卡拉夫和持久性單元：缺少依賴關係：JpaTemplate

Question

我正在爭取安裝JPA並在Karaf 4.0.8容器上啓動持久性單元。我已經安裝：

feature:install webconsole 
feature:repo-add mvn:org.apache.aries.jpa/jpa-features/2.5.0/xml/features 
feature:install jpa/2.5.0 
feature:install transaction-api/1.2.0 
feature:install transaction 
feature:install eclipselink 

我與持久性單元捆綁開始，但它並沒有出口任何服務。使用它和進口的JpaTemplate束無法導入服務：

<reference id="jpaTemplate" interface="org.apache.aries.jpa.template.JpaTemplate" filter="(osgi.unit.name=officialUnit)" /> 

應該從我的持久性bundle導出，但事實並非如此。 'diag'顯示持久性捆綁包沒有問題。

如何調試持久單元未正確啓動的原因？

我的persistence.xml看起來像這樣：

<?xml version="1.0" encoding="UTF-8"?> 
<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" 
    version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"> 

    <persistence-unit name="officialUnit" transaction-type="JTA"> 
     <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider> 

     <!-- Only used when transaction-type=JTA --> 
     <jta-data-source>osgi:service/javax.sql.DataSource/(osgi.jndi.service.name=demo-db)</jta-data-source> 

     <!-- Only used when transaction-type=RESOURCE_LOCAL --> 
     <non-jta-data-source>osgi:service/javax.sql.DataSource/(osgi.jndi.service.name=demo-db)</non-jta-data-source> 

     <class>example.entity.SomeEntity</class>  

     <exclude-unlisted-classes>true</exclude-unlisted-classes> 
     <properties> 
      <property name="eclipselink.ddl-generation" value="none" /> 
      <property name="eclipselink.ddl-generation.output-mode" value="sql-script" /> 
     </properties> 

    </persistence-unit> 
</persistence> 

配置文件etc/org.ops4j.datasource-sqlitetest.cfg：

osgi.jdbc.driver.name=sqlite 
url=jdbc:sqlite:D:/data/db/demo.db 
dataSourceName=demo-db 

和持久性捆綁的MANIFEST.MF：

Manifest-Version: 1.0 
Bnd-LastModified: 1486560203107 
Build-Jdk: 1.8.0_121 
Bundle-Description: Persistence 
Bundle-ManifestVersion: 2 
Bundle-Name: example.persistence.impl 
Bundle-SymbolicName: example.persistence.impl 
Bundle-Version: 1.0.0.SNAPSHOT 
Created-By: Apache Maven Bundle Plugin 
Export-Package: example.persistence.impl;version="1.0.0";uses:="javax.pe 
rsistence,javax.xml.bind.annotation" 
Import-Package: javax.persistence;version="[2.1,3)",javax.xml.bind.annot 
ation 
Meta-Persistence: META-INF/persistence.xml 
Originally-Created-By: Apache Maven Bundle Plugin 
Provide-Capability: osgi.service;effective:=active;objectClass="org.apac 
he.aries.jpa.supplier.EmSupplier";osgi.unit.name=officialUnit,osgi.serv 
ice;effective:=active;objectClass="javax.persistence.EntityManagerFacto 
ry";osgi.unit.name=officialUnit,osgi.service;effective:=active;objectCl 
ass="org.apache.aries.jpa.template.JpaTemplate";osgi.unit.name=official 
Unit,osgi.service;effective:=active;objectClass="javax.persistence.Enti 
tyManager";osgi.unit.name=officialUnit 
Require-Capability: osgi.service;effective:=active;objectClass="javax.sq 
l.DataSource";filter:="(osgi.jndi.service.name=demo-db)",osgi.service;e 
ffective:=active;objectClass="javax.persistence.spi.PersistenceProvider 
";javax.persistence.provider="org.eclipse.persistence.jpa.PersistencePr 
ovider",osgi.extender;osgi.extender="aries.jpa",osgi.service;effective: 
=active;objectClass="javax.transaction.TransactionManager",osgi.ee;filt 
er:="(&(osgi.ee=JavaSE)(version=1.8))" 
Tool: Bnd-3.2.0.201605172007 

持久單元已成功使用OSGi Framework啓動協議在Eclipse中啓動成形。

Answer 1

因爲有許多運動部件，Jpa並不是無關緊要的。第一步是檢查你的持久性包是否被aries jpa容器找到。

首先要檢查的是，如果Persitence單元包的Manifest具有Meta-Persistence頭並指向persistence.xml，如：META-INF/persistence.xml。

如果你有這個，那麼jpa容器應該拿起這個包並解析你的persistence.xml。

接下來要檢查的是PersistenceProvider服務是否存在以及DataSource是否存在（如果使用的是DataSource）。

如果您使用的配置，然後不要忘記安裝必要的PAX-JDBC功能配置您的數據源：

feature:repo-add pax-jdbc 1.0.0 
feature:install pax-jdbc-config pax-jdbc-sqlite