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 java.util.Set;
27 import net.jcip.annotations.Immutable;
28 import org.modeshape.common.util.CheckArg;
29 import org.modeshape.common.util.HashCode;
30
31 /**
32 * A dynamic operand that represents a (binary) arithmetic operation upon one or more other operands, used in {@link Comparison}
33 * and {@link Ordering} components.
34 */
35 @Immutable
36 public class ArithmeticOperand implements DynamicOperand {
37 private static final long serialVersionUID = 1L;
38
39 private final Set<SelectorName> selectorNames;
40 private final ArithmeticOperator operator;
41 private final DynamicOperand left;
42 private final DynamicOperand right;
43 private final int hc;
44
45 /**
46 * Create a arithmetic dynamic operand that operates upon the supplied operand(s).
47 *
48 * @param left the left-hand-side operand
49 * @param operator the arithmetic operator; may not be null
50 * @param right the right-hand-side operand
51 * @throws IllegalArgumentException if any of the arguments is null
52 */
53 public ArithmeticOperand( DynamicOperand left,
54 ArithmeticOperator operator,
55 DynamicOperand right ) {
56 CheckArg.isNotNull(operator, "operator");
57 this.selectorNames = SelectorName.nameSetFrom(left.selectorNames(), right.selectorNames());
58 this.operator = operator;
59 this.left = left;
60 this.right = right;
61 this.hc = HashCode.compute(left, operator, right);
62 }
63
64 /**
65 * {@inheritDoc}
66 *
67 * @see org.modeshape.graph.query.model.DynamicOperand#selectorNames()
68 */
69 public Set<SelectorName> selectorNames() {
70 return selectorNames;
71 }
72
73 /**
74 * Get the operator for this binary operand.
75 *
76 * @return the operator; never null
77 */
78 public ArithmeticOperator operator() {
79 return operator;
80 }
81
82 /**
83 * Get the left-hand operand.
84 *
85 * @return the left-hand operator; never null
86 */
87 public DynamicOperand left() {
88 return left;
89 }
90
91 /**
92 * Get the right-hand operand.
93 *
94 * @return the right-hand operator; never null
95 */
96 public DynamicOperand right() {
97 return right;
98 }
99
100 /**
101 * {@inheritDoc}
102 *
103 * @see java.lang.Object#toString()
104 */
105 @Override
106 public String toString() {
107 return Visitors.readable(this);
108 }
109
110 /**
111 * {@inheritDoc}
112 *
113 * @see java.lang.Object#hashCode()
114 */
115 @Override
116 public int hashCode() {
117 return hc;
118 }
119
120 /**
121 * {@inheritDoc}
122 *
123 * @see java.lang.Object#equals(java.lang.Object)
124 */
125 @Override
126 public boolean equals( Object obj ) {
127 if (obj == this) return true;
128 if (obj instanceof ArithmeticOperand) {
129 ArithmeticOperand that = (ArithmeticOperand)obj;
130 return this.operator() == that.operator() && this.left().equals(that.left()) && this.right().equals(that.right());
131 }
132 return false;
133 }
134
135 /**
136 * {@inheritDoc}
137 *
138 * @see org.modeshape.graph.query.model.Visitable#accept(org.modeshape.graph.query.model.Visitor)
139 */
140 public void accept( Visitor visitor ) {
141 visitor.visit(this);
142 }
143 }