Hibernate关联关系映射(双向篇)-MySQL-Tutorial-php.cn

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Hibernate关联关系映射(双向篇)

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Jun 07, 2016 pm 02:51 PM

hibernate 关系 Verein 映射

Hibernate关联关系可分为单向关联和双向关联两大类。单向关联可以分为一对一、一对多、多对一和多对多4种关联方式，而多向关联可以分为一对一、一对多和多对多3种关联方式。 Hibernate连接管理类HibernateUtil.Java public class HibernateUtil { private st

Hibernate关联关系可分为单向关联和双向关联两大类。单向关联可以分为一对一、一对多、多对一和多对多4种关联方式，而多向关联可以分为一对一、一对多和多对多3种关联方式。

Hibernate连接管理类HibernateUtil.Java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> HibernateUtil {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">static</span> SessionFactory sessionFactory;

    <span class="hljs-keyword">private</span> <span class="hljs-keyword">static</span> final ThreadLocal<Session> threadLocal = <span class="hljs-keyword">new</span> ThreadLocal<Session>();

    <span class="hljs-keyword">static</span>{
        <span class="hljs-keyword">try</span>{
            Configuration cfg = <span class="hljs-keyword">new</span> Configuration().configure();
            sessionFactory = cfg.buildSessionFactory();
        }<span class="hljs-keyword">catch</span>(Throwable ex){
            <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> ExceptionInInitializerError(ex);
        }
    }

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> SessionFactory <span class="hljs-title">getSessionFactory</span>(){
        <span class="hljs-keyword">return</span> sessionFactory;
    }

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> Session <span class="hljs-title">getSession</span>() throws HibernateException{
        Session session = (Session)threadLocal.<span class="hljs-keyword">get</span>();
        <span class="hljs-keyword">if</span>(session == <span class="hljs-keyword">null</span> || !session.isOpen()){
            session = (sessionFactory != <span class="hljs-keyword">null</span>)?sessionFactory.openSession():<span class="hljs-keyword">null</span>;
            threadLocal.<span class="hljs-keyword">set</span>(session);
        }

        <span class="hljs-keyword">return</span> session;
    }

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title">closeSession</span>() throws HibernateException{
        Session session = (Session)threadLocal.<span class="hljs-keyword">get</span>();
        threadLocal.<span class="hljs-keyword">set</span>(<span class="hljs-keyword">null</span>);
        <span class="hljs-keyword">if</span>(session != <span class="hljs-keyword">null</span>){
            session.close();
        }
    }

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title">shutdown</span>(){
        getSessionFactory().close();
    }

}</code>

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1.双向的一对一关联

（1）通过主键关联

通过主键关联的双向一对一映射，在需要一方的配置文件中将主键生成策略配置成foreign，即表示需要根据另一方的主键来生成自己的主键，而该实体本身不具有自己的主键生成策略。

示例：

实体类：

User.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> User {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> userid;
    <span class="hljs-keyword">private</span> String name;
    <span class="hljs-keyword">private</span> String password;
    <span class="hljs-keyword">private</span> Address address;

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getUserid</span>() {
        <span class="hljs-keyword">return</span> userid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUserid</span>(<span class="hljs-keyword">int</span> userid) {
        <span class="hljs-keyword">this</span>.userid = userid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getName</span>() {
        <span class="hljs-keyword">return</span> name;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setName</span>(String name) {
        <span class="hljs-keyword">this</span>.name = name;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getPassword</span>() {
        <span class="hljs-keyword">return</span> password;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setPassword</span>(String password) {
        <span class="hljs-keyword">this</span>.password = password;
    }
    <span class="hljs-keyword">public</span> Address <span class="hljs-title">getAddress</span>() {
        <span class="hljs-keyword">return</span> address;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddress</span>(Address address) {
        <span class="hljs-keyword">this</span>.address = address;
    }       
}</code>

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Address.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> Address {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> addressid;
    <span class="hljs-keyword">private</span> String addressinfo;
    <span class="hljs-keyword">private</span> User user;

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getAddressid</span>() {
        <span class="hljs-keyword">return</span> addressid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressid</span>(<span class="hljs-keyword">int</span> addressid) {
        <span class="hljs-keyword">this</span>.addressid = addressid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getAddressinfo</span>() {
        <span class="hljs-keyword">return</span> addressinfo;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressinfo</span>(String addressinfo) {
        <span class="hljs-keyword">this</span>.addressinfo = addressinfo;
    }
    <span class="hljs-keyword">public</span> User <span class="hljs-title">getUser</span>() {
        <span class="hljs-keyword">return</span> user;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUser</span>(User user) {
        <span class="hljs-keyword">this</span>.user = user;
    }   

