使用jpa和hibernate在orm.xml中定义命名查询

Question

我正在尝试将我的命名查询放在我的orm.xml中(使用persistence.xml放入META-INF)但是我的orm.xml似乎被hibernate/jpa忽略了.

当我尝试使用em.createNamedQuery("myQuery")创建我的命名查询时,它返回它无法找到此查询.

我使用注释,我想在orm.xml中外化我的命名查询(仅限于此).

这是我的persistence.xml:

<?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="default" transaction-type="RESOURCE_LOCAL">
    <mapping-file>META-INF/orm.xml</mapping-file>

    <class>com.mysite.Account</class>

    <properties>
        <property name="hibernate.cache.provider_class" value="net.sf.ehcache.hibernate.EhCacheProvider" />
        <property name="hibernate.cache.use_query_cache" value="true" />
        <property name="hibernate.cache.use_second_level_cache" value="true" />
        <property name="hibernate.show_sql" value="true" />
        <property name="hibernate.format_sql" value="true" />
        <property name="use_sql_comments" value="false" />
        <property name="hibernate.dialect" value="org.hibernate.dialect.MYSQLDialect" />
        <property name="hibernate.c3p0.min_size" value="5" />
        <property name="hibernate.c3p0.max_size" value="20" />
        <property name="hibernate.c3p0.timeout" value="300" />
        <property name="hibernate.c3p0.max_statements" value="50" />
        <property name="hibernate.c3p0.idle_test_period" value="3000" />

        <property name="hibernate.search.default.directory_provider" value="org.hibernate.search.store.FSDirectoryProvider" />
    </properties>

</persistence-unit>

</persistence>

这是我的orm.xml

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_1_0.xsd" version="1.0">

<package>com.mysite</package>

<entity class="Account">
    <sql-result-set-mapping name="nicknames">
        <column-result name="nickname" />
    </sql-result-set-mapping>
    <table name="Account" />
    <named-native-query name="myQuery" result-set-mapping="nicknames">
        <query><![CDATA[select a.nickname from Account a]]>
    </query>
    </named-native-query>
</entity>
</entity-mappings>

我做错了什么？为什么我的orm.xml被忽略了？

谢谢

Answer 1

好的,我终于明白了!

我将我的orm.xml保存在META-INF目录中.当我将此文件移动到我的域名对象的包中时(如我的示例:com.mysite),orm.xml不会被忽略并且全部运行.

我还需要更改mapping-file(persistence.xml)中的路径:com/mysite/orm.xml

Answer 2

你的 orm.xml 有一个小错误，它破坏了整个事情。关键是元素声明的顺序应该符合各自的 XML 模式（特别是http://java.sun.com/xml/ns/persistence/orm_1_0.xsd）。通过使用支持 xml 模式的验证器运行 xml 代码，这很容易检查。以下是您的 orm.xml 的更正版本，它必须具有魅力。

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:schemaLocation="
                     http://java.sun.com/xml/ns/persistence/orm
                     http://java.sun.com/xml/ns/persistence/orm_1_0.xsd"
                 version="1.0">

    <package>com.mysite</package>

    <entity class="Account">
        <table name="Account" />
        <named-native-query name="myQuery" result-set-mapping="nicknames">
            <query><![CDATA[
            select a.nickname from Account a
            ]]></query>
        </named-native-query>
        <sql-result-set-mapping name="nicknames">
            <column-result name="nickname" />
        </sql-result-set-mapping>
    </entity>
</entity-mappings>