code: private String computeUri(String target, String query, String anchor) {
  
          StringBuffer uri = new StringBuffer(64);
          uri.append(target);
          if (query != null) {
              uri.append('?');
              uri.append(query);
          }
          if (anchor != null) {
              uri.append('#');
              uri.append(anchor);
          }
          return uri.toString();
  
      }
docs: Helper method for creating a uri from its components.<p>
  
  @param target the uri target
  @param query the uri query component
  @param anchor the uri anchor component
  
  @return the uri