// Hand-coded base class
public abstract class AbstractNodeIdentifierMap<V> extends AbstractMap<NodeIdentifier, V> implements Immutable {
  @Override
  public final V get(Object obj) {
    return obj instanceof NodeIdentifier nid ? get(nid.getType()) : null;
  }

  protected abstract V get(QName qname);
}

// Generated
final class NodeIdenfierMapXXYYZZ<V> extends AbstractNodeIdentifierMap<V> {
  // ... for each child QNameModule
  private static final QNameModule MODULE0;
  // ... also we may need constants for QNames for things like entrySet(), keySet(), etc.
  
  // actually something reasonably-derived from QName?
  private final V v0_0;
  private final V v0_1;

  @Override
  protected V get(QName qnamej) {
    final var module = qname.getModule();
    if (MODULE0.equals(module)) {
        return get0(qname.getLocalName());
    }
    // else ... if we have more QNameModule

    return null;
  }

  // peeled for each QNameModule
  private V get0(String localName) {
    return switch (localName) {
      case "some-name" -> field0_0;
      case "other-name" -> field0_1;
      default -> null;
    }
  }
}