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 import org.modeshape.common.util.HashCode; 29 30 /** 31 * A constraint that evaluates to true when either of the other constraints evaluates to true. 32 */ 33 @Immutable 34 public class Or implements Constraint { 35 private static final long serialVersionUID = 1L; 36 37 private final Constraint left; 38 private final Constraint right; 39 private final int hc; 40 41 /** 42 * Create a constraint that evaluates to true if either of the two supplied constraints evaluates to true. 43 * 44 * @param left the left constraint 45 * @param right the right constraint 46 * @throws IllegalArgumentException if the left or right constraints are null 47 */ 48 public Or( Constraint left, 49 Constraint right ) { 50 CheckArg.isNotNull(left, "left"); 51 CheckArg.isNotNull(right, "right"); 52 this.left = left; 53 this.right = right; 54 this.hc = HashCode.compute(this.left, this.right); 55 } 56 57 /** 58 * Get the left-hand constraint. 59 * 60 * @return the left-hand constraint; never null 61 */ 62 public Constraint left() { 63 return left; 64 } 65 66 /** 67 * Get the right-hand constraint. 68 * 69 * @return the right-hand constraint; never null 70 */ 71 public Constraint right() { 72 return right; 73 } 74 75 /** 76 * {@inheritDoc} 77 * 78 * @see java.lang.Object#toString() 79 */ 80 @Override 81 public String toString() { 82 return Visitors.readable(this); 83 } 84 85 /** 86 * {@inheritDoc} 87 * 88 * @see java.lang.Object#hashCode() 89 */ 90 @Override 91 public int hashCode() { 92 return hc; 93 } 94 95 /** 96 * {@inheritDoc} 97 * 98 * @see java.lang.Object#equals(java.lang.Object) 99 */ 100 @Override 101 public boolean equals( Object obj ) { 102 if (obj == this) return true; 103 if (obj instanceof Or) { 104 Or that = (Or)obj; 105 if (this.hc != that.hc) return false; 106 return this.left.equals(that.left) && this.right.equals(that.right); 107 } 108 return false; 109 } 110 111 /** 112 * {@inheritDoc} 113 * 114 * @see org.modeshape.graph.query.model.Visitable#accept(org.modeshape.graph.query.model.Visitor) 115 */ 116 public void accept( Visitor visitor ) { 117 visitor.visit(this); 118 } 119 }