JPA Composite Key + Sequence

Question

Is it possible in plain JPA or JPA+Hibernate extensions to declare a composite key, where an element of the composite key is a sequence?

This is my composite class:

Answer 1

Try like this:

@TableGenerator(name = "canonicalKeys", allocationSize = 1, initialValue = 1)
@GeneratedValue(strategy = GenerationType.TABLE, generator = "canonicalKeys")
@Column(name = "CANONICAL_ID", unique = false, nullable = false, insertable = true, updatable = true)
public String getCanonicalId() {
    return canonicalId;
}

In this way instead of using a sequence you can use a table.