Program: 65177
Project: 65177
Buggy source:
/** 
 * INTERNAL:
 */
private void openStartElement(XPathFragment xPathFragment,NamespaceResolver namespaceResolver,boolean addOpenBrace){
  try {
    Level newLevel=null;
    Level position=null;
    if (levels.isEmpty()) {
      newLevel=new Level(true,true);
      levels.push(newLevel);
    }
 else {
      position=levels.peek();
      newLevel=new Level(true,true);
      levels.push(newLevel);
      if (position.isFirst()) {
        position.setFirst(false);
      }
 else {
        writer.write(',');
      }
    }
    if (xPathFragment.nameIsText()) {
      if (position != null && position.isCollection() && position.isEmptyCollection()) {
        if (!charactersAllowed) {
          throw JAXBException.jsonValuePropertyRequired("String_Node_Str");
        }
        writer.write('[');
        position.setEmptyCollection(false);
        position.setNeedToOpenComplex(false);
        charactersAllowed=true;
        return;
      }
    }
    if (position == null || !position.isCollection() || position.isEmptyCollection()) {
      if (position != null && position.needToOpenComplex) {
        writer.write('{');
        position.needToOpenComplex=false;
        position.needToCloseComplex=true;
      }
      writeKey(xPathFragment);
      if (position != null && position.isEmptyCollection()) {
        XPathFragment nextFragment=xPathFragment.getNextFragment();
        if (nextFragment != null && !nextFragment.nameIsText() && !nextFragment.isAttribute()) {
          newLevel.setEmptyCollection(true);
          newLevel.setCollection(true);
          position.setEmptyCollection(false);
        }
 else {
          writer.write('[');
          position.setEmptyCollection(false);
        }
      }
    }
    charactersAllowed=true;
  }
 catch (  IOException e) {
    throw XMLMarshalException.marshalException(e);
  }
}

Fixed version (ground truth):
/** 
 * INTERNAL:
 */
public void openStartElement(XPathFragment xPathFragment,NamespaceResolver namespaceResolver){
  try {
    Level newLevel=null;
    Level position=null;
    if (levels.isEmpty()) {
      newLevel=new Level(true,true);
      levels.push(newLevel);
    }
 else {
      position=levels.peek();
      newLevel=new Level(true,true);
      levels.push(newLevel);
      if (position.isFirst()) {
        position.setFirst(false);
      }
 else {
        writer.write(',');
      }
    }
    if (xPathFragment.nameIsText()) {
      if (position != null && position.isCollection() && position.isEmptyCollection()) {
        if (!charactersAllowed) {
          throw JAXBException.jsonValuePropertyRequired("String_Node_Str");
        }
        writer.write('[');
        position.setEmptyCollection(false);
        position.setNeedToOpenComplex(false);
        charactersAllowed=true;
        return;
      }
    }
    if (position != null && position.needToOpenComplex) {
      writer.write('{');
      position.needToOpenComplex=false;
      position.needToCloseComplex=true;
    }
    if (!(position.isCollection() && !position.isEmptyCollection())) {
      writeKey(xPathFragment);
      if (position.isCollection() && position.isEmptyCollection()) {
        writer.write('[');
        position.setEmptyCollection(false);
      }
    }
    charactersAllowed=true;
  }
 catch (  IOException e) {
    throw XMLMarshalException.marshalException(e);
  }
}