apache/hadoop · error · IOException

Expected nodetype

Error message

Expected nodetype

What it means

Error "Expected nodetype" thrown in apache/hadoop.

Source

Thrown at hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/join/Parser.java:97

  /**
   * Tagged-union type for tokens from the join expression.
   * @see Parser.TType
   */
  @InterfaceAudience.Public
  @InterfaceStability.Evolving
  public static class Token {

    private TType type;

    Token(TType type) {
      this.type = type;
    }

    public TType getType() { return type; }
    
    public Node getNode() throws IOException {
      throw new IOException("Expected nodetype");
    }
    
    public double getNum() throws IOException {
      throw new IOException("Expected numtype");
    }
    
    public String getStr() throws IOException {
      throw new IOException("Expected strtype");
    }
  }

  @InterfaceAudience.Public
  @InterfaceStability.Evolving
  public static class NumToken extends Token {
    private double num;
    public NumToken(double num) {
      super(TType.NUM);
      this.num = num;

View on GitHub (pinned to 2add963021)

Solutions

1. Fix the join expression syntax: an identifier naming a node/stream type is required at this position.
2. Check the expression against the grammar: <expr> ::= <op>(<input>[,<input>]*) with valid InputFormat class names.

When it happens

Trigger: Thrown by Parser.Ttype/Node parsing when a join expression token is expected to be a node (stream) type but a different token type was found. Check the join expression syntax: identifiers for input streams must be declared correctly.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/10e43e0b76be306e. Report an issue: GitHub.