Weird thing in static string comparation

Question

I am parsing XML file with simple structure:
<?xml version='1.0' encoding='utf-8'?>
<list>
        <item>
                <ingredient id="1" count="1" />
                <production id="2" count="1" />
        </item>
</list>I have code block to parse <item> node:
     protected TableEntry parseEntry(Node n)
          TableEntry entry = new TableEntry();
          for(Node d = n.getFirstChild(); d != null; d = d.getNextSibling())
               if("ingredient".equalsIgnoreCase(d.getNodeName()))
                    // parse it
                    //entry.addIngredient
                    l2p.util.Log.add("loaded ingredient " + id + " count " + count);
               else if("production".equalsIgnoreCase(d.getNodeName()))
                    // parse it
                    //entry.addProduct
                    l2p.util.Log.add("loaded production " + id + " count " + count);
          if(entry.getIngredients().isEmpty() || entry.getProduction().isEmpty())
               Log.add("wrong node");
               for(Node d = n.getFirstChild(); d != null; d = d.getNextSibling())
                    Log.add(d.getNodeName());
               return null;
          return entry;
     }First block always works fine, but second not:
loading new entry
loaded ingridient 1 count 1
wrong node
#text
ingredient
#text
production
#textHow can it be? Looks like
"production".equalsIgnoreCase(d.getNodeName())
return false, while d.getNodeName() actually equals "production"
The most strange:
Only "production" can broke, never "ingredient".
About 1/3 of all parsed works fine, but after method become "broken" and skips "production" in all parsed nodes.
This bug appears only on production server, and never at developers workstation.
Server:
Linux server 2.6.28-17-server #58-Ubuntu SMP Tue Dec 1 22:13:36 UTC 2009 x86_64 GNU/Linux
java version "1.6.0_16"
Java(TM) SE Runtime Environment (build 1.6.0_16-b01)
Java HotSpot(TM) 64-Bit Server VM (build 14.2-b01, mixed mode)
Dev:
Win7 Ult
java version "1.6.0_17"
Java(TM) SE Runtime Environment (build 1.6.0_17-b04)
Java HotSpot(TM) 64-Bit Server VM (build 14.3-b01, mixed mode)

Answer 1

Oblitus wrote:
Which assumptions? I don't know. Like I said: I don't understand what you're trying to say, and I can't be bothered to read your code.
However, I 100% guarantee that you are making some assumptions. Assumptions about how Java works. Assumptions about what your code means to Java. Assumptions about which conditions will be true or not. Assumptions about which variables get assigned which values and when. Assumptions about how your mental idea of your algorithm and you code implemenation of that idea map to each other. And I also guarantee you that at least one of those assumptions is wrong.
So you can choose to believe me, accept that Java is behaving exactly as it's supposed to, or you can assume that the problem is with Java, file a bug report, and find a workaround.
I comparing
"production".equalsIgnoreCase(d.getNodeName()) when d.getNodeName() equals "production" and it returns false!You're assuming that's what's happening. I am highly confident that that assumption is wrong, and that's not really what's happening.
The only way you'll solve your problem is if you ask yourself, "What am *I* doing wrong?" and accept that it could be anything, even the things you're 100% sure you're doing right. (Actually, especially those things.)