}</code>

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表结构：

User表

这里写图片描述

Address表

这里写图片描述

配置文件：

Use.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.User"</span> table=<span class="hljs-string">"user"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"userid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>/>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"name"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"name"</span>>
        </<span class="hljs-keyword">property</span>>
        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"password"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"password"</span>>
        </<span class="hljs-keyword">property</span>>

        <one-<span class="hljs-keyword">to</span>-one <span class="hljs-property">name</span>=<span class="hljs-string">"address"</span> <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.Address"</span> cascade=<span class="hljs-string">"all"</span>/>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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Address.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.Address"</span> table=<span class="hljs-string">"address"<span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"addressid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"foreign"</span>>
                <param <span class="hljs-property">name</span>=<span class="hljs-string">"property"</span>>user</param>
            </generator>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressinfo"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"addressinfo"</span>>
        </<span class="hljs-keyword">property</span>>

        <one-<span class="hljs-keyword">to</span>-one <span class="hljs-property">name</span>=<span class="hljs-string">"user"</span> <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.User"</span> constrained=<span class="hljs-string">"true"</span>/>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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测试类Test.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> Test {
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title">main</span>(String[] args){
        Session session = HibernateUtil.getSession();
        Transaction tx = session.beginTransaction();

        User u = <span class="hljs-keyword">new</span> User();
        u.setName(<span class="hljs-string">"sbw"</span>);
        u.setPassword(<span class="hljs-string">"123"</span>);       


        Address a = <span class="hljs-keyword">new</span> Address();
        a.setAddressinfo(<span class="hljs-string">"heu"</span>);

        a.setUser(u);
        u.setAddress(a);


        session.save(u);
        session.save(a);
        tx.commit();

        HibernateUtil.closeSession();

    }
}</code>

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测试结果：

这里写图片描述

（2）通过外键关联

通过外键关联的双向一对一映射，外键可以放在任意一方。在存放外键一方的映射文件中，需要添加many-to-one元素，并为该元素添加unique=“true”属性。而另一方的配置文件中要添加one-to-one元素，并使用其name属性来指定关联属性名。此时，存放外键的一方对应的数据表为从表，而另一方对应的数据表变为主表。

实体类与通过主键关联相同。

表结构：

user表

这里写图片描述

address表

这里写图片描述

配置文件：

User.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.User"</span> table=<span class="hljs-string">"user"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"userid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>/>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"name"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"name"</span>>
        </<span class="hljs-keyword">property</span>>
        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"password"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"password"</span>>
        </<span class="hljs-keyword">property</span>>

        <one-<span class="hljs-keyword">to</span>-one <span class="hljs-property">name</span>=<span class="hljs-string">"address"</span> cascade=<span class="hljs-string">"all"</span>/>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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Address.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.Address"</span> table=<span class="hljs-string">"address"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"addressid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>>
            </generator>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressinfo"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"addressinfo"</span>>
        </<span class="hljs-keyword">property</span>>

        <many-<span class="hljs-keyword">to</span>-one <span class="hljs-property">name</span>=<span class="hljs-string">"user"</span> <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.User"</span> unique=<span class="hljs-string">"true"</span>>
            <column <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span>/>
        </many-<span class="hljs-keyword">to</span>-one>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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测试类与通过主键关联一样

测试结果：

这里写图片描述

2.双向的一对多关联(与双向多对一完全相同)

双向的一对多关联在“多”的一方要增加新属性以引用关联实体，在“一”的一方则增加集合属性，该集合中包含“多”的一方的关联实体。

实体类：

User.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> User {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> userid;
    <span class="hljs-keyword">private</span> String name;
    <span class="hljs-keyword">private</span> String password;
    <span class="hljs-keyword">private</span> Set<Address> address = <span class="hljs-keyword">new</span> HashSet<Address>();

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getUserid</span>() {
        <span class="hljs-keyword">return</span> userid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUserid</span>(<span class="hljs-keyword">int</span> userid) {
        <span class="hljs-keyword">this</span>.userid = userid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getName</span>() {
        <span class="hljs-keyword">return</span> name;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setName</span>(String name) {
        <span class="hljs-keyword">this</span>.name = name;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getPassword</span>() {
        <span class="hljs-keyword">return</span> password;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setPassword</span>(String password) {
        <span class="hljs-keyword">this</span>.password = password;
    }
    <span class="hljs-keyword">public</span> Set<Address> <span class="hljs-title">getAddress</span>() {
        <span class="hljs-keyword">return</span> address;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddress</span>(Set<Address> address) {
        <span class="hljs-keyword">this</span>.address = address;
    }       
}</code>

