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DTMNodeList.javaAPI DocJava SE 5 API4294Fri Aug 26 14:56:00 BST 2005com.sun.org.apache.xml.internal.dtm.ref

DTMNodeList

public class DTMNodeList extends DTMNodeListBase
DTMNodeList gives us an implementation of the DOM's NodeList interface wrapped around a DTM Iterator. The author considers this something of an abominations, since NodeList was not intended to be a general purpose "list of nodes" API and is generally considered by the DOM WG to have be a mistake... but I'm told that some of the XPath/XSLT folks say they must have this solution. Please note that this is not necessarily equivlaent to a DOM NodeList operating over the same document. In particular:
  • If there are several Text nodes in logical succession (ie, across CDATASection and EntityReference boundaries), we will return only the first; the caller is responsible for stepping through them. (%REVIEW% Provide a convenience routine here to assist, pending proposed DOM Level 3 getAdjacentText() operation?)
  • Since the whole XPath/XSLT architecture assumes that the source document is not altered while we're working with it, we do not promise to implement the DOM NodeList's "live view" response to document mutation.

State: In progress!!

Fields Summary
private DTMIterator
m_iter
Constructors Summary
private DTMNodeList()
public DTMNodeList(DTMIterator dtmIterator)
Public constructor: Wrap a DTMNodeList around an existing and preconfigured DTMIterator WARNING: THIS HAS THE SIDE EFFECT OF ISSUING setShouldCacheNodes(true) AGAINST THE DTMIterator.

        if (dtmIterator != null) {
            int pos = dtmIterator.getCurrentPos();
            try {
                m_iter=(DTMIterator)dtmIterator.cloneWithReset();
            } catch(CloneNotSupportedException cnse) {
                m_iter = dtmIterator;
            }
            m_iter.setShouldCacheNodes(true);
            m_iter.runTo(-1);
            m_iter.setCurrentPos(pos);
        }
Methods Summary
public com.sun.org.apache.xml.internal.dtm.DTMIteratorgetDTMIterator()
Access the wrapped DTMIterator. I'm not sure whether anyone will need this or not, but let's write it and think about it.

        return m_iter;
public intgetLength()
The number of nodes in the list. The range of valid child node indices is 0 to length-1 inclusive.

        return (m_iter != null) ? m_iter.getLength() : 0;
public org.w3c.dom.Nodeitem(int index)
Returns the indexth item in the collection. If index is greater than or equal to the number of nodes in the list, this returns null.

param
indexIndex into the collection.
return
The node at the indexth position in the NodeList, or null if that is not a valid index.

        if (m_iter != null) {
            int handle=m_iter.item(index);
            if (handle == DTM.NULL) {
                return null;
            }
            return m_iter.getDTM(handle).getNode(handle);
        } else {
            return null;
        }