int hashCode(); @Override String toString();  }
@Test public void testHashCode() { assertThat(object.hashCode()).isEqualTo(-1614203949); }