apache/hadoop · error · IOException

{className} instantiation exception.

Error message

{className} instantiation exception.

What it means

Error "{className} instantiation exception." thrown in apache/hadoop.

Source

Thrown at hadoop-tools/hadoop-aliyun/src/main/java/org/apache/hadoop/fs/aliyun/oss/AliyunOSSUtils.java:138

        try {
          credentials =
              (CredentialsProvider)credClass.getDeclaredConstructor(
                  URI.class, Configuration.class).newInstance(uri, conf);
        } catch (NoSuchMethodException | SecurityException e) {
          credentials =
              (CredentialsProvider)credClass.getDeclaredConstructor()
              .newInstance();
        }
      } catch (ClassNotFoundException e) {
        throw new IOException(className + " not found.", e);
      } catch (NoSuchMethodException | SecurityException e) {
        throw new IOException(String.format("%s constructor exception.  A " +
            "class specified in %s must provide an accessible constructor " +
            "accepting URI and Configuration, or an accessible default " +
            "constructor.", className, CREDENTIALS_PROVIDER_KEY),
            e);
      } catch (ReflectiveOperationException | IllegalArgumentException e) {
        throw new IOException(className + " instantiation exception.", e);
      }
    }

    return credentials;
  }

  /**
   * Turns a path (relative or otherwise) into an OSS key, adding a trailing
   * "/" if the path is not the root <i>and</i> does not already have a "/"
   * at the end.
   *
   * @param key OSS key or ""
   * @return the with a trailing "/", or, if it is the root key, "".
   */
  public static String maybeAddTrailingSlash(String key) {
    if (StringUtils.isNotEmpty(key) && !key.endsWith("/")) {
      return key + '/';
    } else {

View on GitHub (pinned to 2add963021)

Solutions

1. Check the class named in the configuration can be instantiated (not abstract, accessible constructor); inspect the logged cause.

When it happens

Trigger: Thrown at hadoop-tools/hadoop-aliyun/src/main/java/org/apache/hadoop/fs/aliyun/oss/AliyunOSSUtils.java:138 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/4bb45a655cc06cfc. Report an issue: GitHub.