1 /* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 4 */ 5 /* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22 package com.sun.org.apache.xalan.internal.extensions; 23 24 import javax.xml.transform.ErrorListener; 25 26 import com.sun.org.apache.xpath.internal.objects.XObject; 27 import org.w3c.dom.Node; 28 import org.w3c.dom.traversal.NodeIterator; 29 30 /** 31 * An object that implements this interface can supply 32 * information about the current XPath expression context. 33 */ 34 public interface ExpressionContext 35 { 36 37 /** 38 * Get the current context node. 39 * @return The current context node. 40 */ getContextNode()41 public Node getContextNode(); 42 43 /** 44 * Get the current context node list. 45 * @return An iterator for the current context list, as 46 * defined in XSLT. 47 */ getContextNodes()48 public NodeIterator getContextNodes(); 49 50 /** 51 * Get the error listener. 52 * @return The registered error listener. 53 */ getErrorListener()54 public ErrorListener getErrorListener(); 55 56 /** 57 * Get the value of a node as a number. 58 * @param n Node to be converted to a number. May be null. 59 * @return value of n as a number. 60 */ toNumber(Node n)61 public double toNumber(Node n); 62 63 /** 64 * Get the value of a node as a string. 65 * @param n Node to be converted to a string. May be null. 66 * @return value of n as a string, or an empty string if n is null. 67 */ toString(Node n)68 public String toString(Node n); 69 70 /** 71 * Get a variable based on it's qualified name. 72 * 73 * @param qname The qualified name of the variable. 74 * 75 * @return The evaluated value of the variable. 76 * 77 * @throws javax.xml.transform.TransformerException 78 */ getVariableOrParam(com.sun.org.apache.xml.internal.utils.QName qname)79 public XObject getVariableOrParam(com.sun.org.apache.xml.internal.utils.QName qname) 80 throws javax.xml.transform.TransformerException; 81 82 /** 83 * Get the XPathContext that owns this ExpressionContext. 84 * 85 * Note: exslt:function requires the XPathContext to access 86 * the variable stack and TransformerImpl. 87 * 88 * @return The current XPathContext. 89 * @throws javax.xml.transform.TransformerException 90 */ getXPathContext()91 public com.sun.org.apache.xpath.internal.XPathContext getXPathContext() 92 throws javax.xml.transform.TransformerException; 93 94 } 95