java - Hibernate 很好地插入了一个表格行，但没有删除它

我有一个网络应用程序，可以从数据库中插入和删除内容。这是我的数据库，名为“shine”:

CREATE TABLE utente (
     ID int  NOT NULL AUTO_INCREMENT,
     nome VARCHAR(255),
     cognome VARCHAR(255),
     username VARCHAR(255),
     password VARCHAR(255),
     PRIMARY KEY (ID)
);

CREATE TABLE sdplines (
    ID int NOT NULL AUTO_INCREMENT,
    value VARCHAR(255),
    session_id VARCHAR(255),
    u_id int,
    PRIMARY KEY (ID),
    FOREIGN KEY (u_id) REFERENCES utente(ID)
);

这些是我的实体:

在 SDPLines.java 中

package entities;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name = "sdplines", catalog = "shine")
public class SDPLines implements java.io.Serializable {

    @Id
    @GeneratedValue
    private int id;

    @Column(name="value")
    private String value;


    @Column(name="session_id")
    private String SessionId;


    @ManyToOne
    @JoinColumn(name="u_id")
    private Utente utente;

    public SDPLines() {

        }


    public SDPLines(String value) {

        this.value=value;

    }


    public String getValue() {
        return value;
    }


    public void setValue(String value) {
        this.value = value;
    }


    public Utente getUtente() {
        return utente;
    }


    public void setUtente(Utente utente) {
        this.utente = utente;
    }


    public String getSessionId() {
        return SessionId;
    }


    public void setSessionId(String sessionId) {
        SessionId = sessionId;
    }

在 Utente.java 中

package entities;

import java.util.Set;

// Generated 17-mar-2016 19.34.01 by Hibernate Tools 3.4.0.CR1

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;

/**
 * Utente generated by hbm2java
 */
@Entity
@Table(name = "utente", catalog = "shine")
public class Utente implements java.io.Serializable {

    @Id 
    @GeneratedValue (strategy = GenerationType.AUTO)
    @Column(name = "ID", unique = true, nullable = false)
    private long id;

    private String username;
    private String nome;
    private String cognome;
    private String password;

    @OneToMany(mappedBy="utente")
    private Set<SDPLines> sdp;

    public Utente() {
    }

    public Utente(String username) {
        this.username = username;
    }

    public Utente(String username, String nome, String cognome, String password) {
        this.username = username;
        this.nome = nome;
        this.cognome = cognome;
        this.password = password;
    }

    @Column(name = "username", unique = true, nullable = false, length = 10)
    public String getUsername() {
        return this.username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    @Column(name = "nome", length = 45)
    public String getNome() {
        return this.nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    @Column(name = "cognome", length = 45)
    public String getCognome() {
        return this.cognome;
    }

    public void setCognome(String cognome) {
        this.cognome = cognome;
    }

    @Column(name = "password", length = 45)
    public String getPassword() {
        return this.password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public long getId() {
        return id;
    }

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

    @OneToMany(mappedBy="utente")
    public Set<SDPLines> getSdp() {
        return sdp;
    }


    public void setSdp(Set<SDPLines> sdp) {
        this.sdp = sdp;
    }

}

这是管理实体的 SDPLineModel.java:

package model;

import org.hibernate.Query;

import entities.SDPLines;
import entities.Utente;

public class SDPLineModel  extends AbstractModel {

    public SDPLineModel(){

        super (Utente.class);
    }


    public SDPLines findFingerprint(String fingerprint, Long u_id){


        try{
            if(!sessionFactory.getCurrentSession().getTransaction().isActive())
                sessionFactory.getCurrentSession().getTransaction().begin();

            Query q= this.sessionFactory.getCurrentSession().createQuery("select fing from SDPLines fing where fing.value=:valore and fing.utente.id=:id");
            q.setString("valore",  fingerprint);
            q.setLong("id",u_id);

            System.out.println("eseguo la query. Valore nel DB: "+fingerprint);
            System.out.println("Fingerprint relativa a id"+u_id);

            return (SDPLines) q.uniqueResult();
        }catch(Exception e){
            e.printStackTrace();
            return null;
        }

    }

    public SDPLines loginUsername(String username){


        try{
            if(!sessionFactory.getCurrentSession().getTransaction().isActive())
                sessionFactory.getCurrentSession().getTransaction().begin();

            Query q= this.sessionFactory.getCurrentSession().createQuery("select ut from Utente ut where ut.username=:username");
            q.setString("username",  username);

            System.out.println("eseguo la query. Valore nel DB: "+username);

            return (SDPLines) q.uniqueResult();
        }catch(Exception e){
            e.printStackTrace();
            return null;
        }

    }


    public SDPLines findFingerprintNew(String fingerprint, Long user_id) {


        try{
            if(!sessionFactory.getCurrentSession().getTransaction().isActive())
                sessionFactory.getCurrentSession().getTransaction().begin();

