As Ivan explains, there are no official Sunacle jars in Maven. However, it is quite often the case that an implementer of a given API will publish an artifact for that API (the API itself, rather than their implementation of it.
In the case of JPA 2.0, Hibernate publish org.hibernate.javax.persistence:hibernate-jpa-2.0-api, which contains just the javax.persistence
classes, and no Hibernate-specific stuff.
My build.gradle therefore says:
dependencies {
compile group: 'org.hibernate.javax.persistence', name: 'hibernate-jpa-2.0-api', version: '1.0.1.Final'
runtime group: 'org.hibernate', name: 'hibernate-entitymanager', version: '4.1.4.Final'
}
Which puts Hibernate's release of the API on the compile classpath, and their implementation on the runtime classpath.