286N/A * reserved comment block 286N/A * DO NOT REMOVE OR ALTER! 286N/A * Copyright 1999-2004 The Apache Software Foundation. 286N/A * Licensed under the Apache License, Version 2.0 (the "License"); 286N/A * you may not use this file except in compliance with the License. 286N/A * You may obtain a copy of the License at 286N/A * Unless required by applicable law or agreed to in writing, software 286N/A * distributed under the License is distributed on an "AS IS" BASIS, 286N/A * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 286N/A * See the License for the specific language governing permissions and 286N/A * limitations under the License. 286N/A * Base class for functions that accept one argument that can be defaulted if 286N/A * Execute the first argument expression that is expected to return a 286N/A * nodeset. If the argument is null, then return the current context node. 286N/A * @param xctxt Runtime XPath context. 286N/A * @return The first node of the executed nodeset, or the current context 286N/A * node if the first argument is null. 286N/A * @throws javax.xml.transform.TransformerException if an error occurs while 286N/A * executing the argument expression. 286N/A * Tell if the expression is a nodeset expression. 286N/A * @return true if the expression can be represented as a nodeset. 286N/A * Execute the first argument expression that is expected to return a 286N/A * string. If the argument is null, then get the string value from the 286N/A * current context node. 286N/A * @param xctxt Runtime XPath context. 286N/A * @return The string value of the first argument, or the string value of the 286N/A * current context node if the first argument is null. 286N/A * @throws javax.xml.transform.TransformerException if an error occurs while 286N/A * executing the argument expression. 286N/A * Execute the first argument expression that is expected to return a 286N/A * number. If the argument is null, then get the number value from the 286N/A * current context node. 286N/A * @param xctxt Runtime XPath context. 286N/A * @return The number value of the first argument, or the number value of the 286N/A * current context node if the first argument is null. 286N/A * @throws javax.xml.transform.TransformerException if an error occurs while 286N/A * executing the argument expression. 286N/A * Check that the number of arguments passed to this function is correct. 286N/A * @param argNum The number of arguments that is being passed to the function. 286N/A * @throws WrongNumberArgsException if the number of arguments is not 0 or 1. 286N/A * Constructs and throws a WrongNumberArgException with the appropriate 286N/A * message for this function object. 286N/A * @throws WrongNumberArgsException 286N/A * Tell if this expression or it's subexpressions can traverse outside 286N/A * @return true if traversal outside the context node's subtree can occur.