            Query q= this.sessionFactory.getCurrentSession().createQuery("select fing from SDPLines fing where fing.value=:valore and fing.utente.id=:id");
            q.setString("valore",  fingerprint);
            q.setLong("id",user_id);

            System.out.println("eseguo la query:fingerprint= "+fingerprint);
            System.out.println("Fingerprint relativa a id= "+user_id);

            return (SDPLines) q.uniqueResult();
        }catch(Exception e){
            e.printStackTrace();
            return null;
        }

    }


    public SDPLines findFingerprintFinal(String fingerprint, String sessionid) {


        try{
            if(!sessionFactory.getCurrentSession().getTransaction().isActive())
                sessionFactory.getCurrentSession().getTransaction().begin();

            Query q= this.sessionFactory.getCurrentSession().createQuery("select fing from SDPLines fing where fing.value=:valore and fing.SessionId=:id");
            q.setString("valore",  fingerprint);
            q.setString("id",sessionid);

            System.out.println("eseguo la query:fingerprint= "+fingerprint);
            System.out.println("Fingerprint relativa a id= "+sessionid);

            return (SDPLines) q.uniqueResult();
        }catch(Exception e){
            e.printStackTrace();
            return null;
        }







    }


    public void deleteFingerprint(String fingerprint, String sessionid) {


        try{
            if(!sessionFactory.getCurrentSession().getTransaction().isActive())
                sessionFactory.getCurrentSession().getTransaction().begin();

//          Query q= this.sessionFactory.getCurrentSession().createQuery("delete fing from SDPLines fing where fing.value=:valore and fing.SessionId=:id");

            Query q= this.sessionFactory.getCurrentSession().createQuery("delete  SDPLines where value=:valore and SessionId=:id");
            q.setString("valore",  fingerprint);
            q.setString("id",sessionid);

            System.out.println("eseguo la query: DELETE fingerprint= "+fingerprint);
            System.out.println("Fingerprint relativa a id= "+sessionid+" DELETED");

        }catch(Exception e){
            e.printStackTrace();
        }   

    }

我有一个 servlet，它根据“session_id”和“value”SDPLine 值在插入和删除特定“sdplines”行之间切换。

我的问题如下:当我想在我的 mysql 数据库中存储一个新的 sdplines 行时，当我通过浏览器输入它的 session_id 和值时，这个 servlet 工作正常。但是，当我想删除一个 sdplines 行(总是从它的 session_id 和值开始)时，使用 hibernate 的 servlet 不会删除它。我只是在查询中将“选择”替换为“删除”。

这是 servlet:

package controller;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Set;

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.Session;
import org.hibernate.SessionFactory;

import entities.SDPLines;
import entities.Utente;
import model.HibernateUtil;
import model.SDPLineModel;
import model.UtenteModel;

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

    private UtenteModel um= new UtenteModel();

    public AccountController() {
        super();

    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


        String action= request.getParameter("action");

        if(action==null){
            request.getRequestDispatcher("menu.html").forward(request, response);
            }else
            {
                if(action.equalsIgnoreCase("logout")){
                    HttpSession session= request.getSession();
                    session.removeAttribute("username");
                    response.sendRedirect("AccountController");


    }
            }
    }
    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


        String action= request.getParameter("action");

        UtenteModel um= new UtenteModel();
        SDPLineModel sdpmodel= new SDPLineModel();


            if (action.equals("InsertSDPLine")) {

                HttpSession session1= request.getSession();
            //  String username = (String) session1.getAttribute("username");
            //  String password = (String) session1.getAttribute("password");

            //  Utente ut= um.loginUsername(username);

                Long user_id = (Long) session1.getAttribute("user_id");
        //      Utente ut = um.login(username, password);
                Utente ut = um.loginByID(user_id);
                Long u_id = ut.getId();

                SessionFactory sf = HibernateUtil.createSessionFactory();
                Session session = sf.openSession();
                session.beginTransaction();


                SDPLines sdp = new SDPLines(request.getParameter("sdpline"));

                sdp.setSessionId(request.getParameter("sessionid"));

                sdp.setUtente(ut);

                session.save(sdp);

                session.getTransaction().commit();
                session.close();

                String message = "INSERTED";
            //  response.addHeader("FINGERPRINT_VALIDITY", message);
                System.out.println("sdpline: "+sdp+"inserita!");
                response.getOutputStream().print(message);
                response.getOutputStream().flush();
                response.getOutputStream().close();

            }

             if (action.equals("CheckFingerprint")) {

            //  HttpSession session1= request.getSession();
            //  String username = (String) request.getParameter("username");
                String fingerprint = (String) request.getParameter("fingerprint");
                String sessionid = (String) request.getParameter("sessionid");
                //String user_id = request.getParameter("user_id");


            //  HttpSession session1= request.getSession();
            //  Long user_id = (Long) session1.getAttribute("user_id");

            //  Utente ut = um.loginByID(user_id);

            //  Utente ut= um.loginUsername(username);
            //  Utente ut = um.login(username, password);
            //  Long u_id = ut.getId();

            //  SDPLines sdpline = sdpmodel.findFingerprint(fingerprint, user_id);

