1 /* 2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/expr/DefaultTruthExpr.java,v 1.10 2006/02/05 21:47:40 elharo Exp $ 3 * $Revision: 1.10 $ 4 * $Date: 2006/02/05 21:47:40 $ 5 * 6 * ==================================================================== 7 * 8 * Copyright 2000-2002 bob mcwhirter & James Strachan. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions are 13 * met: 14 * 15 * * Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 18 * * Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * * Neither the name of the Jaxen Project nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 27 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 29 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 30 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 31 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 32 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 33 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 34 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 35 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 36 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 37 * 38 * ==================================================================== 39 * This software consists of voluntary contributions made by many 40 * individuals on behalf of the Jaxen Project and was originally 41 * created by bob mcwhirter <bob@werken.com> and 42 * James Strachan <jstrachan@apache.org>. For more information on the 43 * Jaxen Project, please see <http://www.jaxen.org/>. 44 * 45 * $Id: DefaultTruthExpr.java,v 1.10 2006/02/05 21:47:40 elharo Exp $ 46 */ 47 48 49 50 package org.jaxen.expr; 51 52 import java.util.List; 53 54 abstract class DefaultTruthExpr extends DefaultBinaryExpr 55 { 56 DefaultTruthExpr(Expr lhs, 57 Expr rhs) 58 { 59 super( lhs, 60 rhs ); 61 } 62 63 public String toString() 64 { 65 return "[(DefaultTruthExpr): " + getLHS() + ", " + getRHS() + "]"; 66 } 67 68 protected boolean bothAreSets(Object lhs, 69 Object rhs) 70 { 71 return ( lhs instanceof List 72 && 73 rhs instanceof List ); 74 } 75 76 protected boolean eitherIsSet(Object lhs, 77 Object rhs) 78 { 79 return ( lhs instanceof List 80 || 81 rhs instanceof List ); 82 } 83 84 protected boolean isSet(Object obj) 85 { 86 return ( obj instanceof List ); 87 } 88 89 protected boolean setIsEmpty( List set ) 90 { 91 return (set == null || set.size() == 0); 92 } 93 94 protected boolean eitherIsBoolean(Object lhs, 95 Object rhs) 96 { 97 return ( lhs instanceof Boolean 98 || 99 rhs instanceof Boolean ); 100 } 101 102 protected boolean bothAreBoolean(Object lhs, 103 Object rhs) 104 { 105 return ( lhs instanceof Boolean 106 && 107 rhs instanceof Boolean ); 108 } 109 110 protected boolean eitherIsNumber(Object lhs, 111 Object rhs) 112 { 113 return ( lhs instanceof Number 114 || 115 rhs instanceof Number ); 116 } 117 118 } 119