code: public synchronized Database get_db_obj() throws DevFailed {
          if (ApiUtil.getOrb() == null) {
              create_orb();
          }
  
          // If first time, create vector
          // ---------------------------------------------------------------
          if (db_list == null) {
              db_list = new ArrayList<Database>();
          }
          // If first time, create Database object
          // -----------------------------------------------------------
          if (defaultDatabase == null) {
              defaultDatabase = new Database();
              db_list.add(defaultDatabase);
          }
          return db_list.get(0);
      }
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