RE: NullPointerException: appendChild()

[Jayaram Narayana]

hey john,

yes, i got the exact same thought as you did and tried the following
(fragment):

                        :
                        :
         Database database = (Database) c.newInstance();
         DatabaseManager.registerDatabase(database);
         col = DatabaseManager.getCollection("xmldb:xindice:///db/misc");
         XMLResource xmlResource = (XMLResource) col.getResource("test");
         Node node = xmlResource.getContentAsDOM();
         Document doc = node.getOwnerDocument();
         Element el = doc.createElement("newchild");
         node.appendChild((Node) el);
         NodeList nl = node.getChildNodes();

         for (int i = 0; i < nl.getLength(); i++)
                System.out.println("Node " + i + ": " + 
nl.item(i).getNodeName());

                        :
                        :

here's the output i get:

Node 0: parent
Node 1: newchild

which means we were right. however, when i retrieve the document thru the
console admin, i cannot see "newchild"

now what could be wrong? is there some commit i need to do on the database?

thanks,
-nani

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Wednesday, March 27, 2002 4:12 PM
To: [EMAIL PROTECTED]
Subject: RE: NullPointerException: appendChild()


Hi Nani,

I don't know if this is relevant, but cloneNode returns a copy with a parent
value of null. Since nodes added to other node structures need to have the
same parent, this might be your problem. Try using getOwnerDocument() to get
the parent, then create a new element to append.

John

> -----Original Message-----
> From: Jayaram Narayana [mailto:[EMAIL PROTECTED]
> Sent: mercredi, 27. mars 2002 11:11
> To: 'Xindice Dev. Group'
> Subject: NullPointerException: appendChild()
>
>
> hi!
>
> when i try to run this code against the xml given below i get
> the following
> exception:
>
> Has Children: true
> Exception in thread "main" java.lang.NullPointerException
> at
> org.apache.xindice.xml.dom.ContainerNodeImpl.appendChild(Unkno
> wn Source)
>
> the code fragment is:
>               :
>               :
>          Database database = (Database) c.newInstance();
>          DatabaseManager.registerDatabase(database);
>          col =
> DatabaseManager.getCollection("xmldb:xindice:///db/misc");
>          XMLResource xmlResource = (XMLResource)
> col.getResource("test");
>          Node node = xmlResource.getContentAsDOM();
>          System.out.println("Has Children: " + node.hasChildNodes());
>          Node newNode = node.cloneNode(true);
>          node.appendChild(newNode);
>               :
>               :
>
> the xml file is:
>
> <?xml version="1.0"?>
> <parent>
>       <child id="123">Text goes here</child>
> </parent>
>
> i am not able to figure out what i am doing wrong. any help
> will be greatly
> appreciated.
>
> thanks in advance,
> -nani
>
>