package net.sf.saxon.expr;
import net.sf.saxon.trace.ExpressionPresenter;
import net.sf.saxon.om.Item;
import net.sf.saxon.om.NodeInfo;
import net.sf.saxon.om.Axis;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.pattern.AnyNodeTest;
/**
* Class ParentNodeExpression represents the XPath expression ".." or "parent::node()"
*/
public class ParentNodeExpression extends SingleNodeExpression {
/**
* Customize the error message on type checking
*/
protected String noContextMessage() {
return "Cannot select the parent of the context node";
}
/**
* Return the node selected by this SingleNodeExpression
* @param context The context for the evaluation
* @return the parent of the current node defined by the context
*/
public NodeInfo getNode(XPathContext context) throws XPathException {
Item item = context.getContextItem();
if (item==null) {
dynamicError("The context item is not set", "XPDY0002", context);
}
if (item instanceof NodeInfo) {
return ((NodeInfo)item).getParent();
} else {
dynamicError("The context item for the parent axis (..) is not a node", "XPTY0020", context);
return null;
}
}
/**
* Copy an expression. This makes a deep copy.
*
* @return the copy of the original expression
*/
public Expression copy() {
return new ParentNodeExpression();
}
/**
* Add a representation of this expression to a PathMap. The PathMap captures a map of the nodes visited
* by an expression in a source tree.
*
* @param pathMap the PathMap to which the expression should be added
* @param pathMapNodeSet
* @return the pathMapNode representing the focus established by this expression, in the case where this
* expression is the first operand of a path expression or filter expression
*/
public PathMap.PathMapNodeSet addToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodeSet) {
AxisExpression parent = new AxisExpression(Axis.PARENT, AnyNodeTest.getInstance());
parent.setContainer(getContainer());
return parent.addToPathMap(pathMap, pathMapNodeSet);
}
/**
* Determine which aspects of the context the expression depends on. The result is
* a bitwise-or'ed value composed from constants such as XPathContext.VARIABLES and
* XPathContext.CURRENT_NODE
*/
/*
public int getDependencies() {
return StaticProperty.CONTEXT_ITEM;
}
*/
/**
* Is this expression the same as another expression?
*/
public boolean equals(Object other) {
return (other instanceof ParentNodeExpression);
}
/**
* get HashCode for comparing two expressions
*/
public int hashCode() {
return "ParentNodeExpression".hashCode();
}
/**
* The toString() method for an expression attempts to give a representation of the expression
* in an XPath-like form, but there is no guarantee that the syntax will actually be true XPath.
* In the case of XSLT instructions, the toString() method gives an abstracted view of the syntax
*/
public String toString() {
return "..";
}
/**
* Diagnostic print of expression structure. The abstract expression tree
* is written to the supplied output destination.
*/
public void explain(ExpressionPresenter destination) {
destination.startElement("parent");
destination.endElement();
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (the "License");
// you may not use this file except in compliance with the License. You may obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
//