stanfordnlp/CoreNLP · error · RuntimeIOException

Failed to find node " + ie.target + "-" + ie.targetCopy

Error message

Failed to find node " + ie.target + "-" + ie.targetCopy

What it means

RuntimeIOException from AnnotationSerializer's graph reconstruction when an edge references a node (source or target index-copy) that was not found in the deserialized node map — the serialized dependency graph is inconsistent or was produced by an incompatible version.

Solutions

1. Regenerate the annotation file with a matching CoreNLP version
2. Audit any custom serializer/filter code for node removal without edge cleanup
3. Validate the file against the schema; look for the specific missing target id in the message
4. Test with a fresh document serialized end-to-end to isolate writer vs. file corruption

Example fix

// before
// filter drops punctuation nodes but leaves edges referencing them
// after
// drop edges alongside removed nodes:
// edges.removeIf(e -> removed.contains(e.target));

// pre-validate a deserialized graph
for (SemanticGraphEdge e : graph.edgeIterable()) {
  if (e.getSource() == null || e.getTarget() == null)
    throw new IllegalStateException("Dangling edge in graph");
}

try {
  graph = convertIntermediateGraph(nodes, edges);
} catch (RuntimeIOException e) {
  if (e.getMessage().startsWith("Failed to find node")) {
    log.error("Edge references missing node: " + e.getMessage());
  } else throw e;
}

When it happens

Trigger: Deserializing a SemanticGraph whose IntermediateEdge target (nodeId, copy) has no matching node entry — corrupted file, writer/reader version mismatch, or custom code pruning nodes while keeping edges.

Common situations: Merging or truncating serialized annotation files, custom serialization pipelines that filter enhanced/ccprocessed dependencies, upgrading CoreNLP between serialization format changes.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• Failed to find node " + ie.source + "-" + ie.sourceCopy
• ERROR: Invalid dependency node line
• ERROR: Invalid format for dependency graph
• ERROR: Serialized data does not contain an Annotation!
• Unknown general relation

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/2dae3595cde9e908. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/pipeline/AnnotationSerializer.java:169

          word.setIndex(in.index);
        }

        nodeMap.put(word.index(), word.copyCount(), word);
        graph.addVertex(word);
        if (in.isRoot) {
          graph.addRoot(word);
        }
      }

      // add all edges to the actual graph
      for (IntermediateEdge ie: edges) {
        IndexedWord source = nodeMap.get(ie.source, ie.sourceCopy);
        if (source == null) {
          throw new RuntimeIOException("Failed to find node " + ie.source + "-" + ie.sourceCopy);
        }
        IndexedWord target = nodeMap.get(ie.target, ie.targetCopy);
        if (target == null) {
          throw new RuntimeIOException("Failed to find node " + ie.target + "-" + ie.targetCopy);
        }
        // assert(target != null);
        synchronized (LOCK) {
          // this is not thread-safe: there are static fields in GrammaticalRelation
          GrammaticalRelation rel = GrammaticalRelation.valueOf(ie.dep);
          graph.addEdge(source, target, rel, 1.0, ie.isExtra);
        }
      }

      // compute root nodes if they weren't stored in the graph
      if ( ! graph.isEmpty() && graph.getRoots().isEmpty()) {
        graph.resetRoots();
      }

      return graph;
    }
  }

View on GitHub (pinned to 1b7edd19c4)