Program: 146759
Project: 146759
Buggy source:
public Stock[] parse() throws InvalidStructureException, IOException, XmlPullParserException {
  this.checkNode(new String[]{"String_Node_Str","String_Node_Str"});
  String name=parser.getName().toLowerCase();
  Vector<Stock> toWrite=new Vector<Stock>();
  String dateModified=parser.getAttributeValue(null,"String_Node_Str");
  if (dateModified == null) {
    throw new InvalidStructureException("String_Node_Str" + name + "String_Node_Str",this.parser);
  }
  Date modified=DateUtils.parseDateTime(dateModified);
  if (name.equals("String_Node_Str")) {
    String entityId=parser.getAttributeValue(null,"String_Node_Str");
    if (entityId == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    Stock s=retrieve(entityId);
    if (s == null) {
      s=new Stock(entityId,new Hashtable<String,Integer>());
    }
    while (this.nextTagInBlock("String_Node_Str")) {
      this.checkNode("String_Node_Str");
      String id=parser.getAttributeValue(null,"String_Node_Str");
      String quantityString=parser.getAttributeValue(null,"String_Node_Str");
      if (id == null || id == "String_Node_Str") {
        throw new InvalidStructureException("String_Node_Str",this.parser);
      }
      int quantity=this.parseInt(quantityString);
      s.setProductValue(id,quantity);
    }
    toWrite.addElement(s);
  }
 else   if (name.equals("String_Node_Str")) {
    String source=parser.getAttributeValue(null,"String_Node_Str");
    if (source == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    String destination=parser.getAttributeValue(null,"String_Node_Str");
    if (destination == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    Stock sourceStock=retrieve(source);
    if (sourceStock == null) {
      sourceStock=new Stock(source,new Hashtable<String,Integer>());
    }
    Stock destinationStock=retrieve(destination);
    if (destinationStock == null) {
      destinationStock=new Stock(source,new Hashtable<String,Integer>());
    }
    while (this.nextTagInBlock("String_Node_Str")) {
      this.checkNode("String_Node_Str");
      String productId=parser.getAttributeValue(null,"String_Node_Str");
      String quantityString=parser.getAttributeValue(null,"String_Node_Str");
      if (productId == null || productId == "String_Node_Str") {
        throw new InvalidStructureException("String_Node_Str",this.parser);
      }
      int quantity=this.parseInt(quantityString);
      sourceStock.setProductValue(productId,sourceStock.getProductValue(productId) - quantity);
      destinationStock.setProductValue(productId,destinationStock.getProductValue(productId) - quantity);
    }
    toWrite.addElement(sourceStock);
    toWrite.addElement(destinationStock);
  }
  Stock[] tw=new Stock[toWrite.size()];
  int i=0;
  for (  Stock s : toWrite) {
    tw[i]=s;
    i++;
  }
  commit(tw);
  return null;
}

Fixed version (ground truth):
public Stock[] parse() throws InvalidStructureException, IOException, XmlPullParserException {
  this.checkNode(new String[]{"String_Node_Str","String_Node_Str"});
  String name=parser.getName().toLowerCase();
  Vector<Stock> toWrite=new Vector<Stock>();
  String dateModified=parser.getAttributeValue(null,"String_Node_Str");
  if (dateModified == null) {
    throw new InvalidStructureException("String_Node_Str" + name + "String_Node_Str",this.parser);
  }
  Date modified=DateUtils.parseDateTime(dateModified);
  if (name.equals("String_Node_Str")) {
    String entityId=parser.getAttributeValue(null,"String_Node_Str");
    if (entityId == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    Stock s=retrieve(entityId);
    if (s == null) {
      s=new Stock(entityId,new Hashtable<String,Integer>());
    }
    while (this.nextTagInBlock("String_Node_Str")) {
      this.checkNode("String_Node_Str");
      String id=parser.getAttributeValue(null,"String_Node_Str");
      String quantityString=parser.getAttributeValue(null,"String_Node_Str");
      if (id == null || id == "String_Node_Str") {
        throw new InvalidStructureException("String_Node_Str",this.parser);
      }
      int quantity=this.parseInt(quantityString);
      s.setProductValue(id,quantity);
    }
    toWrite.addElement(s);
  }
 else   if (name.equals("String_Node_Str")) {
    String source=parser.getAttributeValue(null,"String_Node_Str");
    if (source == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    String destination=parser.getAttributeValue(null,"String_Node_Str");
    if (destination == null) {
      throw new InvalidStructureException("String_Node_Str",this.parser);
    }
    Stock sourceStock=retrieve(source);
    if (sourceStock == null) {
      sourceStock=new Stock(source,new Hashtable<String,Integer>());
    }
    Stock destinationStock=retrieve(destination);
    if (destinationStock == null) {
      destinationStock=new Stock(destination,new Hashtable<String,Integer>());
    }
    while (this.nextTagInBlock("String_Node_Str")) {
      this.checkNode("String_Node_Str");
      String productId=parser.getAttributeValue(null,"String_Node_Str");
      String quantityString=parser.getAttributeValue(null,"String_Node_Str");
      if (productId == null || productId == "String_Node_Str") {
        throw new InvalidStructureException("String_Node_Str",this.parser);
      }
      int quantity=this.parseInt(quantityString);
      sourceStock.setProductValue(productId,sourceStock.getProductValue(productId) - quantity);
      destinationStock.setProductValue(productId,destinationStock.getProductValue(productId) + quantity);
    }
    toWrite.addElement(sourceStock);
    toWrite.addElement(destinationStock);
  }
  Stock[] tw=new Stock[toWrite.size()];
  int i=0;
  for (  Stock s : toWrite) {
    tw[i]=s;
    i++;
  }
  commit(tw);
  return tw;
}