Question

<<>Summary

I m trying to run a Java web application JPA 2.0 example. The example application was written to run in Glassfish, using EclipseLink as JPA provider. I would like to convert it to run in TomEE with OpenJPA as the JPA provider, but I can t any detailed tutorials for getting up and running with OpenJPA.

<><>Problem>

页: 1 更具体地说,<代码>persistence.xml 注

Entity classes. Are these necessary?
The desired JPA provider. Will the container default to something?
The JDBC driver. How do I specify an "in-memory" DB (just for initial testing purposes)?

此外:

How are the DDL generation properties expressed in OpenJPA? I wasn t able to find them the OpenJPA User Guide.

<> 详情>

下面是EclipseLinkpersistence.xml:

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0"
    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_2_0.xsd">
    <persistence-unit name="order" transaction-type="JTA">
        <jta-data-source>jdbc/__default</jta-data-source>
        <properties>
            <property name="eclipselink.ddl-generation" value="drop-and-create-tables" />
            <property name="eclipselink.ddl-generation.output-mode"
                value="both" />
        </properties>
    </persistence-unit>
</persistence>

我有以下<密码>:

order.entity.LineItem
order.entity.LineItemKey
order.entity.Order
order.entity.Part
order.entity.PartKey
order.entity.Vendor
order.entity.VendorPart

<<><><><><>>>>><><><>>>>>

Does anyone know what the equivalent persistence.xml would look like for OpenJPA?
Alternatively, if anyone could point me to an OpenJPA tutorial that covers these issues that would be just as good

Answer 1

如果添加<条码>开放式jpa.jdbc.SynchronizeMappings 财产,如下文所示,开放式JPA将把所有表格、所有主要钥匙和所有外国钥匙自动化,与你的物体相匹配。

<property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema(ForeignKeys=true)"/>

或者,你可以在TomEE中使用EclipseLink, 仅将EclipseLink jars添入<CATALINA_HOME>/lib/。

http://openejb.apache.org/common-persistenceprovider-properties.html。共同财产:

Answer 2

Foreign key constraints

下一行不产生外国钥匙:

<property name="openjpa.jdbc.SynchronizeMappings" 
          value="buildSchema(ForeignKeys=true)"/>

只制作图表,删除数据库的内容。

但是,如果你想要创造外国钥匙,则使用以下路线:

<property name="openjpa.jdbc.SynchronizeMappings" 
          value="buildSchema(foreignKeys=true,schemaAction= dropDB,add )"/>
<property name="openjpa.jdbc.SchemaFactory" 
          value="native(foreignKeys=true)" />
<property name="openjpa.jdbc.MappingDefaults" 
          value="ForeignKeyDeleteAction=restrict, JoinForeignKeyDeleteAction=restrict"/>

See generated SQL

另一种方式是,如果你想看到“结构”的产出:

<property name="openjpa.Log" 
          value="DefaultLevel=TRACE,SQL=TRACE" />

。为了了解托梅列公司的生成产出,你需要修改文档中的标识水平:loggin.properties, openjpa.level = FINEST 。

See more in 。

Foreign key constraints

See generated SQL

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