| /* |
| * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//jxpath/src/java/org/apache/commons/jxpath/Function.java,v 1.3 2002/04/24 04:05:41 dmitri Exp $ |
| * $Revision: 1.3 $ |
| * $Date: 2002/04/24 04:05:41 $ |
| * |
| * ==================================================================== |
| * The Apache Software License, Version 1.1 |
| * |
| * |
| * Copyright (c) 1999-2001 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, if |
| * any, must include the following acknowlegement: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowlegement may appear in the software itself, |
| * if and wherever such third-party acknowlegements normally appear. |
| * |
| * 4. The names "The Jakarta Project", "Commons", and "Apache Software |
| * Foundation" must not be used to endorse or promote products derived |
| * from this software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache" |
| * nor may "Apache" appear in their names without prior written |
| * permission of the Apache Group. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation and was |
| * originally based on software copyright (c) 2001, Plotnix, Inc, |
| * <http://www.plotnix.com/>. |
| * For more information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| package org.apache.commons.jxpath; |
| |
| /** |
| * Extension function interface. Extension functions are grouped into |
| * {@link Functions Functions} objects, which are installed on |
| * JXPathContexts using the {@link JXPathContext#setFunctions JXPathContext.setFunctions()} |
| * call. |
| * <p> |
| * The Function interface can be implemented directly. However, |
| * most of the time JXPath's built-in implementations should suffice. |
| * See {@link ClassFunctions ClassFunctions} and {@link PackageFunctions PackageFunctions}. |
| * |
| * @author Dmitri Plotnikov |
| * @version $Revision: 1.3 $ $Date: 2002/04/24 04:05:41 $ |
| */ |
| public interface Function { |
| |
| /** |
| * Computes the value of the function. Each implementation of Function |
| * is responsible for conversion of supplied parameters to the required |
| * argument types. |
| * |
| * @param context can be used to acquire the context in which the |
| * function is being evaluted. |
| */ |
| Object invoke(ExpressionContext context, Object[] parameters); |
| } |