code: public void setPermittedAddresses(List<DomainMatcher> addrs) {
          if (addrs == null || addrs.isEmpty()) {
              ((HierarchicalConfiguration) getConfig()).clearTree(ADDRESS_KEY);
  
              this.permittedAddresses = Collections.emptyList();
              this.permittedAddressesEnabled = Collections.emptyList();
              return;
          }
  
          this.permittedAddresses = new ArrayList<>(addrs);
  
          ((HierarchicalConfiguration) getConfig()).clearTree(ADDRESS_KEY);
  
          int size = addrs.size();
          ArrayList<DomainMatcher> enabledAddrs = new ArrayList<>(size);
          for (int i = 0; i < size; ++i) {
              String elementBaseKey = ADDRESS_KEY + "(" + i + ").";
              DomainMatcher addr = addrs.get(i);
  
              getConfig().setProperty(elementBaseKey + ADDRESS_VALUE_KEY, addr.getValue());
              getConfig().setProperty(elementBaseKey + ADDRESS_REGEX_KEY, addr.isRegex());
              getConfig().setProperty(elementBaseKey + ADDRESS_ENABLED_KEY, addr.isEnabled());
  
              if (addr.isEnabled()) {
                  enabledAddrs.add(addr);
              }
          }
  
          enabledAddrs.trimToSize();
          this.permittedAddressesEnabled = enabledAddrs;
      }
docs: Sets the client addresses that will be allowed to access the API.
  
  @param addrs the client addresses that will be allowed to access the API.
  @since 2.6.0