覆盖Maven-Bundle-Plugin中的要求-功能

Question

我的问题类似于this one，但我正在使用Maven包插件来实现相同的最终结果。

我正在构建一个包含persistence.xml文件的包，并且我发现maven-bundle-plugin会在清单中自动生成以下标题：

Require-Capability:osgi.service;effective:=active;objectClass=javax.persistence.spi.PersistenceProvider;javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl,
Require-Capability: osgi.extender;osgi.extender=aries.jpa, 
Require-Capability: osgi.service;effective:=active;objectClass=javax.sql.DataSource;filter:="(osgi.jndi.service.name=jdbc/test)"

这本身并不是一个问题，但是我使用的是Karaf，我想在我自己的一个特性中部署这个包和其他包和Karaf特性。当我这样做时，它会失败，因为OSGi无法实现osgi.service;effective:=active;objectClass=javax.persistence.spi.PersistenceProvider;javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl的功能，即使我指定了要同时安装的openjpa特性。我发现我可以通过将effective:=active改为resolution:=optional来解决这个问题。

为了构建我的包，我尝试了以下Maven插件配置：

<plugin>
    <groupId>org.apache.felix</groupId>
    <artifactId>maven-bundle-plugin</artifactId>
    <version>3.3.0</version>
    <extensions>true</extensions>
    <configuration>
        <instructions>
            <Export-Package>com.example
            </Export-Package>
            <Include-Resource>
                        META-INF/persistence.xml=${project.build.directory}/classes/META-INF/persistence.xml,
                        {maven-resources}
            </Include-Resource>
            <Meta-Persistence>META-INF/persistence.xml</Meta-Persistence>
            <Require-Capability>
                        osgi.service;resolution:=optional;objectClass=javax.persistence.spi.PersistenceProvider;javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl,
                        osgi.extender;resolution:=optional;osgi.extender=aries.jpa,
                        osgi.service;resolution:=optional;objectClass=javax.sql.DataSource;filter:="(osgi.jndi.service.name=jdbc/test)"
            </Require-Capability>
        </instructions>
    </configuration>
</plugin>

然而，我得到的问题与上面的链接问题相同，即清单中重复的要求。

我还从上述问题的链接中看到，对bnd (bnd问题#1364)进行了更改，但这似乎只适用于注释吗？是否有方法配置Maven插件以防止重复的需求？

更新#1

我的示例代码可在GitHub (karaf_features分支)获得：features

它由3个模块组成，但只有2个模块对此问题感兴趣，即simple和simple-datasource。

simple是“持久性单元”，包含persistence.xml。它也是生成“尴尬”(但实际的需求) <Require-Capability>头的包。

simple-datasource向持久化单元提供数据源，并包含用于安装simple、simple-datasource包和所有所需的第三方捆绑包(通过Karaf特性)的Karaf特性。特性XML包含：

<feature name="simple-datasource" description="simple-datasource" version="1.0.0.SNAPSHOT">
    <feature version="4.1.1">jdbc</feature>
    <feature version="2.6.0">jpa</feature>
    <feature version="2.4.1">openjpa</feature>
    <feature version="1.0.1">pax-jdbc-mariadb</feature>
    <bundle>mvn:com.javatechnics.jpa/simple-datasource/1.0.0-SNAPSHOT</bundle>
    <bundle>mvn:com.javatechnics.jpa/simple/1.0.0-SNAPSHOT</bundle>
</feature>

因此，在Karaf中安装我的特性，我得到了以下错误：

执行命令错误:无法解决根:缺少需求根osgi.identity；osgi.Identity=simple-数据源；type=karaf.feature；version=“1.0.SNAPSHOT，1.0.SNAPSHOT”；version= [原因:无法解决简单-数据源/1.0.0.SNAPSHOT:缺少需求简单-数据源/1.0.SNAPSHOT osgi.identity；osgi.identity=com.javatechnics.jpa.simple；type=osgi.bundle；version=“1.0.SNAPSHOT，1.0.0.SNAPSHOT”；resolution:=mandatory [原因:无法解析com.javatechnics.jpa.simple/1.0.0.SNAPSHOT:缺少需求com.javatechnics.jpa.Simple/1.0.SNAPSHOT osgi.service；objectClass=javax.persistence.spi.PersistenceProvider；javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl；effective：=active]

对我来说，这个错误几乎像一个循环引用问题，但我不知道怎么回事。

检查simple包的头：

simple (59)
-----------
Bnd-LastModified = 1513115007378
Build-Jdk = 1.8.0_144
Built-By = kerry
Created-By = Apache Maven Bundle Plugin
Manifest-Version = 1.0
Meta-Persistence = META-INF/persistence.xml
Tool = Bnd-3.2.0.201605172007

Bundle-Blueprint = OSGI-INF/blueprint/blueprint.xml
Bundle-ManifestVersion = 2
Bundle-Name = simple
Bundle-SymbolicName = com.javatechnics.jpa.simple
Bundle-Version = 1.0.0.SNAPSHOT

Export-Service = 
com.javatechnics.jpa.dao.BookServiceDao;ServiceManager=Blueprint;name=
BookServiceDao
Provide-Capability = 
osgi.service;effective:=active;objectClass=javax.persistence.EntityManagerFactory;osgi.unit.name=test,
osgi.service;effective:=active;objectClass=org.apache.aries.jpa.template.JpaTemplate;osgi.unit.name=test,
osgi.service;effective:=active;objectClass=javax.persistence.EntityManager;osgi.unit.name=test,
osgi.service;effective:=active;objectClass=org.apache.aries.jpa.supplier.EmSupplier;osgi.unit.name=test
Require-Capability = 
osgi.service;effective:=active;javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl;objectClass=javax.persistence.spi.PersistenceProvider,
osgi.extender;osgi.extender=aries.jpa,
 osgi.service;effective:=active;filter:=(osgi.jndi.service.name=jdbc/test);objectClass=javax.sql.DataSource,
osgi.ee;filter:=(&(osgi.ee=JavaSE)(version=1.5))

Export-Package = 
com.javatechnics.jpa;uses:="com.javatechnics.jpa.dao,javax.persistence";version=1.0.0,
com.javatechnics.jpa.dao;uses:=com.javatechnics.jpa;version=1.0.0
Import-Package = 
com.javatechnics.jpa,
com.javatechnics.jpa.dao,
javax.persistence;version="[1.1,2)",
org.osgi.service.blueprint;version="[1.0.0,2.0.0)"

Answer 1

如果您知道一个包(我们称之为xyz )提供了PersistenceProvider服务，那么您可以编写一个附加的包，只需这样做：

Require-Bundle: xyz; bundle-version="[...)"
Provide-Capability: osgi.service;
    objectClass=javax.persistence.spi.PersistenceProvider;
    javax.persistence.provider=org.apache.openjpa.persistence.PersistenceProviderImpl;
    effective:=active

这在本质上增强了包xyz的功能，它将解决包中的需求，而代价是添加一个其他无用的包。

这仍然是一种解决办法，但比从包中移除真正的需求要好。