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>
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>
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>
表结构：
User表
Address表
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>
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>
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>
测试结果：
（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
address表
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>
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>
测试类与通过主键关联一样
测试结果：
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>
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>
表结构：
user表
address表
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>
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>
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>
测试结果：
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>
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>
表结构：
user表
address表
user_address表
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>
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>
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>
测试结果：
성명
본 글의 내용은 네티즌들의 자발적인 기여로 작성되었으며, 저작권은 원저작자에게 있습니다. 본 사이트는 이에 상응하는 법적 책임을 지지 않습니다. 표절이나 침해가 의심되는 콘텐츠를 발견한 경우 admin@php.cn으로 문의하세요.
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