Persistence.xml 配置说明

3. Persistence.xml 配置说明 <?xml version="1.0" encoding="UTF-8"?> <persistence version="1.0" xmlns:persistence="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence persistence_1_0.xsd "> <!--      Name属性用于定义持久化单元的名字 (name必选,空值也合法);      transaction-type 指定事务类型(可选) --> <persistence-unit name="unitName" transaction-type="JTA">    <!-- 描述信息.(可选) -->    <description> </description>    <!-- javax.persistence.PersistenceProvider接口的一个实现类(可选) -->    <provider>   </provider>    <!-- Jta-data-source和 non-jta-data-source用于分别指定持久化提供商使用的JTA和/或non-JTA数据源的全局JNDI名称(可选) -->    <jta-data-source>java:/MySqlDS</jta-data-source>    <non-jta-data-source> </non-jta-data-source>    <!-- 声明orm.xml所在位置.(可选) -->    <mapping-file>product.xml</mapping-file>    <!-- 以包含persistence.xml的jar文件为基准的相对路径,添加额外的jar文件.(可选) -->    <jar-file>../lib/model.jar</jar-file>    <!-- 显式列出实体类,在Java SE 环境中应该显式列出.(可选) -->    <class>com.domain.User</class>    <class>com.domain.Product</class>    <!-- 声明是否扫描jar文件中标注了@Enity类加入到上下文.若不扫描,则如下:(可选) -->    <exclude-unlisted-classes/>    <!--   厂商专有属性(可选)   -->    <properties>     <!-- hibernate.hbm2ddl.auto= create-drop / create / update -->     <property name="hibernate.hbm2ddl.auto" value="update" />     <property name="hibernate.show_sql" value="true" />    </properties> </persistence-unit> </persistence> persistence.xml 2008-02-13 21:42 <?xml version="1.0" encoding="UTF-8"?> <persistence xmlns=" http://java.sun.com/xml/ns/persistence"     xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance"     xsi:schemaLocation=" http://java.sun.com/xml/ns/persistence     http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0">         <!--     persistence-unit name="EjbXmlMappingsPU" // 持久化单元名     transaction-type="JTA(default)/RESOURCE_LOCAL" // 事务类型     --> <persistence-unit name="EjbXmlMappingsPU" transaction-type="JTA">    <description></description> <!-- 描述 -->    <provider>oracle.toplink.essentials.PersistenceProvider</provider> <!-- 指定一个持久化提供者 -->    <jta-data-source>jdbc/MyDataSource</jta-data-source> <!-- 指定JTA数据源 -->    <non-jta-data-source>jdbc/NonTxMyDataSource</non-jta-data-source> <!-- 指定非JTA数据源 -->    <mapping-file>META-INF/my_queries.xml</mapping-file> <!-- 指定映射文件 -->    <mapping-file>META-INF/my_entities.xml</mapping-file>    <jar-file>my/my-classes.jar</jar-file> <!-- 指定托管类的附加JAR -->    <class>myclass1</class> <!-- 明确列出的类 -->    <class>myclass2</class>    <exclude-unlisted-classes/> <!-- 使本地类不能被加到持久化单元中 -->    <properties> <!-- 使用提供者属性 -->     <property name="toplink.logging.level" value="FINE"/>     <property name="toplink.cache.size.dafault" value="500"/>    </properties> </persistence-unit> </persistence>