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最近開始嘗試hibernate annotations，終于成功的將手上一個(gè)小應(yīng)用轉(zhuǎn)為annotations
1、spring orm support 與原來(lái)使用LocalSessionFactoryBean相比，變動(dòng)不大（AnnotationSessionFactoryBean本來(lái)就是從LocalSessionFactoryBean類繼承過(guò)來(lái)的嘛） <!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>--> 1 <bean
2、id的配置2 id="sessionFactory" 3 class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean" 4 parent="AbstractSessionFactory"> 5 <property name="annotatedClasses"> 6 <list> 7 <value>xxx.xxx.xxx.domain.Accountvalue> 8 list> 9 property> 10 bean> 11 <bean 12 id="AbstractSessionFactory" 13 class="org.springframework.orm.hibernate3.LocalSessionFactoryBean" 14 abstract="true"> 15 <property 16 name="dataSource" 17 ref="DataSource" /> 18 <property name="hibernateProperties"> 19 <props> 20 <prop key="hibernate.dialect">${hibernate.dialect}prop> 21 <prop key="hibernate.show_sql">${hibernate.show_sql}prop> 22 <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}prop> 23 <prop key="hibernate.cache.use_query_cache">${hibernate.cache.use_query_cache}prop> 24 <prop key="hibernate.cache.provider_class">${hibernate.cache.provider_class}prop> 25 props> 26 property> 27 <property 28 name="lobHandler" 29 ref="DefaultLobHandler" /> 30 bean> 非常簡(jiǎn)單，在id的getter上面加個(gè)“@Id”就可以了。此時(shí)采用的id策略是javax.persistence.GenerationType.AUTO，也可以再加上“@GeneratedValue(generator =GenerationType.IDENTITY|GenerationType.SEQUENCE|GenerationType.TABLE)”換成其它策略。 我的應(yīng)用采用的是hibernate的uuid策略，就不得不在這兒使用hibernate的擴(kuò)展了 <!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>--> @Id
@Column(length = 32) @GeneratedValue(generator = "system-uuid") @GenericGenerator(name = "system-uuid", strategy = "uuid") 3、級(jí)聯(lián)策略 在ejb3-persistence.jar中只定義了ALL、MERGE、PERSIST、REFRESH、REMOVE，比較惡心的就是，刪除對(duì)象的時(shí)候，并不會(huì)級(jí)聯(lián)刪除關(guān)聯(lián)對(duì)象，而是用update xx set parent_id=null where parent_id=?這類語(yǔ)句把關(guān)系干掉了事。不得已，在這兒用了hibernate的DELETE_ORPHAN。 <!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>--> @OneToMany(targetEntity = Attachment.class)
4、CACHE@Cascade(value = {org.hibernate.annotations.CascadeType.DELETE_ORPHAN, org.hibernate.annotations.CascadeType.ALL}) @JoinColumn(name = "info_id") ejb3-persistence.jar里面沒(méi)有找到cache的配置，繼續(xù)請(qǐng)出hibernate來(lái)干活 <!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>-->import org.hibernate.annotations.Cache;
5、自定義字段類型import org.hibernate.annotations.CacheConcurrencyStrategy; @Entity @Table(name = "T_INFO") @Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE) 我的POJO中有一個(gè)private String content;的屬性，按ejb3配成@Lob后，被處理成了text類型，text 64k的存儲(chǔ)容量還是比較可憐了。 <!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>--> @Lob
@Column(columnDefinition = "LongText") |
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