output: #fixed code
                                  @Override
      public User getWithNetworksById(long id) {
          User user = find(id);
  
          Set<Long> networkIds = userNetworkDao.findNetworksForUser(id);
          if (networkIds == null) {
              return user;
          }
          Set<Network> networks = new HashSet<>();
          for (Long networkId : networkIds) {
              Network network = networkDao.find(networkId);
              networks.add(network);
          }
          user.setNetworks(networks);
          return user;
      }
input: #vulnerable code 
                                  @Override
      public User getWithNetworksById(long id) {
          User user = find(id);
  
          Set<Long> networkIds = userNetworkDao.findNetworksForUser(id);
          Set<Network> networks = new HashSet<>();
          for (Long networkId : networkIds) {
              Network network = networkDao.find(networkId);
              networks.add(network);
          }
          user.setNetworks(networks);
          return user;
      } 
                              #location 7 
                              #vulnerability type NULL_DEREFERENCE