java - J2EE NetBeans em.persistance(something) 不在表中添加数据

Question

我正在用 J2EE 编写我的第一个项目。我想通过 servlet 填充数据库的一些表。例如：

这是我的实体“Administrator.java”

package cinema.entity;

import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Amministratore implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String user_name;
    private String psw;
    private String name;
    private String surname;
    private String email;
    public Administrator () {

    }
    public Administrator (String user_name, String name, String surname,String psw, String email) {
        this.user_name=user_name;        
        this.name=name;
        this.surname=surname;
        this.psw=psw;
        this.email=email;
    }

    public String getPsw () {
        return psw;
    }

    public void setPsw(String psw) {
        this.psw = psw;
    }

    public String getUserName () {
        return user_name;
    }

    public void setUserName (String user_name) {
        this.user_name=user_name;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name=name;
    }

    public String getSurname() {
        return surname;
    }
    public void setSurname(String surname) {
        this.surname=surname;
    }

    public String getEmail() {
        return email;
    }

    public void getEmail(String email) {
        this.email=email;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Amministratore)) {
            return false;
        }
        Amministratore other = (Amministratore) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "cinema.entity.Amministratore[ id=" + id + " ]";
    }
}

这是我的小服务程序：

package cinema.servlet;import cinema.entity.Administrator;
import cinema.interfacce.AdminBeanRemote;
import java.io.IOException;
import java.io.PrintWriter;
import javax.ejb.EJB;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(name = "InitializeServlet", urlPatterns = {"/InitializeServlet"})
public class InitializeServlet extends HttpServlet {

    @EJB
    AdminBeanRemote adminBean;

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();

        adminBean.cleanAdmin();
        adminBean.addNewAdmin("admin1", "Silvia", "Fichera", "admin1", "admin1@cinema.it");
        adminBean.addNewAdmin("admin2", "Giulia", "Fichera", "admin2", "admin2@cinema.it");
        adminBean.addNewGestore("gestore1", "Mike", "Bongiorno", "gestore1", "gestore1@cinema.it");
        adminBean.addNewAdmin("gestore2", "Carlo", "Conti", "gestore2", "gestore2@cinema.it");

        try {
            getServletConfig().getServletContext().getRequestDispatcher("/index.jsp").forward(request, response);
            return;
        } finally {
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    public String getServletInfo() {
        return "Short description";
    }
}

在 AdminBean 中，我有函数 cleanAdmin() 和 addNewAdmin：

package cinema.bean;

import cinema.entity.*;
import cinema.interfacce.AdminBeanRemote;
import java.util.Iterator;
import java.util.List;
import javax.ejb.Stateless;
import javax.ejb.Remote;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceException;
import javax.persistence.Query;`

@Stateless

@Remote
public class AdminBean implements AdminBeanRemote {

    @PersistenceContext
    private EntityManager em;

    @Override
    public void cleanAdmin() {
        List admin = em.createQuery("SELECT c FROM Administrator c").getResultList();
        for(Iterator iter = admin.iterator(); iter.hasNext();) {
            em.remove(iter.next());
        }
        em.flush();
    }

    @Override
    public boolean addNewAdmin(String user_name, String name, String surname, String psw,   String email)throws PersistenceException  {

        if(em.find(Administrator.class, user_name)!=null) {
            System.out.println("Admin already existing");
            return false;
        }else{
            Administrator administrator;
            administrator = new Administrator(user_name, name, surname, psw, email);
            em.persist(administrator);
        }

        return true;
    }
}

有什么建议么？我找不到文件persistance.xml，NetBeans 在其示例数据库中创建了我的表。

感谢您的帮助，如果语法不正确，我们深表歉意！