apache/hadoop · error · NoSuchElementException

No attribute for {}

Error message

No attribute for {}

What it means

FileAttribute.getAttribute(char) in CommandWithDestination maps each character of the -p value of 'hdfs dfs -cp' to a preserve-attribute enum. Valid characters are the (case-insensitive) first letters of the enum: t=TIMESTAMPS, o=OWNERSHIP, p=PERMISSION, a=ACL, x=XATTR. Any other character throws NoSuchElementException('No attribute for c') from CopyCommands.Cp.popPreserveOption (CopyCommands.java:204), which crashes option processing with a raw runtime exception.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/CommandWithDestination.java:144

    if (preserve) {
      preserve(FileAttribute.TIMESTAMPS);
      preserve(FileAttribute.OWNERSHIP);
      preserve(FileAttribute.PERMISSION);
    } else {
      preserveStatus.clear();
    }
  }
  
  protected enum FileAttribute {
    TIMESTAMPS, OWNERSHIP, PERMISSION, ACL, XATTR;

    public static FileAttribute getAttribute(char symbol) {
      for (FileAttribute attribute : values()) {
        if (attribute.name().charAt(0) == Character.toUpperCase(symbol)) {
          return attribute;
        }
      }
      throw new NoSuchElementException("No attribute for " + symbol);
    }
  }
  
  private EnumSet<FileAttribute> preserveStatus = 
      EnumSet.noneOf(FileAttribute.class);
  
  /**
   * Checks if the input attribute should be preserved or not
   *
   * @param attribute - Attribute to check
   * @return boolean true if attribute should be preserved, false otherwise
   */
  private boolean shouldPreserve(FileAttribute attribute) {
    return preserveStatus.contains(attribute);
  }
  
  /**
   * Add file attributes that need to be preserved. This method may be

View on GitHub (pinned to 2add963021)

Solutions

1. Use only the letters t, o, p, a, x after -p (e.g. 'hdfs dfs -cp -ptop /src /dst')
2. Use plain '-p' with no suffix, which preserves all supported attributes
3. Remove any '=', commas, or words from the preserve specification - only a bare letter run is accepted

Example fix

# before
hdfs dfs -cp -pz /src /dst
# after
hdfs dfs -cp -p /src /dst
# or preserve only timestamps+permissions:
hdfs dfs -cp -ptp /src /dst

// validate a -p[attrs] suffix for hdfs dfs -cp before invoking
static boolean isValidPreserveSpec(String s) {
  for (char c : s.substring(2).toCharArray()) {
    if ("ptopaxPTOPAX".indexOf(c) < 0) return false; // p=permission t=timestamps o=ownership a=ACL x=xattr
  }
  return true;
}
if (arg.startsWith("-p") && arg.length() > 2 && !isValidPreserveSpec(arg)) {
  throw new IllegalArgumentException("-p accepts only t,o,p,a,x: " + arg);
}

// narrows a char to a valid FileAttribute symbol
static Optional<CommandWithDestination.FileAttribute> asAttribute(char c) {
  return switch (Character.toUpperCase(c)) {
    case 'T' -> Optional.of(FileAttribute.TIMESTAMPS);
    case 'O' -> Optional.of(FileAttribute.OWNERSHIP);
    case 'P' -> Optional.of(FileAttribute.PERMISSION);
    case 'A' -> Optional.of(FileAttribute.ACL);
    case 'X' -> Optional.of(FileAttribute.XATTR);
    default -> Optional.empty();
  };
}

When it happens

Trigger: 'hdfs dfs -cp -pz /src /dst' (no 'z' attribute), '-pm' or '--preserve=mode'-style GNU vocabulary pasted after -p, or a typo like '-pacl' where only single attribute letters are accepted.

Common situations: Users familiar with GNU cp's '--preserve=mode,links' syntax assuming the same words work after -p; uppercase/lowercase confusion is NOT a problem (matching is case-insensitive) but extra letters are; scripting after reading docs for a different Hadoop version.

Related errors

• Illegal option {}
• Not enough arguments: expected {} but got {}
• Too many arguments: expected {} but got {}
• unexpected URISyntaxException
• No such file or directory

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/ef87974e0adda0b6. Report an issue: GitHub.