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package com.sun.org.apache.xerces.internal.dom;

import org.w3c.dom.DOMException;
import org.w3c.dom.Node;
import org.w3c.dom.traversal.NodeFilter;
import org.w3c.dom.traversal.TreeWalker;

This class implements the TreeWalker interface.
@xerces.internal
/** This class implements the TreeWalker interface. * * @xerces.internal * */
public class TreeWalkerImpl implements TreeWalker { // // Data //
When TRUE, the children of entites references are returned in the iterator.
/** When TRUE, the children of entites references are returned in the iterator. */
private boolean fEntityReferenceExpansion = false;
The whatToShow mask.
/** The whatToShow mask. */
int fWhatToShow = NodeFilter.SHOW_ALL;
The NodeFilter reference.
/** The NodeFilter reference. */
NodeFilter fNodeFilter;
The current Node.
/** The current Node. */
Node fCurrentNode;
The root Node.
/** The root Node. */
Node fRoot; // // Implementation Note: No state is kept except the data above // (fWhatToShow, fNodeFilter, fCurrentNode, fRoot) such that // setters could be created for these data values and the // implementation will still work. // // Constructor //
Public constructor
/** Public constructor */
public TreeWalkerImpl(Node root, int whatToShow, NodeFilter nodeFilter, boolean entityReferenceExpansion) { fCurrentNode = root; fRoot = root; fWhatToShow = whatToShow; fNodeFilter = nodeFilter; fEntityReferenceExpansion = entityReferenceExpansion; } public Node getRoot() { return fRoot; }
Return the whatToShow value
/** Return the whatToShow value */
public int getWhatToShow() { return fWhatToShow; } public void setWhatShow(int whatToShow){ fWhatToShow = whatToShow; }
Return the NodeFilter
/** Return the NodeFilter */
public NodeFilter getFilter() { return fNodeFilter; }
Return whether children entity references are included in the iterator.
/** Return whether children entity references are included in the iterator. */
public boolean getExpandEntityReferences() { return fEntityReferenceExpansion; }
Return the current Node.
/** Return the current Node. */
public Node getCurrentNode() { return fCurrentNode; }
Return the current Node.
/** Return the current Node. */
public void setCurrentNode(Node node) { if (node == null) { String msg = DOMMessageFormatter.formatMessage(DOMMessageFormatter.DOM_DOMAIN, "NOT_SUPPORTED_ERR", null); throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg); } fCurrentNode = node; }
Return the parent Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the parent Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node parentNode() { if (fCurrentNode == null) return null; Node node = getParentNode(fCurrentNode); if (node !=null) { fCurrentNode = node; } return node; }
Return the first child Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the first child Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node firstChild() { if (fCurrentNode == null) return null; Node node = getFirstChild(fCurrentNode); if (node !=null) { fCurrentNode = node; } return node; }
Return the last child Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the last child Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node lastChild() { if (fCurrentNode == null) return null; Node node = getLastChild(fCurrentNode); if (node !=null) { fCurrentNode = node; } return node; }
Return the previous sibling Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the previous sibling Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node previousSibling() { if (fCurrentNode == null) return null; Node node = getPreviousSibling(fCurrentNode); if (node !=null) { fCurrentNode = node; } return node; }
Return the next sibling Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the next sibling Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node nextSibling(){ if (fCurrentNode == null) return null; Node node = getNextSibling(fCurrentNode); if (node !=null) { fCurrentNode = node; } return node; }
Return the previous Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the previous Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node previousNode() { Node result; if (fCurrentNode == null) return null; // get sibling result = getPreviousSibling(fCurrentNode); if (result == null) { result = getParentNode(fCurrentNode); if (result != null) { fCurrentNode = result; return fCurrentNode; } return null; } // get the lastChild of result. Node lastChild = getLastChild(result); Node prev = lastChild ; while (lastChild != null) { prev = lastChild ; lastChild = getLastChild(prev) ; } lastChild = prev ; // if there is a lastChild which passes filters return it. if (lastChild != null) { fCurrentNode = lastChild; return fCurrentNode; } // otherwise return the previous sibling. if (result != null) { fCurrentNode = result; return fCurrentNode; } // otherwise return null. return null; }
Return the next Node from the current node, after applying filter, whatToshow. If result is not null, set the current Node.
/** Return the next Node from the current node, * after applying filter, whatToshow. * If result is not null, set the current Node. */
public Node nextNode() { if (fCurrentNode == null) return null; Node result = getFirstChild(fCurrentNode); if (result != null) { fCurrentNode = result; return result; } result = getNextSibling(fCurrentNode); if (result != null) { fCurrentNode = result; return result; } // return parent's 1st sibling. Node parent = getParentNode(fCurrentNode); while (parent != null) { result = getNextSibling(parent); if (result != null) { fCurrentNode = result; return result; } else { parent = getParentNode(parent); } } // end , return null return null; }
Internal function. Return the parent Node, from the input node after applying filter, whatToshow. The current node is not consulted or set.
/** Internal function. * Return the parent Node, from the input node * after applying filter, whatToshow. * The current node is not consulted or set. */
Node getParentNode(Node node) { if (node == null || node == fRoot) return null; Node newNode = node.getParentNode(); if (newNode == null) return null; int accept = acceptNode(newNode); if (accept == NodeFilter.FILTER_ACCEPT) return newNode; else //if (accept == NodeFilter.SKIP_NODE) // and REJECT too. { return getParentNode(newNode); } }
Internal function. Return the nextSibling Node, from the input node after applying filter, whatToshow. The current node is not consulted or set.
