untuk codingan nya dibawah ini : /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package ujian.akhir.semester; import java.awt.EventQueue; import java.beans.Beans; import java.util.ArrayList; import java.util.List; import javax.persistence.RollbackException; import javax.swing.JFrame; import javax.swing.JPanel; /** * * @author User */ public class dbhewankurban extends JPanel { public dbhewankurban() { initComponents(); if (!Beans.isDesignTime()) { entityManager.getTransaction().begin(); } } /** ...