is it possible to use Java API to get document details and formatting in 4.0 and 4.1 api

Hi all,

     I am  trying to open document from report engine in BI 4.0 and BI 4.1 using Java API. its throwing communication exception as shown below

     com.businessobjects.rebean.wi.CommunicationException: Cannot initialize Report Engine server. (Error: RWI 00226)

Question :

    1.) We can use Java api for BI 4.0 and BI 4.1  or we must use Restful web service only??

     while using  Restful web services. i am able to login and get document details and properties but i am unable to use specification url ( {url}/raylight/v1/documents/" {document_id} "/reports/{report_id}/specification ). i am getting following error code while using this url

<error_code>RWS 00058</error_code>