@Override public int hashCode() { int result = contributorOrcid != null ? contributorOrcid.hashCode() : 0; result = 31 * result + (creditName != null ? creditName.hashCode() : 0); result = 31 * result + (contributorEmail != null ? contributorEmail.hashCode() : 0); result = 31 * result + (contributorAttributes != null ? contributorAttributes.hashCode() : 0); return result; } }