            //  SDPLines sdpline = sdpmodel.findFingerprintNew(fingerprint, user_id);
                SDPLines sdpline = sdpmodel.findFingerprintFinal(fingerprint, sessionid);


                if (sdpline == null) {

                    String message = "NOT_VALID";
                //  response.addHeader("FINGERPRINT_VALIDITY", message);
                    System.out.println("Fingerprint NON trovata! ");
                    response.getOutputStream().print(message);
                    response.getOutputStream().flush();
                    response.getOutputStream().close();

                //  request.getRequestDispatcher("AfterLogin.jsp").forward(request, response); // va nella pagina welcome               
                }
                else {

                    String message = "VALID";
                    System.out.println("Fingerprint trovata! ");
                    response.getOutputStream().print(message);

                    response.getOutputStream().flush();
                    response.getOutputStream().close();
                }
            }


             if (action.equals("DeleteFingerprint")) {

            //  HttpSession session1= request.getSession();
            //  String username = (String) request.getParameter("username");
                String fingerprint = (String) request.getParameter("sdpline");
                String sessionid = (String) request.getParameter("sessionid");
                //String user_id = request.getParameter("user_id");


            //  HttpSession session1= request.getSession();
            //  Long user_id = (Long) session1.getAttribute("user_id");

            //  Utente ut = um.loginByID(user_id);

            //  Utente ut= um.loginUsername(username);
            //  Utente ut = um.login(username, password);
            //  Long u_id = ut.getId();

            //  SDPLines sdpline = sdpmodel.findFingerprint(fingerprint, user_id);

            //  SDPLines sdpline = sdpmodel.findFingerprintNew(fingerprint, user_id);
                SDPLines sdpline = sdpmodel.findFingerprintFinal(fingerprint, sessionid);


                if (sdpline == null) {

                    String message = "FINGEPRINT_NOT_PRESENT!";
                //  response.addHeader("FINGERPRINT_VALIDITY", message);
                    System.out.println("DELETE FINGEPRINT: FINGERPRINT NON PRESENTE! ");
                    response.getOutputStream().print(message);
                    response.getOutputStream().flush();
                    response.getOutputStream().close();

                //  request.getRequestDispatcher("AfterLogin.jsp").forward(request, response); // va nella pagina welcome               
                }
                else {

                    sdpmodel.deleteFingerprint(fingerprint, sessionid);

                    String message = "DELETED";
                    System.out.println("Fingerprint rimossa! ");
                    response.getOutputStream().print(message);

                    response.getOutputStream().flush();
                    response.getOutputStream().close();
                }
            }


             if(action.equals("loginUt")){

                Utente ut= um.login(request.getParameter("username"), request.getParameter("password"));
                if(ut==null){

                request.setAttribute("message","Account Invalido");
                request.getRequestDispatcher("loginUtente.jsp").forward(request, response); // rimane nella pagina della form
                }else
                {


                    HttpSession session= request.getSession();
                    session.setAttribute("username",request.getParameter("username"));

                    session.setAttribute("password",request.getParameter("password"));

                    session.setAttribute("user_id",ut.getId());

                    request.setAttribute("username",request.getParameter("username"));


//                  request.getRequestDispatcher("welcomeUtente.jsp").forward(request, response); // va nella pagina welcome
                    request.getRequestDispatcher("AfterLogin.jsp").forward(request, response); // va nella pagina welcome               
                }
        }else
        {
            if(action.equals("registra")){

                Utente ut= new Utente();

                //prelevo valori dalla form e li scrivo nel DB
                ut.setNome(request.getParameter("nome"));
                ut.setCognome(request.getParameter("cognome"));
                ut.setUsername(request.getParameter("username"));
                ut.setPassword(request.getParameter("password"));
                String password=request.getParameter("RepeatPassword");


                //registrazione nuovo utente
                this.um.create(ut);

                request.getRequestDispatcher("loginUtente.jsp").forward(request, response);

            }
        }



        }
}

这是hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.password"></property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/shine</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="hibernate.current_session_context_class">thread</property>
        <property name="show_sql">true</property>
           <mapping class="entities.SDPLines"/>
           <mapping class="entities.Utente"/> 

    </session-factory>
</hibernate-configuration>

最佳答案

好吧，似乎在您创建查询之后..您似乎并没有运行它。

在从方法返回之前添加批量更新执行，然后记得提交您的事务并关闭 session (除非您在删除后执行更多事务操作):

  Query q= this.sessionFactory.getCurrentSession()
   .createQuery("delete  SDPLines where value=:valore and SessionId=:id");
  q.setString("valore",  fingerprint);
  q.setString("id",sessionid);

  q.executeUpdate();

  session.getTransaction().commit();
}catch(Exception e){
    session.getTransaction.rollback();
}finally{
    session.close();
}

关于java - Hibernate 很好地插入了一个表格行，但没有删除它，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/42931124/

java - Hibernate 很好地插入了一个表格行，但没有删除它

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