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Address.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> Address {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> addressid;
    <span class="hljs-keyword">private</span> String addressinfo;
    <span class="hljs-keyword">private</span> User user;

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getAddressid</span>() {
        <span class="hljs-keyword">return</span> addressid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressid</span>(<span class="hljs-keyword">int</span> addressid) {
        <span class="hljs-keyword">this</span>.addressid = addressid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getAddressinfo</span>() {
        <span class="hljs-keyword">return</span> addressinfo;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressinfo</span>(String addressinfo) {
        <span class="hljs-keyword">this</span>.addressinfo = addressinfo;
    }
    <span class="hljs-keyword">public</span> User <span class="hljs-title">getUser</span>() {
        <span class="hljs-keyword">return</span> user;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUser</span>(User user) {
        <span class="hljs-keyword">this</span>.user = user;
    }   

}</code>

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表结构：

user表

这里写图片描述

address表

这里写图片描述

配置文件

User.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.User"</span> table=<span class="hljs-string">"user"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"userid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>/>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"name"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"name"</span>>
        </<span class="hljs-keyword">property</span>>
        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"password"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"password"</span>>
        </<span class="hljs-keyword">property</span>>

        <<span class="hljs-keyword">set</span> <span class="hljs-property">name</span>=<span class="hljs-string">"address"</span> table=<span class="hljs-string">"address"</span> inverse=<span class="hljs-string">"true"</span> lazy=<span class="hljs-string">"true"</span>>
            <key>
                <column <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span>/>
            </key>

            <one-<span class="hljs-keyword">to</span>-many <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.Address"</span>/>
        </<span class="hljs-keyword">set</span>>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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Address.hbm.xml

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.Address"</span> table=<span class="hljs-string">"address"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"addressid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>>
            </generator>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"addressinfo"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"addressinfo"</span>>
        </<span class="hljs-keyword">property</span>>

        <many-<span class="hljs-keyword">to</span>-one <span class="hljs-property">name</span>=<span class="hljs-string">"user"</span> <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.User"</span> unique=<span class="hljs-string">"true"</span>>
            <column <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span>/>
        </many-<span class="hljs-keyword">to</span>-one>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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测试类Test.java

<code class=" hljs avrasm">public class Test {
    public static void main(String[] args){
        Session session = HibernateUtil<span class="hljs-preprocessor">.getSession</span>()<span class="hljs-comment">;</span>
        Transaction tx = session<span class="hljs-preprocessor">.beginTransaction</span>()<span class="hljs-comment">;</span>

        User u = new User()<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.setName</span>(<span class="hljs-string">"sbw"</span>)<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.setPassword</span>(<span class="hljs-string">"123"</span>)<span class="hljs-comment">;       </span>


        Address a = new Address()<span class="hljs-comment">;</span>
        a<span class="hljs-preprocessor">.setAddressinfo</span>(<span class="hljs-string">"heu"</span>)<span class="hljs-comment">;</span>
        Address a1 = new Address()<span class="hljs-comment">;</span>
        a<span class="hljs-preprocessor">.setAddressinfo</span>(<span class="hljs-string">"hrb"</span>)<span class="hljs-comment">;</span>

        a<span class="hljs-preprocessor">.setUser</span>(u)<span class="hljs-comment">;</span>
        a1<span class="hljs-preprocessor">.setUser</span>(u)<span class="hljs-comment">;</span>

        u<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a)<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a1)<span class="hljs-comment">;</span>

        session<span class="hljs-preprocessor">.save</span>(a)<span class="hljs-comment">;</span>
        session<span class="hljs-preprocessor">.save</span>(a1)<span class="hljs-comment">;</span>
        session<span class="hljs-preprocessor">.save</span>(u)<span class="hljs-comment">;</span>
        tx<span class="hljs-preprocessor">.commit</span>()<span class="hljs-comment">;</span>

        HibernateUtil<span class="hljs-preprocessor">.closeSession</span>()<span class="hljs-comment">;</span>

    }
}</code>

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测试结果：

这里写图片描述

3.双向的多对多关联

在双向的多对多关联中，两端都要添加Set集合属性。要实现双向的多对多关联，必须使用中间表来实现两个实体间的关联关系。

示例：

实体类

User.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> User {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> userid;
    <span class="hljs-keyword">private</span> String name;
    <span class="hljs-keyword">private</span> String password;
    <span class="hljs-keyword">private</span> Set<Address> address = <span class="hljs-keyword">new</span> HashSet<Address>();

