Program: 44122
Project: 44122
Buggy source:
/** 
 * Web service operation
 */
@WebMethod(operationName="String_Node_Str") public boolean processPurchaseOrder(@WebParam(name="String_Node_Str") PurchaseOrder aPO){
  MessageContext ctxt=wsc.getMessageContext();
  ServletContext req=(ServletContext)ctxt.get(ctxt.SERVLET_CONTEXT);
  String path=req.getRealPath("String_Node_Str");
  ORDERS_XML=path + "String_Node_Str" + ORDERS_XML;
  if (aPO.getUnitPrice() >= aPO.getProduct().getUnitPrice()) {
    if (produce(aPO.getProduct().getProductName(),aPO.getQuantity())) {
      System.out.println("String_Node_Str");
      File file=new File(ORDERS_XML);
      try {
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        DocumentBuilder db=dbf.newDocumentBuilder();
        InputSource is=new InputSource();
        is.setCharacterStream(new FileReader(file));
        Document doc=db.parse(is);
        Element root=doc.getDocumentElement();
        Element e=doc.createElement("String_Node_Str");
        String keys[]={"String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str"};
        String values[]={aPO.getOrderNum(),aPO.getCustomerRef(),aPO.getProduct().getProductName(),Integer.toString(aPO.getQuantity()),Float.toString(aPO.getUnitPrice())};
        for (int i=0; i < keys.length; i++) {
          Element tmp=doc.createElement(keys[i]);
          tmp.setTextContent(values[i]);
          e.appendChild(tmp);
        }
        Element status=doc.createElement("String_Node_Str");
        status.setTextContent("String_Node_Str");
        e.appendChild(status);
        Element total=doc.createElement("String_Node_Str");
        float orderTotal=aPO.getQuantity() * aPO.getUnitPrice();
        total.setTextContent(Float.toString(orderTotal));
        e.appendChild(total);
        root.appendChild(e);
        TransformerFactory tf=TransformerFactory.newInstance();
        Transformer m=tf.newTransformer();
        DOMSource source=new DOMSource(root);
        StreamResult result=new StreamResult(file);
        m.transform(source,result);
      }
 catch (      Exception e) {
        System.out.println("String_Node_Str" + e.getMessage());
      }
      return true;
    }
  }
  System.out.println("String_Node_Str");
  return false;
}

Fixed version (ground truth):
/** 
 * Web service operation
 */
@WebMethod(operationName="String_Node_Str") public boolean processPurchaseOrder(@WebParam(name="String_Node_Str") PurchaseOrder aPO){
  MessageContext ctxt=wsc.getMessageContext();
  ServletContext req=(ServletContext)ctxt.get(ctxt.SERVLET_CONTEXT);
  String path=req.getRealPath("String_Node_Str");
  if (!ORDERS_XML.startsWith(path))   ORDERS_XML=path + "String_Node_Str" + ORDERS_XML;
  if (aPO.getUnitPrice() >= aPO.getProduct().getUnitPrice()) {
    if (produce(aPO.getProduct().getProductName(),aPO.getQuantity())) {
      System.out.println("String_Node_Str");
      File file=new File(ORDERS_XML);
      try {
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        DocumentBuilder db=dbf.newDocumentBuilder();
        InputSource is=new InputSource();
        is.setCharacterStream(new FileReader(file));
        Document doc=db.parse(is);
        Element root=doc.getDocumentElement();
        Element e=doc.createElement("String_Node_Str");
        String keys[]={"String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str","String_Node_Str"};
        String values[]={aPO.getOrderNum(),aPO.getCustomerRef(),aPO.getProduct().getProductName(),Integer.toString(aPO.getQuantity()),Float.toString(aPO.getUnitPrice())};
        for (int i=0; i < keys.length; i++) {
          Element tmp=doc.createElement(keys[i]);
          tmp.setTextContent(values[i]);
          e.appendChild(tmp);
        }
        Element status=doc.createElement("String_Node_Str");
        status.setTextContent("String_Node_Str");
        e.appendChild(status);
        Element total=doc.createElement("String_Node_Str");
        float orderTotal=aPO.getQuantity() * aPO.getUnitPrice();
        total.setTextContent(Float.toString(orderTotal));
        e.appendChild(total);
        root.appendChild(e);
        TransformerFactory tf=TransformerFactory.newInstance();
        Transformer m=tf.newTransformer();
        DOMSource source=new DOMSource(root);
        StreamResult result=new StreamResult(file);
        m.transform(source,result);
      }
 catch (      Exception e) {
        System.out.println("String_Node_Str" + e.getMessage());
      }
      return true;
    }
  }
  System.out.println("String_Node_Str");
  return false;
}