1 /* 2 * ModeShape (http://www.modeshape.org) 3 * See the COPYRIGHT.txt file distributed with this work for information 4 * regarding copyright ownership. Some portions may be licensed 5 * to Red Hat, Inc. under one or more contributor license agreements. 6 * See the AUTHORS.txt file in the distribution for a full listing of 7 * individual contributors. 8 * 9 * ModeShape is free software. Unless otherwise indicated, all code in ModeShape 10 * is licensed to you under the terms of the GNU Lesser General Public License as 11 * published by the Free Software Foundation; either version 2.1 of 12 * the License, or (at your option) any later version. 13 * 14 * ModeShape is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with this software; if not, write to the Free 21 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 22 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 23 */ 24 package org.modeshape.graph.query.model; 25 26 import net.jcip.annotations.Immutable; 27 import org.modeshape.common.util.CheckArg; 28 29 /** 30 * A specification of the ordering for the results. 31 */ 32 @Immutable 33 public class Ordering implements LanguageObject { 34 private static final long serialVersionUID = 1L; 35 36 private final DynamicOperand operand; 37 private final Order order; 38 39 /** 40 * Create a new ordering specification, given the supplied operand and order. 41 * 42 * @param operand the operand being ordered 43 * @param order the order type 44 * @throws IllegalArgumentException if the operand or order type is null 45 */ 46 public Ordering( DynamicOperand operand, 47 Order order ) { 48 CheckArg.isNotNull(operand, "operand"); 49 CheckArg.isNotNull(order, "order"); 50 this.operand = operand; 51 this.order = order; 52 } 53 54 /** 55 * Get the operand being ordered. 56 * 57 * @return the operand; never null 58 */ 59 public DynamicOperand operand() { 60 return operand; 61 } 62 63 /** 64 * The order type. 65 * 66 * @return the type; never null 67 */ 68 public Order order() { 69 return order; 70 } 71 72 /** 73 * {@inheritDoc} 74 * 75 * @see java.lang.Object#toString() 76 */ 77 @Override 78 public String toString() { 79 return Visitors.readable(this); 80 } 81 82 /** 83 * {@inheritDoc} 84 * 85 * @see java.lang.Object#hashCode() 86 */ 87 @Override 88 public int hashCode() { 89 return operand.hashCode(); 90 } 91 92 /** 93 * {@inheritDoc} 94 * 95 * @see java.lang.Object#equals(java.lang.Object) 96 */ 97 @Override 98 public boolean equals( Object obj ) { 99 if (obj == this) return true; 100 if (obj instanceof Ordering) { 101 Ordering that = (Ordering)obj; 102 if (this.order != that.order) return false; 103 return this.operand.equals(that.operand); 104 } 105 return false; 106 } 107 108 /** 109 * {@inheritDoc} 110 * 111 * @see org.modeshape.graph.query.model.Visitable#accept(org.modeshape.graph.query.model.Visitor) 112 */ 113 public void accept( Visitor visitor ) { 114 visitor.visit(this); 115 } 116 }