Program: 64801
Project: 64801
Buggy source:
public void startUnmappedElement(String namespaceURI,String localName,String qName,Attributes atts) throws SAXException {
  if (this.unmarshaller.getMediaType() == MediaType.APPLICATION_XML && null == selfRecords) {
    ErrorHandler errorHandler=xmlReader.getErrorHandler();
    if (null != errorHandler) {
      StringBuilder messageBuilder=new StringBuilder("String_Node_Str");
      if (null != namespaceURI) {
        messageBuilder.append(namespaceURI);
      }
      messageBuilder.append("String_Node_Str");
      messageBuilder.append(localName);
      messageBuilder.append("String_Node_Str");
      List<XPathNode> nonAttributeChildren=xPathNode.getNonAttributeChildren();
      if (nonAttributeChildren == null || nonAttributeChildren.size() == 0) {
        messageBuilder.append("String_Node_Str");
      }
 else {
        for (int x=0, size=nonAttributeChildren.size(); x < size; x++) {
          XPathFragment nonAttributeChildXPathFragment=nonAttributeChildren.get(x).getXPathFragment();
          messageBuilder.append("String_Node_Str");
          String nonAttributeChildXPathFragmentNamespaceURI=nonAttributeChildXPathFragment.getNamespaceURI();
          if (null != nonAttributeChildXPathFragmentNamespaceURI) {
            messageBuilder.append(nonAttributeChildXPathFragmentNamespaceURI);
          }
          messageBuilder.append('}');
          messageBuilder.append(nonAttributeChildXPathFragment.getLocalName());
          messageBuilder.append('>');
          if (x < size - 1) {
            messageBuilder.append(',');
          }
        }
      }
      errorHandler.warning(new SAXParseException(messageBuilder.toString(),documentLocator));
    }
  }
  if ((null != selfRecords) || (null == xmlReader) || isSelfRecord()) {
    if (-1 == unmappedLevel) {
      this.unmappedLevel=this.levelIndex;
    }
    return;
  }
  Class unmappedContentHandlerClass=unmarshaller.getUnmappedContentHandlerClass();
  UnmappedContentHandler unmappedContentHandler;
  if (null == unmappedContentHandlerClass) {
    unmappedContentHandler=DEFAULT_UNMAPPED_CONTENT_HANDLER;
  }
 else {
    try {
      PrivilegedNewInstanceFromClass privilegedNewInstanceFromClass=new PrivilegedNewInstanceFromClass(unmappedContentHandlerClass);
      unmappedContentHandler=(UnmappedContentHandler)privilegedNewInstanceFromClass.run();
    }
 catch (    ClassCastException e) {
      throw XMLMarshalException.unmappedContentHandlerDoesntImplement(e,unmappedContentHandlerClass.getName());
    }
catch (    IllegalAccessException e) {
      throw XMLMarshalException.errorInstantiatingUnmappedContentHandler(e,unmappedContentHandlerClass.getName());
    }
catch (    InstantiationException e) {
      throw XMLMarshalException.errorInstantiatingUnmappedContentHandler(e,unmappedContentHandlerClass.getName());
    }
  }
  UnmappedContentHandlerWrapper unmappedContentHandlerWrapper=new UnmappedContentHandlerWrapper(this,unmappedContentHandler);
  unmappedContentHandlerWrapper.startElement(namespaceURI,localName,qName,atts);
  xmlReader.setContentHandler(unmappedContentHandlerWrapper);
  xmlReader.setLexicalHandler(unmappedContentHandlerWrapper);
}

Fixed version (ground truth):
public void startUnmappedElement(String namespaceURI,String localName,String qName,Attributes atts) throws SAXException {
  if (this.unmarshaller.getMediaType() == MediaType.APPLICATION_XML && null == selfRecords) {
    ErrorHandler errorHandler=xmlReader.getErrorHandler();
    if (null != errorHandler) {
      StringBuilder messageBuilder=new StringBuilder("String_Node_Str");
      if (null != namespaceURI) {
        messageBuilder.append(namespaceURI);
      }
      messageBuilder.append("String_Node_Str");
      messageBuilder.append(localName);
      messageBuilder.append("String_Node_Str");
      List<XPathNode> nonAttributeChildren=xPathNode.getNonAttributeChildren();
      if (nonAttributeChildren == null || nonAttributeChildren.size() == 0) {
        messageBuilder.append("String_Node_Str");
      }
 else {
        for (int x=0, size=nonAttributeChildren.size(); x < size; x++) {
          XPathFragment nonAttributeChildXPathFragment=nonAttributeChildren.get(x).getXPathFragment();
          messageBuilder.append("String_Node_Str");
          String nonAttributeChildXPathFragmentNamespaceURI=nonAttributeChildXPathFragment.getNamespaceURI();
          if (null != nonAttributeChildXPathFragmentNamespaceURI) {
            messageBuilder.append(nonAttributeChildXPathFragmentNamespaceURI);
          }
          messageBuilder.append('}');
          messageBuilder.append(nonAttributeChildXPathFragment.getLocalName());
          messageBuilder.append('>');
          if (x < size - 1) {
            messageBuilder.append(',');
          }
        }
      }
      errorHandler.warning(new SAXParseException(messageBuilder.toString(),getDocumentLocator()));
    }
  }
  if ((null != selfRecords) || (null == xmlReader) || isSelfRecord()) {
    if (-1 == unmappedLevel) {
      this.unmappedLevel=this.levelIndex;
    }
    return;
  }
  Class unmappedContentHandlerClass=unmarshaller.getUnmappedContentHandlerClass();
  UnmappedContentHandler unmappedContentHandler;
  if (null == unmappedContentHandlerClass) {
    unmappedContentHandler=DEFAULT_UNMAPPED_CONTENT_HANDLER;
  }
 else {
    try {
      PrivilegedNewInstanceFromClass privilegedNewInstanceFromClass=new PrivilegedNewInstanceFromClass(unmappedContentHandlerClass);
      unmappedContentHandler=(UnmappedContentHandler)privilegedNewInstanceFromClass.run();
    }
 catch (    ClassCastException e) {
      throw XMLMarshalException.unmappedContentHandlerDoesntImplement(e,unmappedContentHandlerClass.getName());
    }
catch (    IllegalAccessException e) {
      throw XMLMarshalException.errorInstantiatingUnmappedContentHandler(e,unmappedContentHandlerClass.getName());
    }
catch (    InstantiationException e) {
      throw XMLMarshalException.errorInstantiatingUnmappedContentHandler(e,unmappedContentHandlerClass.getName());
    }
  }
  UnmappedContentHandlerWrapper unmappedContentHandlerWrapper=new UnmappedContentHandlerWrapper(this,unmappedContentHandler);
  unmappedContentHandlerWrapper.startElement(namespaceURI,localName,qName,atts);
  xmlReader.setContentHandler(unmappedContentHandlerWrapper);
  xmlReader.setLexicalHandler(unmappedContentHandlerWrapper);
}