1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the "License"); 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 /* 19 * $Id: Neg.java 468655 2006-10-28 07:12:06Z minchau $ 20 */ 21 package org.apache.xpath.operations; 22 23 import org.apache.xpath.XPathContext; 24 import org.apache.xpath.objects.XNumber; 25 import org.apache.xpath.objects.XObject; 26 27 /** 28 * The unary '-' operation expression executer. 29 */ 30 public class Neg extends UnaryOperation 31 { 32 static final long serialVersionUID = -6280607702375702291L; 33 34 /** 35 * Apply the operation to two operands, and return the result. 36 * 37 * 38 * @param right non-null reference to the evaluated right operand. 39 * 40 * @return non-null reference to the XObject that represents the result of the operation. 41 * 42 * @throws javax.xml.transform.TransformerException 43 */ operate(XObject right)44 public XObject operate(XObject right) throws javax.xml.transform.TransformerException 45 { 46 return new XNumber(-right.num()); 47 } 48 49 /** 50 * Evaluate this operation directly to a double. 51 * 52 * @param xctxt The runtime execution context. 53 * 54 * @return The result of the operation as a double. 55 * 56 * @throws javax.xml.transform.TransformerException 57 */ num(XPathContext xctxt)58 public double num(XPathContext xctxt) 59 throws javax.xml.transform.TransformerException 60 { 61 62 return -(m_right.num(xctxt)); 63 } 64 65 } 66