Set provides an unordered data structure, and duplicate elements are not allowed. Some classes implemented by the
Set interface are
java.util.LinkedHashSet, and so on. For this recipe, we will use the
java.util.HashSet class, which implements the
java.util.Set interface. The only difference between
Set is that
Set doesn't allow duplicate values. For example, in our previous example, we added the e-mail address with
firstname.lastname@example.org twice, and hibernate will allow us to do this. But in case of
Set, you cannot add a duplicate value. Let's take a look at how to achieve this.
Now, we need the class to persist
Set in hibernate. Use the next code snippet to create the
Employee class. ...