Code for a default generated JPA entity looks like:

package org.svcc;

import java.io.Serializable;
import javax.persistence.*;

/**

• Entity implementation class for Entity: Student
  *
  */
  @Entity

public class Student implements Serializable {

private static final long serialVersionUID = 1L;

public Student()

}

This is an invalid entity because each JPA entity must have a primary key.

For a simpler OOTB experience, generate a default primary key.