apache/hadoop · error · IOException

Expecting a line not the end of stream

Error message

Expecting a line not the end of stream

What it means

Error "Expecting a line not the end of stream" thrown in apache/hadoop.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java:79

    void startRefresh() throws IOException {
      run();
    }
    @Override
    public String toString() {
      return
          "du -sk " + getDirPath() + "\n" + used.get() + "\t" + getDirPath();
    }

    @Override
    protected String[] getExecString() {
      return new String[]{"du", "-sk", getDirPath()};
    }

    @Override
    protected void parseExecResult(BufferedReader lines) throws IOException {
      String line = lines.readLine();
      if (line == null) {
        throw new IOException("Expecting a line not the end of stream");
      }
      String[] tokens = line.split("\t");
      if (tokens.length == 0) {
        throw new IOException("Illegal du output");
      }
      setUsed(Long.parseLong(tokens[0]) * 1024);
    }

  }


  public static void main(String[] args) throws Exception {
    String path = ".";
    if (args.length > 0) {
      path = args[0];
    }

    GetSpaceUsed du = new GetSpaceUsed.Builder().setPath(new File(path))

View on GitHub (pinned to 2add963021)

Solutions

1. Verify the du command produced output; an empty stream means du failed or the path is invalid.
2. Check stderr of the du process for the real error.
3. Ensure the path being measured exists and is readable.

When it happens

Trigger: Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java:79 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/549f490014c7aec5. Report an issue: GitHub.