/**
  * Creates an "equals" Criterion based on the specified property name and value.
  *
  * @param propertyName The property name
  * @param propertyValue The property value
  * @return A Criterion instance
  */
 public Criteria eq(String propertyName, Object propertyValue) {
   validatePropertyName(propertyName, "eq");
   addToCriteria(Restrictions.eq(propertyName, propertyValue));
   return this;
 }
 @Override
 public Query.Criterion createCriterion() {
   return Restrictions.eq(propertyName, arguments[0]);
 }