1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 // $Id: XPathFunction.java 446598 2006-09-15 12:55:40Z jeremias $ 18 19 package javax.xml.xpath; 20 21 import java.util.List; 22 23 /** 24 * <p><code>XPathFunction</code> provides access to XPath functions.</p> 25 * 26 * <p>Functions are identified by QName and arity in XPath.</p> 27 * 28 * @author <a href="mailto:Norman.Walsh (at) Sun.com">Norman Walsh</a> 29 * @author <a href="mailto:Jeff.Suttor (at) Sun.com">Jeff Suttor</a> 30 * @version $Revision: 446598 $, $Date: 2006-09-15 05:55:40 -0700 (Fri, 15 Sep 2006) $ 31 * @since 1.5 32 */ 33 public interface XPathFunction { 34 /** 35 * <p>Evaluate the function with the specified arguments.</p> 36 * 37 * <p>To the greatest extent possible, side-effects should be avoided in the 38 * definition of extension functions. The implementation evaluating an 39 * XPath expression is under no obligation to call extension functions in 40 * any particular order or any particular number of times.</p> 41 * 42 * @param args The arguments, <code>null</code> is a valid value. 43 * 44 * @return The result of evaluating the <code>XPath</code> function as an <code>Object</code>. 45 * 46 * @throws XPathFunctionException If <code>args</code> cannot be evaluated with this <code>XPath</code> function. 47 */ 48 public Object evaluate(List args) 49 throws XPathFunctionException; 50 } 51 52
