question: public Collection < Extension > build ( Collection < String > urls ) { List < Extension > extensions = new LinkedList < Extension > ( ) ; for ( String urlAsString : urls ) { try { Extension e = build ( urlAsString ) ; if ( e != null ) { extensions . add ( e ) ; } } catch ( IOException e ) { LOG . error ( "Unable to access extension definition defined at " + urlAsString , e ) ; } catch ( SAXException e ) { LOG . error ( "Unable to parse extension definition defined at " + urlAsString , e ) ; } } return extensions ; }
target:  Builds extensions from the supplied Strings which should be URLs.