/* * reserved comment block * DO NOT REMOVE OR ALTER! */ /* * Copyright 1999-2004 The Apache Software Foundation. * * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * $Id: ExpressionContext.java,v 1.2.4.1 2005/09/10 19:34:03 jeffsuttor Exp $ */ package com.sun.org.apache.xalan.internal.extensions; import javax.xml.transform.ErrorListener; import com.sun.org.apache.xpath.internal.objects.XObject; import org.w3c.dom.Node; import org.w3c.dom.traversal.NodeIterator; /** * An object that implements this interface can supply * information about the current XPath expression context. */ public interface ExpressionContext { /** * Get the current context node. * @return The current context node. */ public Node getContextNode(); /** * Get the current context node list. * @return An iterator for the current context list, as * defined in XSLT. */ public NodeIterator getContextNodes(); /** * Get the error listener. * @return The registered error listener. */ public ErrorListener getErrorListener(); /** * Get the value of a node as a number. * @param n Node to be converted to a number. May be null. * @return value of n as a number. */ public double toNumber(Node n); /** * Get the value of a node as a string. * @param n Node to be converted to a string. May be null. * @return value of n as a string, or an empty string if n is null. */ public String toString(Node n); /** * Get a variable based on it's qualified name. * * @param qname The qualified name of the variable. * * @return The evaluated value of the variable. * * @throws javax.xml.transform.TransformerException */ public XObject getVariableOrParam(com.sun.org.apache.xml.internal.utils.QName qname) throws javax.xml.transform.TransformerException; /** * Get the XPathContext that owns this ExpressionContext. * * Note: exslt:function requires the XPathContext to access * the variable stack and TransformerImpl. * * @return The current XPathContext. * @throws javax.xml.transform.TransformerException */ public com.sun.org.apache.xpath.internal.XPathContext getXPathContext() throws javax.xml.transform.TransformerException; }