/** Internal function. * Return the nextSibling Node, from the input node * after applying filter, whatToshow. * The current node is not consulted or set. */
Node getNextSibling(Node node) { return getNextSibling(node, fRoot); }
Internal function. Return the nextSibling Node, from the input node after applying filter, whatToshow. NEVER TRAVERSES ABOVE THE SPECIFIED ROOT NODE. The current node is not consulted or set.
/** Internal function. * Return the nextSibling Node, from the input node * after applying filter, whatToshow. * NEVER TRAVERSES ABOVE THE SPECIFIED ROOT NODE. * The current node is not consulted or set. */
Node getNextSibling(Node node, Node root) { if (node == null || node == root) return null; Node newNode = node.getNextSibling(); if (newNode == null) { newNode = node.getParentNode(); if (newNode == null || newNode == root) return null; int parentAccept = acceptNode(newNode); if (parentAccept==NodeFilter.FILTER_SKIP) { return getNextSibling(newNode, root); } return null; } int accept = acceptNode(newNode); if (accept == NodeFilter.FILTER_ACCEPT) return newNode; else if (accept == NodeFilter.FILTER_SKIP) { Node fChild = getFirstChild(newNode); if (fChild == null) { return getNextSibling(newNode, root); } return fChild; } else //if (accept == NodeFilter.REJECT_NODE) { return getNextSibling(newNode, root); } } // getNextSibling(Node node) {
Internal function. Return the previous sibling Node, from the input node after applying filter, whatToshow. The current node is not consulted or set.
/** Internal function. * Return the previous sibling Node, from the input node * after applying filter, whatToshow. * The current node is not consulted or set. */
Node getPreviousSibling(Node node) { return getPreviousSibling(node, fRoot); }
Internal function. Return the previousSibling Node, from the input node after applying filter, whatToshow. NEVER TRAVERSES ABOVE THE SPECIFIED ROOT NODE. The current node is not consulted or set.
/** Internal function. * Return the previousSibling Node, from the input node * after applying filter, whatToshow. * NEVER TRAVERSES ABOVE THE SPECIFIED ROOT NODE. * The current node is not consulted or set. */
Node getPreviousSibling(Node node, Node root) { if (node == null || node == root) return null; Node newNode = node.getPreviousSibling(); if (newNode == null) { newNode = node.getParentNode(); if (newNode == null || newNode == root) return null; int parentAccept = acceptNode(newNode); if (parentAccept==NodeFilter.FILTER_SKIP) { return getPreviousSibling(newNode, root); } return null; } int accept = acceptNode(newNode); if (accept == NodeFilter.FILTER_ACCEPT) return newNode; else if (accept == NodeFilter.FILTER_SKIP) { Node fChild = getLastChild(newNode); if (fChild == null) { return getPreviousSibling(newNode, root); } return fChild; } else //if (accept == NodeFilter.REJECT_NODE) { return getPreviousSibling(newNode, root); } } // getPreviousSibling(Node node) {
Internal function. Return the first child Node, from the input node after applying filter, whatToshow. The current node is not consulted or set.
/** Internal function. * Return the first child Node, from the input node * after applying filter, whatToshow. * The current node is not consulted or set. */
Node getFirstChild(Node node) { if (node == null) return null; if ( !fEntityReferenceExpansion && node.getNodeType() == Node.ENTITY_REFERENCE_NODE) return null; Node newNode = node.getFirstChild(); if (newNode == null) return null; int accept = acceptNode(newNode); if (accept == NodeFilter.FILTER_ACCEPT) return newNode; else if (accept == NodeFilter.FILTER_SKIP && newNode.hasChildNodes()) { Node fChild = getFirstChild(newNode); if (fChild == null) { return getNextSibling(newNode, node); } return fChild; } else //if (accept == NodeFilter.REJECT_NODE) { return getNextSibling(newNode, node); } }
Internal function. Return the last child Node, from the input node after applying filter, whatToshow. The current node is not consulted or set.
/** Internal function. * Return the last child Node, from the input node * after applying filter, whatToshow. * The current node is not consulted or set. */
Node getLastChild(Node node) { if (node == null) return null; if ( !fEntityReferenceExpansion && node.getNodeType() == Node.ENTITY_REFERENCE_NODE) return null; Node newNode = node.getLastChild(); if (newNode == null) return null; int accept = acceptNode(newNode); if (accept == NodeFilter.FILTER_ACCEPT) return newNode; else if (accept == NodeFilter.FILTER_SKIP && newNode.hasChildNodes()) { Node lChild = getLastChild(newNode); if (lChild == null) { return getPreviousSibling(newNode, node); } return lChild; } else //if (accept == NodeFilter.REJECT_NODE) { return getPreviousSibling(newNode, node); } }
Internal function. The node whatToShow and the filter are combined into one result.
/** Internal function. * The node whatToShow and the filter are combined into one result. */
short acceptNode(Node node) { /*** 7.1.2.4. Filters and whatToShow flags Iterator and TreeWalker apply whatToShow flags before applying Filters. If a node is rejected by the active whatToShow flags, a Filter will not be called to evaluate that node. When a node is rejected by the active whatToShow flags, children of that node will still be considered, and Filters may be called to evaluate them. ***/ if (fNodeFilter == null) { if ( ( fWhatToShow & (1 << node.getNodeType()-1)) != 0) { return NodeFilter.FILTER_ACCEPT; } else { return NodeFilter.FILTER_SKIP; } } else { if ((fWhatToShow & (1 << node.getNodeType()-1)) != 0 ) { return fNodeFilter.acceptNode(node); } else { // What to show has failed. See above excerpt from spec. // Equivalent to FILTER_SKIP. return NodeFilter.FILTER_SKIP; } } } }