java - How to include external entities on persistence.xml file -

i need include external entity class files on persistence.xml file, how can it?

i have multiple eclipse projects system's modules , have test in need use persistence unit that's inside project, so, how can make code "aware" of other entities? how can list them on persistence.xml file.

also, 1 more detail:

java.lang.illegalargumentexception: exception occurred while creating query in entitymanager:  exception description: problem compiling [delete jpaprofile].  [12, 22] abstract schema type 'jpaprofile' unknown.     @ org.eclipse.persistence.internal.jpa.entitymanagerimpl.createquery(entitymanagerimpl.java:1605) 

this error shows on failure trace.

you can explicitly state classes use using <class> tag.

<class>com.test.jpa.entity.test</class> 

so long class on class path, should go.