在几个选择查询或插入查询后休眠挂起答案

【问题标题】：Hibernate hangs after several select queries or insert queries在几个选择查询或插入查询后休眠挂起
【发布时间】：2016-08-09 12:39:31
【问题描述】：

我正在使用 Hibernate 关系开发 Spring 和 Hibernate Web 应用程序，它可以正常工作 3 次，并且从数据库中获取记录没有问题，但是在 4 次应用程序挂起或冻结时，当我重新启动 tomcat 服务器时，一切正常很好，尝试 4 次后再次挂起或冻结。当应用程序挂起或冻结让我很困惑时，没有错误。当我测试另一个在 Hibernate 上不使用关系运行良好的类时，我怀疑是关系，但我不知道~

这是我的 Hibernate 关系参考 ~

mkyong

viralpatel

这是我的任务，

这是我的用户类，

@SuppressWarnings("serial")
@Entity
@Table(name="user")
public class User implements Serializable{

private String no_dana;
private String npp;

@Id
@Column(name="no_dana", unique=true, nullable=false, updatable=false)
public String getNo_dana() {
    return no_dana;
}
public void setNo_dana(String no_dana) {
    this.no_dana = no_dana;
}
@Column(name="npp")
public String getNpp() {
    return npp;
}
private Set<Tanya> tanya;

@OneToMany(fetch= FetchType.LAZY, cascade=CascadeType.ALL, mappedBy="user")
public Set<Tanya> getTanya() {
    return tanya;
}
public void setTanya(Set<Tanya> tanya) {
    this.tanya = tanya;
}

private Set<Jawab> jawab;

@OneToMany(fetch = FetchType.LAZY, mappedBy="user")
public Set<Jawab> getJawab() {
    return jawab;
}
public void setJawab(Set<Jawab> jawab) {
    this.jawab = jawab;
}
}

这是我的 tanya 课，

@SuppressWarnings("serial")
@Entity
@Table(name="tanya")
public class Tanya implements Serializable{

private int id_tanya;
private String isi;

@Id
@Column(name="id_tanya", unique=true, nullable=false)
public int getId_tanya() {
    return id_tanya;
}
public void setId_tanya(int id_tanya) {
    this.id_tanya = id_tanya;
}
@Column(name="isi")
public String getIsi() {
    return isi;
}
public void setIsi(String isi) {
    this.isi = isi;
}
private User user;

@ManyToOne(cascade=CascadeType.ALL)
@JoinColumn(name="no_dana")
public User getUser() {
    return user;
}
public void setUser(User user) {
    this.user = user;
}

private Set<Jawab> jawab;

@OneToMany(fetch = FetchType.LAZY, mappedBy="tanya")
public Set<Jawab> getJawab() {
    return jawab;
}
public void setJawab(Set<Jawab> jawab) {
    this.jawab = jawab;
}
}

这是我的下巴班，

@SuppressWarnings("serial")
@Entity
@Table(name="jawab")
public class Jawab implements Serializable{

private int id_jawab;
private String isi;

@Id
@Column(name="id_jawab", unique=true, nullable=false)
public int getId_jawab() {
    return id_jawab;
}
public void setId_jawab(int id_jawab) {
    this.id_jawab = id_jawab;
}
@Column(name="isi")
public String getIsi() {
    return isi;
}
public void setIsi(String isi) {
    this.isi = isi;
}

private User user;

@ManyToOne(cascade=CascadeType.ALL)
@JoinColumn(name="no_dana")
public User getUser() {
    return user;
}
public void setUser(User user) {
    this.user = user;
}

private Tanya tanya;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name="id_tanya")
public Tanya getTanya() {
    return tanya;
}
public void setTanya(Tanya tanya) {
    this.tanya = tanya;
}
}

这是我的 dao 示例（来自 tanya 类），

@Autowired
private TanyaDaoImpl(SessionFactory sessionFactory){
    setSessionFactory(sessionFactory);
}