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getUserid</span>() {
        <span class="hljs-keyword">return</span> userid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUserid</span>(<span class="hljs-keyword">int</span> userid) {
        <span class="hljs-keyword">this</span>.userid = userid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getName</span>() {
        <span class="hljs-keyword">return</span> name;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setName</span>(String name) {
        <span class="hljs-keyword">this</span>.name = name;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getPassword</span>() {
        <span class="hljs-keyword">return</span> password;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setPassword</span>(String password) {
        <span class="hljs-keyword">this</span>.password = password;
    }
    <span class="hljs-keyword">public</span> Set<Address> <span class="hljs-title">getAddress</span>() {
        <span class="hljs-keyword">return</span> address;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddress</span>(Set<Address> address) {
        <span class="hljs-keyword">this</span>.address = address;
    }       
}</code>

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Address.java

<code class=" hljs cs"><span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> Address {
    <span class="hljs-keyword">private</span> <span class="hljs-keyword">int</span> addressid;
    <span class="hljs-keyword">private</span> String addressinfo;
    <span class="hljs-keyword">private</span> Set<User> user = <span class="hljs-keyword">new</span> HashSet<User>();

    <span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">getAddressid</span>() {
        <span class="hljs-keyword">return</span> addressid;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressid</span>(<span class="hljs-keyword">int</span> addressid) {
        <span class="hljs-keyword">this</span>.addressid = addressid;
    }
    <span class="hljs-keyword">public</span> String <span class="hljs-title">getAddressinfo</span>() {
        <span class="hljs-keyword">return</span> addressinfo;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setAddressinfo</span>(String addressinfo) {
        <span class="hljs-keyword">this</span>.addressinfo = addressinfo;
    }
    <span class="hljs-keyword">public</span> Set<User> <span class="hljs-title">getUser</span>() {
        <span class="hljs-keyword">return</span> user;
    }
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">setUser</span>(Set<User> user) {
        <span class="hljs-keyword">this</span>.user = user;
    }   

}</code>

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表结构：

user表

这里写图片描述

address表

这里写图片描述

user_address表

这里写图片描述

配置文件

User.hbm.xml:

<code class=" hljs applescript"><hibernate-mapping>
    <<span class="hljs-type">class</span> <span class="hljs-property">name</span>=<span class="hljs-string">"com.entity.User"</span> table=<span class="hljs-string">"user"</span>>
        <<span class="hljs-property">id</span> <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span> type=<span class="hljs-string">"java.lang.Integer"</span> column=<span class="hljs-string">"userid"</span>>
            <generator <span class="hljs-type">class</span>=<span class="hljs-string">"identity"</span>/>
        </<span class="hljs-property">id</span>>

        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"name"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"name"</span>>
        </<span class="hljs-keyword">property</span>>
        <<span class="hljs-keyword">property</span> <span class="hljs-property">name</span>=<span class="hljs-string">"password"</span> type=<span class="hljs-string">"java.lang.String"</span> column=<span class="hljs-string">"password"</span>>
        </<span class="hljs-keyword">property</span>>

        <<span class="hljs-keyword">set</span> <span class="hljs-property">name</span>=<span class="hljs-string">"address"</span> table=<span class="hljs-string">"user_address"</span> inverse=<span class="hljs-string">"true"</span>>
            <key>
                <column <span class="hljs-property">name</span>=<span class="hljs-string">"userid"</span>/>
            </key>

            <many-<span class="hljs-keyword">to</span>-many <span class="hljs-type">class</span>=<span class="hljs-string">"com.entity.Address"</span> column=<span class="hljs-string">"addressid"</span>/>
        </<span class="hljs-keyword">set</span>>

    </<span class="hljs-type">class</span>>
</hibernate-mapping></code>

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Address.hbm.xml

<code class=" hljs xml"><span class="hljs-tag"><<span class="hljs-title">hibernate-mapping</span>></span>
    <span class="hljs-tag"><<span class="hljs-title">class</span> <span class="hljs-attribute">name</span>=<span class="hljs-value">"com.entity.Address"</span> <span class="hljs-attribute">table</span>=<span class="hljs-value">"address"</span>></span>
        <span class="hljs-tag"><<span class="hljs-title">id</span> <span class="hljs-attribute">name</span>=<span class="hljs-value">"addressid"</span> <span class="hljs-attribute">type</span>=<span class="hljs-value">"java.lang.Integer"</span> <span class="hljs-attribute">column</span>=<span class="hljs-value">"addressid"</span>></span>
            <span class="hljs-tag"><<span class="hljs-title">generator</span> <span class="hljs-attribute">class</span>=<span class="hljs-value">"identity"</span>></span>
            <span class="hljs-tag"></<span class="hljs-title">generator</span>></span>
        <span class="hljs-tag"></<span class="hljs-title">id</span>></span>

