broker = pool.get(SecurityManager.SYSTEM_USER);
broker = pool.get(user);
    public void testStore() throws Exception {        BrokerPool pool = BrokerPool.getInstance();        DBBroker broker = null;        try {            broker = pool.get(SecurityManager.SYSTEM_USER);            Collection collection = broker.getOrCreateCollection("/db/test");            org.exist.dom.DocumentImpl doc =                 collection.addDocument(broker, "test.xml", XML, "text/xml");            broker.flush();            broker.saveCollection(collection);            System.out.println("testStore(): " + doc.printTreeLevelOrder());        } finally {            pool.release(broker);        }    }