@SuppressWarnings("unchecked")
@Override
public Tanya get(int id_tanya)throws Exception{
    DetachedCriteria criteria = DetachedCriteria.forClass(Tanya.class).add(Restrictions.eq("id_tanya", id_tanya));
    List<Tanya> tanyaList = getHibernateTemplate().findByCriteria(criteria);
    return tanyaList.get(0);
}

@Override
public Tanya getTanya(int id_tanya)throws Exception{
    Query query = getSession().createQuery("from Tanya where id_tanya = :id_tanya");
    query.setParameter("id_tanya", id_tanya);
    return (Tanya) query.list().get(0);
}

@Override
public void save(Tanya tanya)throws Exception{
    getHibernateTemplate().save(tanya);
}

@Override
public void update(Tanya tanya)throws Exception{
    getHibernateTemplate().update(tanya);
}

@Override
public void delete(Tanya tanya)throws Exception{
    getHibernateTemplate().delete(tanya);
}

@SuppressWarnings("unchecked")
@Override
public List<Tanya> listAllTanya()throws Exception{
    DetachedCriteria criteria = DetachedCriteria.forClass(Tanya.class);
    List<Tanya> tanyaList = getHibernateTemplate().findByCriteria(criteria);
    return tanyaList;
}

这是我的会话配置，

<context:component-scan base-package="org.ppbni.splatter" />
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
    destroy-method="close">
    <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url" value="jdbc:mysql://localhost:3306/db_ppbni" />
    <property name="username" value="root" />
    <property name="password" value="shikamaru" />

    <!-- <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url" value="jdbc:mysql://localhost:3306/ppbniorg_db" />
    <property name="username" value="ppbniorg_user" />
    <property name="password" value="shikamaru" /> -->

</bean>
<bean id="sessionFactory"
    class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
    <property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration"></property>
    <property name="dataSource" ref="dataSource"></property>
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
            <prop key="hibernate.show_sql">true</prop>
        </props>
    </property>
    <property name="packagesToScan" value="org.ppbni.splatter.model" />
</bean>

<bean id="transactionManager"
    class="org.springframework.orm.hibernate3.HibernateTransactionManager"
    p:sessionFactory-ref="sessionFactory">
</bean>

任何帮助都会很高兴 :D ~

【问题讨论】：

能否也补充一下如何指定dataSource bean？
@alobodzk 我已经更新了我的问题，请查看~

标签： java mysql spring hibernate

【解决方案1】：

这可能是因为以前的会话。在成功的事务后使用 session.close() 方法关闭会话，这将释放连接到数据库的实例。由于这种方法，问题得到了纠正。

session.close();

https://docs.jboss.org/hibernate/orm/3.5/javadocs/org/hibernate/Session.html#close()

【讨论】：

【解决方案2】：

我不知道什么会导致间歇性问题，但有一些事情可以使用更正，也许这些更改会纠正行为。

几点：

我的感觉是你应该把@Id列 Long 或 Integer 并保持一致。
您的 impl 有一些令人困惑的结构。为什么需要get() 和getTanya()？
在下面的示例中，我注释的是字段，而不是 getter。这似乎是 Spring 的偏好，尽管有 varying opinions。
根据您提供的代码，我无法判断您是否包含@Transactional。无论如何，您都可以这样标记readOnly。
（旁白）如果不添加任何细节，则无需指定 FetchType.LAZY 或 @Column 之类的默认值。只包含最基本的代码，这样下一个人就更容易阅读了。

除此之外，您还可以dump a stack trace 并查看线程挂在哪里。

通用 CRUD 接口：

public interface GenericDao<T> {

    T find(Long id);

    List<T> findAll();

    T update(T t);

