apache/hadoop · error · IllegalArgumentException

invalid codePath: className={} codePath={}

Error message

invalid codePath: className={} codePath={}

What it means

Error "invalid codePath: className={} codePath={}" thrown in apache/hadoop.

Source

Thrown at hadoop-tools/hadoop-streaming/src/main/java/org/apache/hadoop/streaming/StreamUtil.java:98

    String codePath;
    if (classUrl != null) {
      boolean inJar = classUrl.getProtocol().equals("jar");
      codePath = classUrl.toString();
      if (codePath.startsWith("jar:")) {
        codePath = codePath.substring("jar:".length());
      }
      if (codePath.startsWith("file:")) { // can have both
        codePath = codePath.substring("file:".length());
      }
      if (inJar) {
        // A jar spec: remove class suffix in /path/my.jar!/package/Class
        int bang = codePath.lastIndexOf('!');
        codePath = codePath.substring(0, bang);
      } else {
        // A class spec: remove the /my/package/Class.class portion
        int pos = codePath.lastIndexOf(relPath);
        if (pos == -1) {
          throw new IllegalArgumentException("invalid codePath: className=" + className
                                             + " codePath=" + codePath);
        }
        codePath = codePath.substring(0, pos);
      }
    } else {
      codePath = null;
    }
    return codePath;
  }

  static String qualifyHost(String url) {
    try {
      return qualifyHost(new URL(url)).toString();
    } catch (IOException io) {
      return url;
    }
  }

View on GitHub (pinned to 2add963021)

Solutions

1. Ensure the class is packaged in the job jar and the code path (jar/classpath entry) is valid and readable.

When it happens

Trigger: StreamUtil resolves a class's code source path that is null or otherwise invalid, e.g. the class was loaded by the bootstrap classloader.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/e9974d2ac147d3a7. Report an issue: GitHub.