Hibernate learning notes 2

Hibernate mapping

One to many, one to one, many to many

One to many mapping

Common attributes of the set element

<span style="color: #0000ff;">import<span style="color: #000000;"> org.hibernate.Session;

<span style="color: #0000ff;">import<span style="color: #000000;"> org.hibernate.SessionFactory;

<span style="color: #0000ff;">import<span style="color: #000000;"> org.hibernate.boot.registry.StandardServiceRegistry;

<span style="color: #0000ff;">import<span style="color: #000000;"> org.hibernate.boot.registry.StandardServiceRegistryBuilder;

<span style="color: #0000ff;">import<span style="color: #000000;"> org.hibernate.cfg.Configuration;

<span style="color: #0000ff;">public <span style="color: #0000ff;">class<span style="color: #000000;"> HibernateUtil {

<span style="color: #0000ff;">private <span style="color: #0000ff;">static<span style="color: #000000;"> SessionFactory sessionFactory;

<span style="color: #0000ff;">private <span style="color: #0000ff;">static<span style="color: #000000;"> Session session;
</span><span style="color: #0000ff;"&gt;static</span><span style="color: #000000;"&gt; {
    </span><span style="color: #008000;"&gt;//</span><span style="color: #008000;"&gt; 创建Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>uration对象  读取hibernate.cfg.cml<a href="https://www.jb51.cc/tag/wenjian/" target="_blank" class="keywords">文件</a>。完成初始化</span>
    Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>uration con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a> = <span style="color: #0000ff;"&gt;new</span><span style="color: #000000;"&gt; Con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>uration().con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>ure();
    StandardServiceRegistryBuilder ssrb </span>= <span style="color: #0000ff;"&gt;new</span><span style="color: #000000;"&gt; StandardServiceRegistryBuilder().
            applySettings(con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>.getProperties());
    StandardServiceRegistry ssr </span>=<span style="color: #000000;"&gt; ssrb.build();
    sessionFactory </span>=<span style="color: #000000;"&gt; con<a href="https://www.jb51.cc/tag/fig/" target="_blank" class="keywords">fig</a>.buildSessionFactory(ssr);
}

</span><span style="color: #008000;"&gt;//</span><span style="color: #008000;"&gt; <a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>SessionFactory对象</span>
<span style="color: #0000ff;"&gt;public</span> <span style="color: #0000ff;"&gt;static</span><span style="color: #000000;"&gt; SessionFactory getSessionFactory() {
    </span><span style="color: #0000ff;"&gt;return</span><span style="color: #000000;"&gt; sessionFactory;
}

</span><span style="color: #008000;"&gt;//</span><span style="color: #008000;"&gt; <a href="https://www.jb51.cc/tag/huoqu/" target="_blank" class="keywords">获取</a>Session</span>
<span style="color: #0000ff;"&gt;public</span> <span style="color: #0000ff;"&gt;static</span><span style="color: #000000;"&gt; Session getSession() {
    session </span>=<span style="color: #000000;"&gt; sessionFactory.openSession();
    </span><span style="color: #0000ff;"&gt;return</span><span style="color: #000000;"&gt; session;
}

</span><span style="color: #008000;"&gt;//</span><span style="color: #008000;"&gt; <a href="https://www.jb51.cc/tag/guanbi/" target="_blank" class="keywords">关闭</a>Session</span>
<span style="color: #0000ff;"&gt;public</span> <span style="color: #0000ff;"&gt;static</span> <span style="color: #0000ff;"&gt;void</span><span style="color: #000000;"&gt; closeSession(Session session) {
    </span><span style="color: #0000ff;"&gt;if</span> (session != <span style="color: #0000ff;"&gt;null</span><span style="color: #000000;"&gt;) {
        session.close();
    }
}
}