我正在尝试使用hibernate和sessions/sessionfactory向数据库添加一行。但是，当我执行以下代码时，它只向数据库添加了一次值为“1，null”的代码。我认为问题出在productadd.java（如下）中，但我不确定。

package com.servlet;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;

import com.product.Product;
import com.utility.HibernateUtility;

@WebServlet("/ProductAdd")
public class ProductAdd extends HttpServlet {
    private static final long serialVersionUID = 1L;

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

        System.out.println("inside servlet");

        Product product= new Product(request.getParameter("prodId"),request.getParameter("prodName"));

        try {

             Product p = new Product();
             p.setName(product.getName());
             p.setId(product.getName());
             Session session = HibernateUtility.getSessionFactory().openSession();

             org.hibernate.Transaction transaction = null;

             try {

                 transaction = session.beginTransaction();
                 String sql = "INSERT INTO Product VALUES (:idVal, :nameVal)";

                 Query query = session.createSQLQuery(sql);

                 query.setParameter("idVal", product.getId());
                 query.setParameter("nameVal", product.getName());

                 query.executeUpdate();

                 session.getTransaction().commit();

             } catch (HibernateException e) {
                 transaction.rollback();
                 e.printStackTrace();

             } finally {
                 session.close();
             }

            System.out.println(("Product is added."));

        } catch (Exception e) {
            // TODO: handle exception
        }
        HttpSession session= request.getSession();

        session.setAttribute("sesname", request.getParameter("prodId"));

        response.sendRedirect("addsuccess.jsp");

    }

}

以下是my product.java（如果需要）：

package com.product;

import java.io.Serializable;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Product implements Serializable{

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private String id;
    private String name;

    public Product(String string, String string2) {
        super();
        // TODO Auto-generated constructor stub
    }
    public Product() {
        // TODO Auto-generated constructor stub
    }
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

}

我还有冬眠课：

package com.utility;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

public class HibernateUtility {
                private static final SessionFactory sessionFactory = createSessionFactory();

                public static SessionFactory createSessionFactory() {
                                try {
                                      return new AnnotationConfiguration().configure().buildSessionFactory();
                                } catch (Exception ex) {
                                                System.err.println("SessionFactory creation failed");
                                                throw new ExceptionInInitializerError(ex);
                                }
                }

                /**
                 * @return the sessionfactory
                 */
                public static SessionFactory getSessionFactory() {
                                return sessionFactory;
                }

}

以及hibernate.cfg.xml。