        <span class="hljs-tag"><<span class="hljs-title">property</span> <span class="hljs-attribute">name</span>=<span class="hljs-value">"addressinfo"</span> <span class="hljs-attribute">type</span>=<span class="hljs-value">"java.lang.String"</span> <span class="hljs-attribute">column</span>=<span class="hljs-value">"addressinfo"</span>></span>
        <span class="hljs-tag"></<span class="hljs-title">property</span>></span>

        <span class="hljs-tag"><<span class="hljs-title">set</span> <span class="hljs-attribute">name</span>=<span class="hljs-value">"user"</span> <span class="hljs-attribute">table</span>=<span class="hljs-value">"user_address"</span>></span>
            <span class="hljs-tag"><<span class="hljs-title">key</span>></span>
                <span class="hljs-tag"><<span class="hljs-title">column</span> <span class="hljs-attribute">name</span>=<span class="hljs-value">"addressid"</span>/></span>
            <span class="hljs-tag"></<span class="hljs-title">key</span>></span>

            <span class="hljs-tag"><<span class="hljs-title">many-to-many</span> <span class="hljs-attribute">class</span>=<span class="hljs-value">"com.entity.User"</span> <span class="hljs-attribute">column</span>=<span class="hljs-value">"userid"</span>/></span>
        <span class="hljs-tag"></<span class="hljs-title">set</span>></span>

    <span class="hljs-tag"></<span class="hljs-title">class</span>></span>
<span class="hljs-tag"></<span class="hljs-title">hibernate-mapping</span>></span></code>

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测试类Test.java

<code class=" hljs avrasm">public class Test {
    public static void main(String[] args){
        Session session = HibernateUtil<span class="hljs-preprocessor">.getSession</span>()<span class="hljs-comment">;</span>
        Transaction tx = session<span class="hljs-preprocessor">.beginTransaction</span>()<span class="hljs-comment">;</span>

        User u = new User()<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.setName</span>(<span class="hljs-string">"sbw"</span>)<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.setPassword</span>(<span class="hljs-string">"123"</span>)<span class="hljs-comment">;       </span>

        User u1 = new User()<span class="hljs-comment">;</span>
        u1<span class="hljs-preprocessor">.setName</span>(<span class="hljs-string">"gaoya"</span>)<span class="hljs-comment">;</span>
        u1<span class="hljs-preprocessor">.setPassword</span>(<span class="hljs-string">"456"</span>)<span class="hljs-comment">;</span>

        Address a = new Address()<span class="hljs-comment">;</span>
        a<span class="hljs-preprocessor">.setAddressinfo</span>(<span class="hljs-string">"heu"</span>)<span class="hljs-comment">;</span>
        Address a1 = new Address()<span class="hljs-comment">;</span>
        a1<span class="hljs-preprocessor">.setAddressinfo</span>(<span class="hljs-string">"hrb"</span>)<span class="hljs-comment">;</span>

        a<span class="hljs-preprocessor">.getUser</span>()<span class="hljs-preprocessor">.add</span>(u)<span class="hljs-comment">;</span>
        a<span class="hljs-preprocessor">.getUser</span>()<span class="hljs-preprocessor">.add</span>(u1)<span class="hljs-comment">;</span>
        a1<span class="hljs-preprocessor">.getUser</span>()<span class="hljs-preprocessor">.add</span>(u)<span class="hljs-comment">;</span>
        a1<span class="hljs-preprocessor">.getUser</span>()<span class="hljs-preprocessor">.add</span>(u1)<span class="hljs-comment">;</span>

        u<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a)<span class="hljs-comment">;</span>
        u<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a1)<span class="hljs-comment">;</span>
        u1<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a)<span class="hljs-comment">;</span>
        u1<span class="hljs-preprocessor">.getAddress</span>()<span class="hljs-preprocessor">.add</span>(a1)<span class="hljs-comment">;</span>

        session<span class="hljs-preprocessor">.save</span>(a)<span class="hljs-comment">;</span>
        session<span class="hljs-preprocessor">.save</span>(a1)<span class="hljs-comment">;</span>
        session<span class="hljs-preprocessor">.save</span>(u)<span class="hljs-comment">;</span>
        session<span class="hljs-preprocessor">.save</span>(u1)<span class="hljs-comment">;</span>
        tx<span class="hljs-preprocessor">.commit</span>()<span class="hljs-comment">;</span>

        HibernateUtil<span class="hljs-preprocessor">.closeSession</span>()<span class="hljs-comment">;</span>

    }
}</code>

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测试结果：

这里写图片描述

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