    T save(T t);

    void delete(Long id);
}

谭雅道：

public interface TanyaDao extends GenericDao<Tanya> {

    //add any specific Tanya code
}

TanyaDAOImpl：

@Repository
@Transactional
public class TanyaDaoImpl implements TanyaDao {

    @Override
    @Transactional(readOnly = true, timeout = 10)
    public Tanya find(Integer id) {
        return (Tanya) getCurrentSession().get(Tanya.class, id);
    }

    @Override
    @Transactional(readOnly = true, timeout = 10)
    public List<Tanya> findAll() {
        Criteria criteria = getCurrentSession().createCriteria(Tanya.class); // this may be different depending on your version of Hibernate
        @SuppressWarnings("unchecked")
        List<Tanya> tanyas = criteria.list();
        return tanyas;
    }

    @Override
    public Tanya update(Tanya tanya) {
        try {
            getCurrentSession().update(tanya);
        }
        catch (NonUniqueObjectException ignored) {
            tanya = (Tanya) getCurrentSession().merge(tanya); //you may or may not need to do this part
        }
        return tanya;
    }

    @Override
    public Tanya save(Tanya tanya) {
        Serializable id = getCurrentSession().save(tanya);
        return (Tanya) getCurrentSession().get(Tanya.class, id);
    }

    @Override
    public void delete(Integer id) {
        Tanya tanya = find(id.intValue());
        getCurrentSession().delete(tanya);
    }

    @Autowired
    private SessionFactory sessionFactory;

    private Session getCurrentSession() {
        return sessionFactory.getCurrentSession();
    }
}

用户：

@Entity
@Table(name = "user")
public class User implements Serializable {

    @Id
    @Column(name = "no_dana")
    @GeneratedValue
    private Long id;

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "user")
    private Set<Tanya> tanya;

    @OneToMany(mappedBy = "user")
    private Set<Jawab> jawab;

    public Long getId() {

        return id;
    }

    public void setId(Long id) {

        this.id = id;
    }

    public Set<Tanya> getTanya() {

        return tanya;
    }

    public void setTanya(Set<Tanya> tanya) {

        this.tanya = tanya;
    }

    public Set<Jawab> getJawab() {

        return jawab;
    }

    public void setJawab(Set<Jawab> jawab) {

        this.jawab = jawab;
    }
}

贾瓦布：

@Entity
@Table(name = "jawab")
public class Jawab implements Serializable {

    @Id
    @GeneratedValue
    @Column(name = "id_jawab")
    private Long id;

    private String isi;

    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "no_dana")
    private User user;

    @ManyToOne
    @JoinColumn(name = "id_tanya")
    private Tanya tanya;

    public Long getId() {

        return id;
    }

    public void setId(Long id) {

        this.id = id;
    }

    public String getIsi() {

        return isi;
    }

    public void setIsi(String isi) {

        this.isi = isi;
    }

    public User getUser() {

        return user;
    }

    public void setUser(User user) {

        this.user = user;
    }

    public Tanya getTanya() {

        return tanya;
    }

    public void setTanya(Tanya tanya) {

        this.tanya = tanya;
    }

}

谭雅：

@Entity
@Table(name = "tanya")
public class Tanya implements Serializable {

    @Id
    @GeneratedValue
    @Column(name = "id_tanya")
    private Long id;

    private String isi;

    @ManyToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "no_dana")
    private User user;

    @OneToMany(mappedBy = "tanya")
    private Set<Jawab> jawab;

    public Long getId() {

        return id;
    }

    public void setId(Long id) {

        this.id = id;
    }

    public String getIsi() {

        return isi;
    }

    public void setIsi(String isi) {

        this.isi = isi;
    }

    public User getUser() {

        return user;
    }

    public void setUser(User user) {

        this.user = user;
    }

    public Set<Jawab> getJawab() {

        return jawab;
    }

    public void setJawab(Set<Jawab> jawab) {

        this.jawab = jawab;
    }

}

【讨论】：

我已经删除了所有的关系，但在输入搜索时仍然遇到同样的问题，真的不知道 :DD ~