@AssertTrue(message="company name must be unique. Company name already used")
public boolean isUniqueNameConstraint() {
IExternalCompanyDAO dao = Registry.getExternalCompanyDAO();
if (isNewObject()) {
return !dao.existsByNameInAnotherTransaction(name);
} else {
try {
ExternalCompany company =
dao.findUniqueByNameInAnotherTransaction(name);
return company.getId().equals(getId());