apache/hadoop · error · IllegalArgumentException

Query param key should not be empty

Error message

Query param key should not be empty

What it means

Error "Query param key should not be empty" thrown in apache/hadoop.

Source

Thrown at hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azurebfs/utils/UriUtils.java:142

  /**
   * Generic function to mask a set of query parameters partially/fully and
   * return the resultant query string
   * @param keyValueList List of NameValuePair instances for query keys/values
   * @param queryParamsForFullMask values for these params will appear as "XXXX"
   * @param queryParamsForPartialMask values will be masked with 'X', except for
   *                                  the last PARTIAL_MASK_VISIBLE_LEN characters
   * @param queryLen to initialize StringBuilder for the masked query
   * @return the masked url query part
   */
  public static String maskUrlQueryParameters(List<NameValuePair> keyValueList,
      Set<String> queryParamsForFullMask,
      Set<String> queryParamsForPartialMask, int queryLen) {
    StringBuilder maskedUrl = new StringBuilder(queryLen);
    for (NameValuePair keyValuePair : keyValueList) {
      String key = keyValuePair.getName();
      if (key.isEmpty()) {
        throw new IllegalArgumentException("Query param key should not be empty");
      }
      String value = keyValuePair.getValue();
      maskedUrl.append(key);
      maskedUrl.append(EQUAL);
      if (value != null && !value.isEmpty()) { //no mask
        if (queryParamsForFullMask.contains(key)) {
          maskedUrl.append(FULL_MASK);
        } else if (queryParamsForPartialMask.contains(key)) {
          int valueLen = value.length();
          int maskedLen = valueLen > PARTIAL_MASK_VISIBLE_LEN
              ? PARTIAL_MASK_VISIBLE_LEN : valueLen / 2;
          maskedUrl.append(value, 0, valueLen - maskedLen);
          maskedUrl.append(StringUtils.repeat(CHAR_MASK, maskedLen));
        } else {
          maskedUrl.append(value);
        }
      }
      maskedUrl.append(AND_MARK);

View on GitHub (pinned to 2add963021)

Solutions

1. Pass a non-empty query parameter key when building the URI.
2. Fix caller logic that generates parameter names.

When it happens

Trigger: UriUtils is asked to add a query parameter with an empty key.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/3682029e3db5e4d7. Report an issue: GitHub.